Available online on 15.09.2026 at http://jddtonline.info

Journal of Drug Delivery and Therapeutics

Open Access to Pharmaceutical and Medical Research

Copyright  © 2026 The   Author(s): This is an open-access article distributed under the terms of the CC BY-NC 4.0 which permits unrestricted use, distribution, and reproduction in any medium for non-commercial use provided the original author and source are credited

Open Access Full Text Article  Review Article

Formulation and Evaluation of Niosome-Based Isotretinoin Gel: A Comprehensive Review

Ruchi Gupta ¹, Niharika Sahu ², Rahul Dev ¹, Rupesh Sahu ³, Dharmendra Sahu ¹, Shiv Kumar Bhardwaj ³*

¹ Gracious College of Pharmacy, Village-Belbhata, Abhanpur, Raipur-493661, Chhattisgarh, India

² Columbia College of Pharmacy, Tekari, Near Vidhansabha Road, Raipur-493111, Chhattisgarh, India

³ Columbia Institute of Pharmacy, Tekari, Near Vidhansabha Road, Raipur-493111, Chhattisgarh, India

 

 

Highlights

• Niosomes enhance topical delivery and follicular targeting of isotretinoin. 
• Controlled drug release minimizes skin irritation and improves patient compliance. 
• Niosomal gel improves drug stability, skin retention, and therapeutic efficacy. 
• Surfactant composition and cholesterol concentration critically influence vesicle characteristics. 
• Niosomal gels represent a promising nanocarrier platform for advanced acne therapy. 

 

 

 

 

 

 

 

 

 

 

 

 

1. Introduction 

Acne vulgaris is a common chronic inflammatory skin disorder affecting adolescents and adults worldwide. It originates in the pilosebaceous unit and involves excess sebum production, follicular hyperkeratinization, Cutibacterium acnes colonization and inflammation.¹ Topical therapy is preferred for mild-to-moderate acne because it provides localized treatment with minimal systemic exposure. Isotretinoin, a vitamin A–derived retinoid, effectively reduces sebum production, abnormal keratinization, bacterial proliferation and inflammation.² However, conventional formulations are limited by poor solubility, chemical instability, inadequate skin penetration and local irritation. Niosomes, composed of non-ionic surfactants and cholesterol, offer improved drug stability, controlled release, skin penetration and follicular targeting.³ Incorporating isotretinoin-loaded niosomes into a gel further enhances spread-ability, residence time, skin retention and patient acceptability. Therefore, optimized isotretinoin-loaded niosomal gels represent a promising nanocarrier-based approach for safer and more effective topical acne management. ⁴

2. Skin anatomy and barrier function

The skin is the body’s largest organ and acts as a protective barrier. It consists of three main layers: epidermis, dermis and hypodermis. The stratum corneum is the major barrier to drug penetration. Topical drugs penetrate mainly through intercellular, transcellular, and follicular pathways. Niosomes can improve skin penetration, hydration and follicular drug deposition, thereby enhance local drug delivery and reduce systemic exposure.⁵ 

3. Pathophysiology of acne vulgaris

Acne vulgaris is a multifactorial inflammatory disorder of the pilosebaceous unit involving hormonal, microbial, immune and genetic factors. Its main pathogenic mechanisms are excess sebum production, follicular hyperkeratinization, Cutibacterium acnes colonization and inflammation, resulting in comedones, papules, pustules, nodules and possible scarring.⁶ 

3.1 Sebaceous hyperactivity

Androgenic hormones stimulate sebaceous gland enlargement and excessive sebum secretion. Increased production of triglycerides, wax esters, squalene and free fatty acids creates a lipid-rich environment favorable for bacterial colonization. Oxidation of sebum lipids further contributes to inflammatory responses.⁷

3.2 Follicular hyperkeratinization

Abnormal differentiation and proliferation of keratinocytes result in excessive accumulation of corneocytes within the follicular canal. This leads to obstruction of the pilosebaceous duct and formation of micro-comedones, which subsequently develop into open (blackheads) or closed (whiteheads) comedones.⁸

3.3 Colonization by cutibacterium acnes

Cutibacterium acnes is a Gram-positive anaerobic bacterium that naturally resides within sebaceous follicles. Under conditions of follicular obstruction and excessive sebum production, bacterial proliferation increases significantly.⁹ The organism produces lipases, proteases, hyaluronidases, porphyrins and various virulence factors that degrade sebum triglycerides into inflammatory free fatty acids, further aggravating follicular inflammation.¹⁰

3.4 Inflammatory cascade

TLR activation triggers NF-κB and MAPK pathways, leading to the release of inflammatory mediators such as IL-1β, IL-6, IL-8, IL-17, and TNF-α. Persistent inflammation promotes acne progression and scarring. Oxidative stress, inflammasome activation and microbiome changes also contribute to acne pathogenesis, supporting the development of targeted anti-inflammatory and nanocarrier-based therapies. ¹¹

 

 

Table 1. Major pathogenic factors in acne vulgaris

Pathogenic factor	Mechanism	Clinical outcome	Therapeutic target	Ref
Excess sebum production	Androgen-mediated sebaceous gland activation	Oily skin	Retinoids, Antiandrogens	12
Follicular hyperkeratinization	Keratinocyte proliferation	Comedone formation	Isotretinoin	13
C. acnes colonization	Lipase production and biofilm formation	Inflammation	Antimicrobial agents	14
Cytokine release	IL-1β, IL-6, IL-8, TNF-α	Papules and pustules	Anti-inflammatory drugs	15
Oxidative stress	ROS generation	Tissue damage	Antioxidants	16
Immune dysregulation	Innate immune activation	Chronic inflammation	Targeted immunomodulation	17

 

 

4. Isotretinoin: Pharmacology and therapeutic significance

Isotretinoin is a vitamin A–derived retinoid and a highly effective treatment for moderate-to-severe acne. It reduces sebum production, follicular hyperkeratinization, C. acnes colonization, and inflammation. However, conventional topical isotretinoin is limited by poor solubility, instability, low skin penetration and irritation. Niosomal gels can improve isotretinoin stability, skin penetration, follicular targeting, sustained release and reduce irritation. Acne develops mainly through excess sebum, follicular hyperkeratinization, C. acnes colonization and inflammation.¹⁸

5. Niosomes: An advanced vesicular drug delivery system

5.1 Introduction to niosomes

Niosomes are vesicular drug carriers composed of non-ionic surfactants that can encapsulate both hydrophilic and lipophilic drugs. They offer good stability, biocompatibility, low toxicity, high drug-loading capacity and prolonged drug release. For topical delivery, niosomes enhance skin penetration, hydration, drug retention and follicular targeting. In isotretinoin therapy, they can improve drug stability and localized delivery while reducing irritation and systemic exposure, making them promising for acne management.¹⁹

5.2 Classification of Niosomes

Niosomes are classified based on vesicle size, lamellarity and method of preparation.

A. Based on lamellarity

Unilamellar vesicles (ULVs)

These vesicles possess a single phospholipid-like bilayer surrounding an aqueous core. They generally exhibit diameters ranging from 50 to 250 nm and provide efficient topical permeation due to their small size.²⁰

Multilamellar vesicles (MLVs)

Multilamellar vesicles consist of several concentric bilayers resembling an onion-like structure. These vesicles demonstrate higher drug loading capacity and prolonged drug release but generally possess larger particle sizes.²¹

Large unilamellar vesicles (LUVs)

LUVs contain a single bilayer with a relatively larger internal aqueous compartment, making them suitable for encapsulating hydrophilic drugs.²²

B. Based on size

Table 2. Based on size²³

Type	Particle Size
Small unilamellar vesicles	20–100 nm
Large unilamellar vesicles	100–1000 nm
Multilamellar vesicles	0.5–10 µm

 

5.3 Composition of niosomes

The pharmaceutical performance of niosomes is largely determined by their composition. Each component contributes to vesicle formation, stability, drug encapsulation and release characteristics.

Non-ionic surfactants

Non-ionic surfactants are essential for niosome bilayer formation. Commonly used surfactants include Span 20, Span 40, Span 60, Span 80, Tween 20, Tween 40, Tween 60, Tween 80, Brij 35, Brij 52 and Brij 72. Among these, Span 60 is preferred due to its high membrane rigidity, excellent drug entrapment and sustained drug release.²⁴

Cholesterol

Cholesterol acts as a membrane stabilizer by reducing bilayer permeability and preventing leakage of encapsulated drug. Appropriate cholesterol concentration increases vesicle rigidity, enhances physical stability, improves drug retention and prolongs storage life. Excessive cholesterol, however, may decrease drug entrapment by competing with drug molecules within the bilayer.²⁵

Charge Inducers

Charge-inducing agents prevent vesicle aggregation by generating electrostatic repulsion. Common examples include dicetyl phosphate (negative charge) and stearylamine (positive charge).²⁶

Hydration Medium

Hydration media such as phosphate buffer (pH 7.4), phosphate-buffered saline (PBS) and distilled water are used for niosome preparation and influence vesicle size, drug entrapment, and release behavior.²⁷

5.4 Mechanism of niosome formation

Niosomes are formed by the self-assembly of amphiphilic surfactants upon hydration, producing bilayer vesicles. Hydrophilic drugs are entrapped in the aqueous core, while lipophilic drugs (e.g., isotretinoin) are incorporated into the hydrophobic bilayer. Vesicle size can be reduced by sonication, extrusion, or high-pressure homogenization.²⁸ Figure 1 illustrates the structural organization of a niosomal vesicle, highlighting its amphiphilic bilayer architecture and the encapsulation of isotretinoin within the vesicular system.

 

 

                  Figure 1: Structure of a niosome

(Schematic representation of a niosomal vesicle showing the non-ionic surfactant bilayer, hydrophilic head groups, hydrophobic tails, aqueous core and localization of isotretinoin within the lipid bilayer).

 

 

5.5 Mechanism of skin penetration

Niosomes improve topical drug delivery through multiple complementary mechanisms.

Hydration Effect

Niosomal vesicles increase hydration of the stratum corneum, causing swelling of keratinocytes and loosening of lipid packing. This transient modification facilitates drug diffusion.²⁹

Lipid Interaction

Non-ionic surfactants interact with intercellular lipids, disrupting their highly ordered arrangement and reducing barrier resistance.³⁰

Vesicle Adsorption

Niosomes adsorb onto the skin surface and gradually release isotretinoin over an extended period, maintaining prolonged therapeutic concentrations.³¹

 

Follicular Targeting

Hair follicles and sebaceous glands serve as reservoirs for nanosized vesicles. Because acne originates in the pilosebaceous unit, follicular accumulation of isotretinoin-loaded niosomes significantly enhances localized therapy while minimizing unnecessary exposure of healthy skin.³²

Controlled Drug Release

Following penetration, isotretinoin diffuses gradually from the bilayer membrane, maintaining sustained therapeutic levels while reducing peak concentrations responsible for irritation.³³ Figures 2 and 3 illustrate the mechanism of topical delivery and therapeutic action of isotretinoin-loaded niosomal gel, highlighting skin penetration, interaction with the stratum corneum, follicular targeting, controlled drug release and localized therapeutic effects. Figure 3 further provides a comprehensive overview of the niosomal structure and the sequential events involved in efficient topical drug delivery.

 

 

Figure 2: Mechanism of skin penetration and localized drug delivery of isotretinoin-loaded niosomal gel.

(Schematic illustration showing the deposition of isotretinoin-loaded niosomal gel on the skin surface, hydration of the stratum corneum, interaction with skin lipids, opening of intercellular pathways, follicular penetration, controlled drug release and localized therapeutic action.)

Figure 3: Biological mechanism of skin penetration and controlled release of isotretinoin-loaded niosomes.

(Comprehensive schematic illustrating the interaction of isotretinoin-loaded niosomes with the stratum corneum, enhancement of skin hydration, disruption of intercellular lipid domains, follicular targeting, sustained drug release, molecular organization of niosomes and localized therapeutic effects in acne vulgaris).

 

 

6. Advantages of niosomal drug delivery

Niosomal drug delivery systems provide numerous pharmaceutical and therapeutic advantages over conventional topical formulations. isotretinoin from photodegradation and oxidative degradation, improving formulation stability. Niosomes also reduce direct contact of free drug with the epidermis, thereby minimizing irritation, erythema, dryness and peeling commonly associated with topical retinoids. Additional benefits include high drug-loading efficiency, ease of preparation, cost-effective manufacturing, compatibility with various gel bases and the potential for scalable industrial production.^34–36

 

 

 

 

7. Formulation of isotretinoin-loaded niosomal gel

7.1 Formulation strategy

The successful formulation of isotretinoin-loaded niosomal gel requires the systematic selection of formulation components and optimization of processing parameters to achieve high drug entrapment efficiency, nanosized vesicles, controlled drug release and excellent physicochemical stability. Owing to its highly lipophilic and photosensitive nature, isotretinoin is encapsulated within the hydrophobic bilayer of niosomes, which protects the drug from chemical and photodegradation while enhancing its penetration and retention within the pilosebaceous unit. The formulation process generally involves two sequential stages: (i) preparation of isotretinoin-loaded niosomes and (ii) incorporation of the optimized niosomal dispersion into a suitable gel base. The resulting niosomal gel should exhibit appropriate viscosity, excellent spread ability, skin-compatible pH, uniform drug content, prolonged residence time and sustained drug release to ensure enhanced therapeutic efficacy, improved patient compliance and reduced local irritation.^37–39

7.2 Quality target product profile (QTPP)

The Quality Target Product Profile (QTPP) defines the desired characteristics of the finished topical product.

 

7.3 Critical material attributes (CMAs)

Critical Material Attributes (CMAs) are the physicochemical properties of raw materials that significantly influence the quality, stability and performance of isotretinoin-loaded niosomal gel formulations. Appropriate selection and optimization of these attributes are essential to achieve efficient vesicle formation, high drug entrapment efficiency, controlled drug release, and long-term formulation stability.⁴⁰ 

7.4 Critical process parameters (CPPs)

Critical Process Parameters (CPPs) are the manufacturing variables that significantly influence the quality, reproducibility and performance of isotretinoin-loaded niosomal formulations. Proper control and optimization of these parameters are essential to ensure consistent vesicle formation, uniform particle size distribution, high encapsulation efficiency and long-term physicochemical stability.⁴¹ 

7.5 Methods of niosome preparation

Several techniques have been employed for preparing isotretinoin-loaded niosomes. The selection of the preparation method influences particle size, entrapment efficiency, scalability, and stability.

A. Thin film hydration method⁴²

This is the most widely reported and preferred technique.

 

 

Procedure:

                 Dissolve isotretinoin, surfactant and cholesterol in chloroform: methanol.

 

Evaporate the solvent using a rotary evaporator under reduced pressure.

 

A thin lipid film forms on the flask wall.

 

Hydrate the film with phosphate buffer.

 

Sonicate or extrude to reduce vesicle size.

 

Collect isotretinoin-loaded niosomes.

 

Advantages:

• High encapsulation efficiency. 
• Uniform vesicle formation. 
• Suitable for lipophilic drugs. 
• Reproducible and scalable. 

 

 

 

B. Ether Injection Method⁴³

An organic solution containing surfactant and drug is injected slowly into a heated aqueous phase, producing unilamellar vesicles as the solvent evaporates.

 

Prepare organic phase (Dissolve isotretinoin and surfactant in an organic solvent).

 

Prepare aqueous phase (Heat the aqueous phase under continuous stirring).

 

Inject organic phase (Slowly inject the organic phase into the heated aqueous phase).

 

 Evaporate solvent (Allow the solvent to evaporate during stirring).

 

Form vesicles (Unilamellar niosomes are formed).

 

Cool and purify (Cool the dispersion and remove unentrapped drug/residual solvent).

 

C. Reverse phase evaporation method⁴⁴

A water-in-oil emulsion is prepared, followed by solvent evaporation to form large vesicles with high encapsulation efficiency.

Prepare organic phase (Dissolve surfactant and isotretinoin in an organic solvent).

 

  Form emulsion (Add the aqueous phase gradually to form a water-in-oil emulsion).

 

  Evaporate solvent (Remove the organic solvent under reduced pressure).

 

  Form vesicles (Large niosomes are formed with high drug entrapment).

 

  Purify and characterize (Remove unentrapped drug and evaluate the vesicles).

 

D. Micro-fluidization⁴⁵

High-pressure collision of fluid streams produces uniformly sized niosomes with narrow particle size distribution.

Prepare dispersion (Mix surfactant, cholesterol, drug and aqueous phase).

 

High-pressure processing (Pass the dispersion through a microfluidizer).

 

Reduce size (High-pressure fluid collision reduces vesicle size).

 

Collect niosomes (Obtain uniformly sized niosomes with narrow size distribution).

 

 

 

 

E. Bubble method⁴⁶

This solvent-free approach generates vesicles by bubbling inert gas through a surfactant solution at elevated temperature.

Prepare surfactant solution (Disperse surfactant and cholesterol in an aqueous medium).

 

Heat (Maintain the dispersion at an elevated temperature).

 

Bubble inert gas (Pass nitrogen or another inert gas through the solution).

 

Form vesicles (Gas bubbling promotes vesicle formation).

 

Cool and collect (Cool the dispersion to obtain niosomes).

 

7.6 Preparation of niosomal gel⁴⁷

The optimized niosomal dispersion is incorporated into a gel matrix to improve topical application and increase residence time on the skin.

Typical Procedure

Disperse Carbopol 934 in purified water.

 

Allow complete hydration for several hours.

 

Add glycerol and propylene glycol under continuous stirring.

 

Incorporate the optimized niosomal dispersion slowly.

 

Adjust pH using triethanolamine.

 

Mix until a homogeneous gel is obtained.

 

Store in airtight, light-resistant containers.

 

The resulting gel should be smooth, homogeneous, non-gritty and free from phase separation.

 

 

7.7 Optimization of formulation

Optimization is a crucial step in the development of isotretinoin-loaded niosomal gel, as it identifies the optimal combination of formulation variables required to achieve the desired product quality and therapeutic performance. A systematic optimization strategy, commonly employing Design of Experiments (DoE) or Response Surface Methodology (RSM), is used to evaluate the influence of formulation factors on the critical quality attributes of the final product.⁴⁸ 

 

 

 

 

 

 

 

Table 3. Independent and dependent variables used for optimization of isotretinoin-loaded niosomal gel

Category	Variables
Independent Variables (Factors)	Surfactant concentration
	Cholesterol concentration
	Hydration time
	Sonication time
Dependent Variables (Responses)	Particle size
	Polydispersity index (PDI)
	Entrapment efficiency (%)
	Zeta potential
	In vitro drug release (%)
	Viscosity (cP)

 

 

7.8 Quality by design (QbD) approach

Application of Quality by Design (QbD) facilitates a systematic understanding of the relationship between formulation variables and critical quality attributes. Using Design of Experiments (DoE), such as factorial or Box–Behnken designs, researchers can optimize surfactant-to-cholesterol ratio, hydration conditions and sonication parameters to achieve targeted particle size, high entrapment efficiency and sustained drug release with fewer experimental trials.⁴⁹ 

8. Characterization and evaluation of isotretinoin-loaded niosomes

Comprehensive characterization of isotretinoin-loaded niosomes is essential to ensure reproducibility, stability, drug-loading capacity and therapeutic performance. Physicochemical evaluation provides insight into vesicle morphology, particle size distribution, surface charge, encapsulation efficiency and drug release behavior all of which influence topical delivery and clinical efficacy.⁵⁰

8.1 Preformulation studies

Preformulation studies provide essential information regarding the physicochemical properties of isotretinoin and its compatibility with excipients used in the development of niosomal gel formulations. These investigations form the basis for rational formulation design by facilitating the selection of suitable surfactants, membrane stabilizers, solvents and gel-forming polymers to ensure optimal drug loading, stability and therapeutic performance.^51,52

 

 

Table 4. Major pre-formulation parameters evaluated for isotretinoin

Preformulation Parameter	Purpose	Ref
Organoleptic properties	Identification of drug characteristics (color, odor, appearance)	53
Solubility profile	Selection of suitable solvents and formulation components	54
Melting point	Assessment of purity and thermal characteristics	55
Partition coefficient (Log P)	Determination of lipophilicity and membrane permeability	56
pKa	Prediction of ionization behavior and formulation pH	57
UV absorption wavelength (λmax)	Quantitative drug estimation by UV spectrophotometry	58
Drug–excipient compatibility	Evaluation of potential physicochemical interactions	59
Stability under light and temperature	Assessment of chemical stability during formulation and storage	60

 

 

8.2 Particle size analysis

Particle size, measured by DLS, influences skin penetration, follicular targeting, drug release, and therapeutic efficacy. An optimized isotretinoin niosomal formulation generally shows a size of 100–300 nm for effective follicular localization and skin retention.⁶¹

 

 

8.3 Polydispersity index (PDI)

PDI, measured by DLS, indicates niosomal size uniformity. A PDI < 0.30 suggests a narrow, homogeneous distribution and good formulation stability.⁶²

Zeta potential measures the surface charge of niosomes and indicates colloidal stability by preventing vesicle aggregation, fusion and sedimentation. ⁶³

8.5 Entrapment efficiency

Entrapment efficiency (EE) measures the percentage of isotretinoin encapsulated in niosomes. Unentrapped drug is separated by ultracentrifugation, dialysis, or gel filtration and quantified by UV–Vis or HPLC.⁶⁴ 

Formula:⁶⁵

Entrapment Efficiency (EE%)    100

8.6 Drug content

Drug content analysis determines isotretinoin concentration and uniformity using UV–Vi’s spectrophotometry or HPLC, with an acceptable range of 95–105% of labeled content.⁶⁶

8.7 Morphological evaluation

Morphology influences vesicle stability, drug loading and release kinetics. Electron microscopy techniques are routinely employed for structural characterization.

Transmission electron microscopy (TEM)

TEM evaluates niosomal vesicle shape, bilayer structure, internal morphology and particle size for detailed morphological characterization.⁶⁷

Scanning electron microscopy (SEM)

SEM evaluates niosome morphology, surface characteristics and aggregation. Optimized formulations show spherical, smooth, discrete and uniformly distributed vesicles with minimal aggregation.⁶⁸

8.8 FTIR analysis

FTIR assesses drug–excipient compatibility by identifying functional groups and detecting potential chemical interactions or structural changes.⁶⁹ 

8.9 Differential scanning calorimetry (DSC)

DSC evaluates isotretinoin’s thermal behavior, crystallinity, phase transition and encapsulation by analyzing heat-flow changes after formulation.⁷⁰ 

8.10 X-Ray diffraction (XRD)

XRD determines the crystalline or amorphous state of isotretinoin by comparing the diffraction patterns of pure drug and niosomal formulations.⁷¹

9. Evaluation of isotretinoin niosomal gel

Following incorporation into the gel base, additional quality control parameters are evaluated.

 

9.1 Appearance

Appearance is a key quality attribute; the niosomal gel should be smooth, homogeneous, non-gritty, lump-free and uniformly colored, indicating physical stability.⁷²

9.2 pH

The formulation pH is measured using a calibrated digital pH meter. The optimized niosomal gel should have a skin-compatible pH of 5.5–6.8, minimizing irritation and maintaining drug stability.⁷³

9.3 Viscosity

Viscosity is measured using a Brookfield viscometer and should be optimized to ensure easy application, adequate skin retention, controlled drug release and good patient acceptability.⁷⁴

9.4 Spread-ability

Spread ability ensures easy, uniform application and drug distribution, improving patient compliance and therapeutic efficacy.⁷⁵

9.5 Extrudability

Extrudability assesses the ease of gel expulsion from tubes, ensuring convenient dispensing and patient usability.⁷⁶

9.6 Drug Content Uniformity

Drug content uniformity ensures homogeneous isotretinoin distribution, with an acceptable range of 95–105% for accurate dosing.⁷⁷

9.7 Homogeneity

Homogeneity is assessed visually to ensure uniform dispersion and absence of air bubbles, phase separation, precipitation, or aggregation.⁷⁸ 

10. In Vitro drug release studies

In vitro drug release studies evaluate the rate and extent of isotretinoin release, aiding formulation optimization and prediction of in vivo performance.⁷⁹

Table 5. Parameters evaluated during in vitro drug release⁸⁰

Parameter	Importance
Cumulative drug release (%)	Release profile
Release rate	Drug diffusion
Release duration	Sustained delivery
Diffusion coefficient	Permeation characteristics
Drug release kinetics	Mechanism of release

 

11. Drug release kinetic models

Mathematical modeling of release data provides insight into the mechanism of drug release from niosomal gel.

 

Table 6. Common drug release kinetic models for isotretinoin-loaded niosomal gel

Kinetic Model	Principle	Interpretation / Desired Outcome	Ref
Zero-order model	Drug is released at a constant rate independent of drug concentration.	Provides sustained drug release and maintains constant therapeutic levels.	81
First-order model	Drug release depends on the concentration of drug remaining in the formulation.	Release rate decreases as drug concentration declines.	82
Higuchi model	Drug release occurs by diffusion through the gel or matrix system.	Indicates diffusion-controlled drug release.	83
Korsmeyer–Peppas model	Empirical model used to analyze the mechanism of drug release.	Identifies whether release follows Fickian diffusion, non-Fickian (anomalous) transport, Case II transport, or erosion-controlled mechanisms.	84

 

 

12. Ex Vivo skin permeation and skin retention studies

Ex vivo skin permeation studies are essential for evaluating the penetration, retention and permeation behavior of isotretinoin-loaded niosomal gel across biological skin barriers. In this method, excised animal or human cadaver skin is mounted on Franz diffusion cells to simulate topical drug application under controlled laboratory conditions.⁸⁵ These studies quantify the amount of drug that permeates through the skin, is retained within the epidermis, dermis and pilosebaceous follicles and remains in the formulation over time.⁸⁶ Compared with conventional formulations, niosomal gels may exhibit enhanced drug deposition within the epidermis, dermis and pilosebaceous follicles while limiting systemic permeation.⁸⁷ 

 

 

Table 7. Evaluation parameters for Ex Vivo skin permeation

Parameter	Method/Instrument	Desired result	Ref
Skin permeation	Franz diffusion cell	Controlled drug permeation	88
Skin drug retention	Tape stripping / Skin extraction	High epidermal and dermal retention	89
Follicular deposition	Skin extraction / Microscopy	Enhanced pilosebaceous localization	90
Permeation flux	Franz diffusion cell	Sustained permeation rate	91
Systemic permeation	Drug assay (UV–Vis/HPLC)	Minimal transdermal absorption	92

 

 

13. Skin irritation and safety assessment

Safety evaluation is an essential component of isotretinoin-loaded niosomal gel development, particularly for formulations intended for long-term topical application. Skin irritation studies are performed to assess the potential for erythema, edema, dryness, itching and other local adverse reactions following repeated application.⁹³ 

14. Stability studies

Stability studies are essential to evaluate the ability of isotretinoin-loaded niosomal gel to maintain its physicochemical characteristics, drug content and therapeutic performance throughout its shelf life. These studies are performed under real-time and accelerated storage conditions in accordance with ICH stability guidelines to assess formulation integrity during storage.⁹⁴

 

 

Table 8. Stability evaluation parameters of isotretinoin-loaded niosomal gel

Parameter	Method/Instrument	Expected outcome	Ref
Appearance	Visual inspection	No phase separation, discoloration, or precipitation	95
Particle size	Dynamic Light Scattering (DLS)	Minimal or no significant change	96
Polydispersity Index (PDI)	Dynamic Light Scattering (DLS)	< 0.30 with minimal variation	97
Zeta potential	Zetasizer	≥ ±30 mV; maintained stability	98
pH	Digital pH meter	5.5–6.8 with no significant change	99
Viscosity	Brookfield viscometer	Stable viscosity throughout storage	100
Drug content	UV–Visible Spectrophotometry / HPLC	≥95% of initial drug content retained	101
Entrapment efficiency	UV–Visible Spectrophotometry / HPLC	Stable with minimal reduction during storage	102
In vitro drug release	Franz diffusion cell / Dissolution study	Comparable to the initial release profile	103

 

 

15. Recent advances in isotretinoin niosomal gel

Recent advances in pharmaceutical nanotechnology have substantially improved the design, optimization and therapeutic performance of isotretinoin-loaded niosomal gels.¹⁰⁴ Modern formulation strategies increasingly incorporate Quality by Design (QbD) and Design of Experiments (DoE) to systematically optimize critical material attributes (CMAs) and critical process parameters (CPPs), resulting in formulations with improved reproducibility, stability, and quality.¹⁰⁵ The development of novel non-ionic surfactants, edge activators and membrane stabilizers has enhanced vesicle deformability, drug encapsulation efficiency and skin penetration, thereby improving follicular targeting and sustained drug release.¹⁰⁶ In addition, the integration of artificial intelligence (AI) and machine learning (ML) has emerged as a promising approach for predicting formulation behavior, optimizing excipient selection and accelerating pharmaceutical product development while reducing experimental workload.¹⁰⁷ 

16. Future perspectives

Future research should focus on clinical validation, scale-up, long-term stability, regulatory approval and formulation standardization of isotretinoin-loaded niosomal gels. QbD, AI, personalized therapy, targeted niosomes and combination therapy may further improve efficacy and safety. These advances could support the clinical translation and commercialization of niosomal gels for acne management.

17. Conclusion

Isotretinoin-loaded niosomal gel is a promising topical system that improves isotretinoin stability, skin penetration, follicular targeting, retention and controlled release, while reducing irritation and systemic exposure. QbD, DoE and AI-assisted optimization can enhance formulation quality and reproducibility. Further research should focus on stability, clinical validation, scale-up and regulatory approval.

Abbreviations

AI : Artificial Intelligence

CMAs : Critical Material Attributes

cP : Centipoise

CPPs : Critical Process Parameters

DLS : Dynamic Light Scattering

DoE : Design of Experiments

DSC : Differential Scanning Calorimetry

EE : Entrapment Efficiency

ELS : Electrophoretic Light Scattering

FTIR : Fourier Transform Infrared Spectroscopy

H&E : Hematoxylin and Eosin

HLB : Hydrophilic–Lipophilic Balance

HPLC : High-Performance Liquid Chromatography

IL : Interleukin

Log P : Partition Coefficient

MAPK : Mitogen-Activated Protein Kinase

ML : Machine Learning

MLVs : Multilamellar Vesicles

MMPs : Matrix Metalloproteinases

NF-κB : Nuclear Factor-Kappa B

PBS : Phosphate-Buffered Saline

PDI : Polydispersity Index

pH : Potential of Hydrogen

pKa : Acid Dissociation Constant

QbD : Quality by Design

QTPP : Quality Target Product Profile

RAR : Retinoic Acid Receptor

ROS : Reactive Oxygen Species

RSM : Response Surface Methodology

RXR : Retinoid X Receptor

SEM : Scanning Electron Microscopy

TEM : Transmission Electron Microscopy

TLR : Toll-Like Receptor

TNF-α : Tumor Necrosis Factor-Alpha

ULV : Unilamellar Vesicle

UV : Ultraviolet

UV–Vis : Ultraviolet–Visible Spectrophotometry

XRD : X-Ray Diffraction

λmax : Maximum Absorption Wavelength

Ethics approval and consent to participate: As this manuscript is a literature-based narrative review and does not include original research involving human or animal subjects, approval from an institutional ethics committee and informed consent were not applicable.

Clinical Trial No: This study is a narrative review of published literature and does not include any clinical trial; therefore, clinical trial registration was not required.

Consent for publication: This study is a narrative review of published literature and does not include any clinical trial; therefore, clinical trial registration was not required.

Availability of data and material: This manuscript is a narrative review of published literature and does not involve the generation or analysis of original datasets. Consequently, no data are available for sharing.

Funding: The authors declare that no specific financial support was received from any public, commercial, or non- profit funding organization for the preparation of this review.

Declaration of competing interest: The authors declare that there are no conflicts of interest regarding  the publication of this manuscript.

Acknowledgements: The authors express their heartfelt gratitude to the Principal of Columbia Institute of Pharmacy, Columbia Professional University, Raipur, Chhattisgarh, India, and the Principal of Gracious College of Pharmacy, Village Belbhata, Abhanpur, Raipur, Chhattisgarh, India, for their continuous encouragement and for providing the infrastructure and library resources essential for completing this review.

Authorship contribution statement:

Ruchi Gupta: Writing-Review & Editing

Niharika sahu: Visualization, Schematic Representation, Graphical Abstract Preparation, Figure Design and Illustration.

Rahul Dev: Writing-Review & Editing, Critical Revision of the Manuscript.

Rupesh sahu: Literature Search, Data Curation, Validation and Manuscript Review.

Dharmendra sahu: Conceptualization, Methodology and Critical Review.

Shiv Kumar Bhardwaj: Conceptualization, Literature Search, Data Curation, Writing-Original Draft Preparation, Methodology, Visualization and Final Manuscript Editing.

References: 

1.     Del Rosso JQ, Kircik L. The primary role of sebum in the pathophysiology of acne vulgaris and its therapeutic relevance in acne management. Journal of Dermatological Treatment. 2024;35(1). doi:10.1080/09546634.2023.2296855

2.     Zhao Y, Liu L, Xiao Y, Jiao T, Wang R, Wang J. Dual drug-loaded dissolving microneedle combining photodynamic therapy and isotretinoin for enhanced acne vulgaris treatment. Int J Pharm. 2026;703:127311. doi:10.1016/j.ijpharm.2026.127311

3.     Yuniarsih N, Chaerunisaa A, Mohammed A, Elamin K, Muchtaridi M, Wathoni N. Nanoencapsulated α-Mangostin Loaded Chitosan-Alginate Hydrogel Films for Enhanced Topical Anti Acne Therapy. Drug Des Devel Ther. 2026;Volume 20:1-16. doi:10.2147/DDDT.S588115

4.     Petrovici AG, Spennato M, Bîtcan I, et al. A Comprehensive Review of Azelaic Acid Pharmacological Properties, Clinical Applications, and Innovative Topical Formulations. Pharmaceuticals. 2025;18(9):1273. doi:10.3390/ph18091273

5.     Xu F, Qiu Z, Zhang M, et al. Transdermal Drug Delivery Systems: A Comprehensive Review of Mechanisms, Technologies, and Clinical Applications. Pharm Res. 2025;42(12):2429-2442. doi:10.1007/s11095-025-03962-9

6.     Zhang Y, Shang Y, Bao J, Wang Y. Molecular pathogenesis of acne and their microneedle treatments. Engineered Regeneration. 2025;6:235-248. doi:10.1016/j.engreg.2025.11.001

7.     Dhiwar P, Satapathy T, Sahu AK, Patel N. Exploring the potential of herbal bioactives to treat acne: A perspective review. Pharmacological Research - Natural Products. 2025;7:100260. doi:10.1016/j.prenap.2025.100260

8.     Phytochemicals as emerging therapeutics for acne vulgaris: a comprehensive review.

9.     Aliashrafi M, Nasehi M, Siadat SD, Mohammadi-Mahdiabadi-Hasani MH, Zali H, Niknam Z. Cutibacterium Acnes induces Alzheimer’s disease-like pathology in brains of wistar rats through structural changes associated with microtubules. Behavioral and Brain Functions. 2024;20(1):30. doi:10.1186/s12993-024-00257-8

10.  Kusuma SAF. Selective Modulation of Cutibacterium acnes Biofilms in Acne: Limitations of Conventional Therapies and Emerging Anti-Virulence Strategies. Clin Cosmet Investig Dermatol. 2026;Volume 19:1-17. doi:10.2147/CCID.S621646

11.  Huang L, Yang S, Yu X, et al. Association of different cell types and inflammation in early acne vulgaris. Front Immunol. 2024;15. doi:10.3389/fimmu.2024.1275269

12.  Magkou S, Sali E, Paschou IA, et al. Skin manifestations of hyperandrogenism: an update. Hormones. Published online May 4, 2026. doi:10.1007/s42000-026-00785-0

13.  Paolino G, Caputo V, Stabile G, Bonoldi E, Rongioletti F. Widespread and eruptive comedonal lesions with alopecia. JAAD Case Rep. 2023;31:23-26. doi:10.1016/j.jdcr.2022.10.020

14.  Angulmaduwa S, Roshan Pradeep RGG, Kim YG, Lee JH, Lee J. Dihalogenated indoles with antimicrobial activity against C. acnes and polymicrobial biofilms. Microb Pathog. 2026;218:108685. doi:10.1016/j.micpath.2026.108685

15.  Cruz S, Vecerek N, Elbuluk N. Targeting Inflammation in Acne: Current Treatments and Future Prospects. Am J Clin Dermatol. 2023;24(5):681-694. doi:10.1007/s40257-023-00789-1

16.  Jomova K, Alomar SY, Alwasel SH, Nepovimova E, Kuca K, Valko M. Several lines of antioxidant defense against oxidative stress: antioxidant enzymes, nanomaterials with multiple enzyme-mimicking activities, and low-molecular-weight antioxidants. Arch Toxicol. 2024;98(5):1323-1367. doi:10.1007/s00204-024-03696-4

17.  Long A, Kleiner A, Looney RJ. Immune dysregulation. Journal of Allergy and Clinical Immunology. 2023;151(1):70-80. doi:10.1016/j.jaci.2022.11.001

18.  Ranjan R, Kumar V, Nagaraja S, Singh S, Pal R. Acne Vulgaris: Integrating Pathophysiology with Conventional, Herbal, and Nanocarrier-Based Therapeutic Strategies. Curr Pharm Des. 2026;32. doi:10.2174/0113816128461870260627145248

19.  Nurizan ANB, Baharom AM, Mohamed Ibrahim NH, et al. Emerging niosomal formulations for skin-targeted drug delivery: strategies, applications, and limitations. International Journal of Polymeric Materials and Polymeric Biomaterials. 2026;75(8):921-933. doi:10.1080/00914037.2026.2615461

20.  Abruzzo A, Pucci R, Abruzzo PM, et al. Azithromycin-loaded liposomes and niosomes for the treatment of skin infections: Influence of excipients and preparative methods on the functional properties. European Journal of Pharmaceutics and Biopharmaceutics. 2024;197:114233. doi:10.1016/j.ejpb.2024.114233

21.  Eugster R, Ganguin AA, Seidi A, Aleandri S, Luciani P. 3D printing injectable microbeads using a composite liposomal ink for local treatment of peritoneal diseases. Drug Deliv Transl Res. 2024;14(6):1567-1581. doi:10.1007/s13346-023-01472-y

22.  Eugster R, Luciani P. Liposomes: Bridging the gap from lab to pharmaceuticals. Curr Opin Colloid Interface Sci. 2025;75:101875. doi:10.1016/j.cocis.2024.101875

23.  Bautista-Solano AA, Dávila-Ortiz G, Perea-Flores M de J, Martínez-Ayala AL. A Comprehensive Review of Niosomes: Composition, Structure, Formation, Characterization, and Applications in Bioactive Molecule Delivery Systems. Molecules. 2025;30(17):3467. doi:10.3390/molecules30173467

24.  Hadjipour A, Essa EA, Elkordy AA. A glance into factors affecting the possible combined entrapment of curcumin and methylene blue into niosomal formulations as a potential anticancer therapy. J Drug Deliv Sci Technol. 2024;100:106120. doi:10.1016/j.jddst.2024.106120

25.  Mawazi SM, Ge Y, Widodo RT. Niosome Preparation Techniques and Structure—An Illustrated Review. Pharmaceutics. 2025;17(1):67. doi:10.3390/pharmaceutics17010067

26.  Basheer HA, Alkilani AZ, Alhusban MA, Abo-Zour H, Alshaer W. Evaluating Niosomes Cytotoxicity on Fibroblast Cells: A Preliminary Step Towards Cancer Cell Assessment Using Telaglenastat as a Model Drug. Bionanoscience. 2025;15(1):35. doi:10.1007/s12668-024-01739-9

27.  Ragheb RR, Atef R, Abdou K, Ahmed S, Fatouh AM. Harnessing Hybrid Niosomes for Improved Oral Bioavailability of an Anticoagulant: Design, Optimization and In-Vivo Pharmacokinetics and Pharmacodynamics Evaluations. AAPS PharmSciTech. 2026;27(3):171. doi:10.1208/s12249-026-03374-x

28.  Mawazi SM, Ann TJ, Widodo RT. Exploring the Evolution of Niosomes: from Past Techniques to Future Advances in Preparation Methods—a Comprehensive Review. Bionanoscience. 2024;14(2):1854-1875. doi:10.1007/s12668-024-01395-z

29.  Shahzad Yasser, Rizvi SAA., Yousaf AMehmood, Hussain Talib. Drug Delivery Using Nanomaterials. CRC Press; 2022.

30.  Sim YS, Wong LC, Yeoh SC, Almashhadani A, Alrimawi BH, Goh CF. Skin penetration enhancers: Mechanistic understanding and their selection for formulation and design. Drug Deliv Transl Res. 2025;15(11):3864-3898. doi:10.1007/s13346-025-01809-9

31.  Patel H, Jani R, Yadav S, Dave P, Dudhat K. Formulation and Characterization of Niosomal Carrier–Based Ivermectin Gel for Rosacea Therapy. Regen Eng Transl Med. Published online October 2, 2025. doi:10.1007/s40883-025-00494-x

32.  Anwar M, Muhammad F, Akhtar B, Fatima S, Khan H, Chou CC. Nanomedicines in the Treatment of Skin Diseases. In: 2023:285-306. doi:10.1007/978-981-99-7626-3_9

33.  Thakur RK, Kumar A, Aggarwal K, et al. A complete sojourn on nanotechnological advancements and nanocarrier applications in psoriasis management. Naunyn Schmiedebergs Arch Pharmacol. 2025;398(6):6453-6471. doi:10.1007/s00210-025-03804-w

34.  Bigham H, Pardakhty A, Sabouri S, Salarpour S, Sharififar F. Formulation and Physicochemical Characterisation of Niosomes Containing Standardized Hydroalcoholic Extracts of Eucalyptus (Eucalyptus galbie) and Green Tea (Camellia sinensis L.) with Potential Anti-Acne Effect. J Pharm Innov. 2026;21(1):22. doi:10.1007/s12247-025-10113-5

35.  Xu F, Li M, Ruan H, et al. TPGS Modified Phospholipid-free and Cholesterol-free Ethosomes Enhance Chemical Stability and Transdermal Permeation Of Retinol. AAPS PharmSciTech. 2026;27(3):177. doi:10.1208/s12249-026-03417-3

36.  Omidi M, Ghasabeh Siahkal-Mahaleh N, Rahimnia SM, et al. Arbutin-Loaded Solid Lipid Nanoparticles as Safe and Potent Green Biodegradable Nano systems for Melanin Synthesis Inhibition, Anti-Tyrosinase, and Antioxidant Effects. Bionanoscience. 2026;16(6):416. doi:10.1007/s12668-026-02657-8

37.  Manchanda D, Makhija M, Sharma M. A Comprehensive Review of Acne: Pathogenesis, Etiology, Treatment Approaches, and Recent Developments. Current Cosmetic Science. 2025;04. doi:10.2174/0126667797382894250907122020

38.  Mekasha YT, Feleke MG, Mohammed Y. Application of quality by design principles in topical semisolid formulations development: a systematic review of CQA, DoE, and control strategies. AAPS Open. 2026;12(1):39. doi:10.1186/s41120-026-00174-2

39.  Skin Penetration and Permeation Properties of Transcutol® in Complex Formulations.

40.  Tran BN, Nguyen NMH, Kieu TH, et al. PEG-modified Niosome–Hydrogel Patch System for Sustained Transdermal Delivery of Dexamethasone. J Pharm Innov. 2026;21(4):344. doi:10.1007/s12247-026-10588-w

41.  Phatak KM, Yawalkar AN, Vavia PR. From bench to bulk: exploring in-line homogenization for scale-up and continuous production of vesicular systems. Drug Deliv Transl Res. Published online January 30, 2026. doi:10.1007/s13346-026-02045-5

42.  Shaddel R, Akbari-Alavijeh S, Cacciotti I, et al. Caffeine-loaded nano/micro-carriers: Techniques, bioavailability, and applications. Crit Rev Food Sci Nutr. 2024;64(15):4940-4965. doi:10.1080/10408398.2022.2147143

43.  Modgil M, Sharma A. Emerging Era in Colloidal Carriers Approach for Enhanced Transdermal Drug Delivery. Curr Nanosci. 2024;21(2):218-241. doi:10.2174/0115734137287023240103063237

44.  Tayal S, Tiwari P, Pratap Singh U, Dubey S, Vishwakarma R. A Review on Formulation, Characterization and Applications of Nanoemulsion. Asian Journal of Applied Science and Technology. 2024;08(01):67-84. doi:10.38177/ajast.2024.8106

45.  Pal R, Pandey P, Chawra HS, Singh RP. Niosomal as Potential Vesicular Drug Nano-carriers for the Treatment of Tuberculosis (TB). Nanoscience & Nanotechnology-Asia. 2025;15(1). doi:10.2174/0122106812323829240919050438

46.  Chaurasiya A, Gorajiya A, Panchal K, Katke S, Singh AK. A review on multivesicular liposomes for pharmaceutical applications: preparation, characterization, and translational challenges. Drug Deliv Transl Res. 2022;12(7):1569-1587. doi:10.1007/s13346-021-01060-y

47.  A review of topical micro- and nanoemulsions for common skin diseases .

48.  Dragicevic N, Maibach HI. Liposomes and Other Nanocarriers for the Treatment of Acne Vulgaris: Improved Therapeutic Efficacy and Skin Tolerability. Pharmaceutics. 2024;16(3):309. doi:10.3390/pharmaceutics16030309

49.  Chettupalli AK, Bukke SPN, Abdul Rahaman S, et al. Design, optimization of Niosomal gel capability for solubility and bioavailability enhancement of Kynurenic acid after intranasal administration: In Vitro and In Vivo Evaluation. BMC Biotechnol. 2025;25(1):134. doi:10.1186/s12896-025-01069-y

50.  Rajak P, Kimneiniang N, Sarma S, Bhuyan B, Pathak H. A Comprehensive Overview of Nanoparticles in Acne Management: Current Trends and Future Prospects. Current Cosmetic Science. 2025;04. doi:10.2174/0126667797362809250421114627

51.  Choudhary B, Banweer J. Selection of excipients for Ethosome Formulations of Imiquimod through Drug–excipient Compatibility testing for Skin Cancer: A Pre-Formulation Study. Res J Pharm Technol. 2026;19(1):426. doi:10.52711/0974-360X.2026.00062

52.  Shrestha N, Banga AK. Novel Formulation Approaches in the Topical Delivery System. In: 2025:241-270. doi:10.1007/978-3-031-80525-7_10

53.  Shi J, Wu J, Xu L, Tang C, Zhang Y. Artificial Intelligence-Enabled Intelligent Sensory Systems for Quality Evaluation of Traditional Chinese Medicine: A Review of Electronic Nose, Electronic Tongue, and Machine Vision Approaches. Molecules. 2026;31(7):1140. doi:10.3390/molecules31071140

54.  Pacheco A, Attard T, Calvert D, et al. Green Solvent Selection for Emulsifiable Concentrate Agrochemical Formulations. Org Process Res Dev. 2024;28(1):132-136. doi:10.1021/acs.oprd.3c00211

55.  Hu Y, Xu Y an, Feng H, Gao S, Zhou C, Zhu Z. Quantitative filling of high-purity rubidium into vapor cells via a zoned temperature gradient: Simulation and experimental validation. Measurement. 2026;290:122684. doi:10.1016/j.measurement.2026.122684

56.  Orzel D, Ravald H, Dillon A, Rantala J, Wiedmer SK, Russo G. Immobilised artificial membrane liquid chromatography vs liposome electrokinetic capillary chromatography: Suitability in drug/bio membrane partitioning studies and effectiveness in the assessment of the passage of drugs through the respiratory mucosa. J Chromatogr A. 2024;1734:465286. doi:10.1016/j.chroma.2024.465286

57.  Baikété J, Malloum A, Conradie J. pKa prediction for small molecules: an overview of experimental, quantum, and machine learning-based approaches. J Comput Aided Mol Des. 2026;40(1):5. doi:10.1007/s10822-025-00719-9

58.  Srivastava N, Bansal A, Aggarwal K, Nagpal K. Development and Validation of UV Spectrophotometric Method for the Quantitative Estimation of Quercetin in Bulk Followed by Its Solubility Studies. J Appl Spectrosc. 2024;91(3):700-708. doi:10.1007/s10812-024-01773-1

59.  Awasthi G, Banerjee S. In silico preformulation studies, including drug-excipient interaction or compatibility studies, using an AI-based computational model and expert system. AAPS Open. 2026;12(1):30. doi:10.1186/s41120-026-00164-4

60.  Kashinath KP, Sardar MS, Sah SK, Kaity S. Stability and accelerated stability studies of dosage forms. In: Physico-Chemical Aspects of Dosage Forms and Biopharmaceutics. Elsevier; 2024:19-42. doi:10.1016/B978-0-323-91818-3.00001-3

61.  Kumar P, Verma N, Diksha, Singh P, Mishra G. Follicular targeting through nanotechnology: An overview. In: Nanodermatology. Elsevier; 2026:377-398. doi:10.1016/B978-0-443-36326-9.00014-9

62.  Palanisamy P, Crossia WF, Prakash D, Antonyraj APM. Nanoformulation of stavudine-loaded niosomes: Enhancing drug delivery, entrapment efficiency, and controlled release for improved antiretroviral therapy. Journal of Orthopaedic Reports. 2026;5(1):100677. doi:10.1016/j.jorep.2025.100677

63.  Shiri S, Gharanjig K, Tahghighi A, Hosseinnezhad M, Etezad M. Formulation and characterization of BBR loaded niosomes using saponin as a nonionic biosurfactant investigating synergistic effects to enhance antibacterial activity. Sci Rep. 2025;15(1):5231. doi:10.1038/s41598-025-87950-4

64.  Garg G, Garg S, Patel P, Gupta G Das, Kurmi B Das. Advances in solid-lipid nanoparticle chemistry as drug delivery vehicles. International Journal of Polymeric Materials and Polymeric Biomaterials. 2025;74(6):523-537. doi:10.1080/00914037.2024.2344603

65.  Wafiq Mohamed N, Sabry SA, Mahdy MA, Faisal MM. Tailoring of spanlastics for promoting transdermal delivery of irbesartan: In vitro characterization, ex vivo permeation and in vivo assessment. J Drug Deliv Sci Technol. 2024;100:106088. doi:10.1016/j.jddst.2024.106088

66.  Kumar D, Sil D, Kurmi B Das, Kumar M. Future Prospects and Regulatory Pathways for Invasome Technologies in Transdermal Drug Delivery. Assay Drug Dev Technol. 2025;23(3):115-135. doi:10.1089/adt.2024.080

67.  Hajinezhad MR, Roostaee M, Nikfarjam Z, et al. Exploring the potential of silymarin-loaded nanovesicles as an effective drug delivery system for cancer therapy: in vivo, in vitro, and in silico experiments. Naunyn Schmiedebergs Arch Pharmacol. 2024;397(9):7017-7036. doi:10.1007/s00210-024-03099-3

68.  Ma B, Shu Q, Zhang W, Li L, Liu Y. Comparative evaluation of liposome and ergosterol-niosome systems for encapsulation of goat milk protein hydrolysates: Structural properties, in vitro digestive stability, and storage stability. Int J Biol Macromol. 2026;349:150869. doi:10.1016/j.ijbiomac.2026.150869

69.  Bunaciu AA, Hoang VD, Aboul-Enein HY. Fourier transform infrared spectroscopy used in drug excipients compatibility studies. Appl Spectrosc Rev. 2025;60(5):385-403. doi:10.1080/05704928.2024.2438747

70.  Mawazi SM, Widodo RT. Unravelling the Absence of Testosterone Peak in Niosomes Using DSC; Insights from FTIR and HRTEM Investigations. Bionanoscience. 2024;14(5):5094-5105. doi:10.1007/s12668-024-01591-x

71.  Dhal S, Cerqueira MA, Kim D, Pal K. Bigels: An Innovative Hybrid of Hydrogels/Oleogels for Food Applications. In: Advances in Oleogel Development, Characterization, and Nutritional Aspects. Springer International Publishing; 2024:327-348. doi:10.1007/978-3-031-46831-5_14

72.  Badran MM, Alsubaie A, Salem Bekhit MM, et al. Bioadhesive hybrid system of niosomes and pH sensitive in situ gel for itraconazole ocular delivery: Dual approach for efficient treatment of fungal infections. Saudi Pharmaceutical Journal. 2024;32(12):102208. doi:10.1016/j.jsps.2024.102208

73.  Jafarian A, Khalilabadi S, Shadloo A, Peyvandi K. The Influence of Operational Parameters on the Characterization of Tretinoin-Loaded Niosomes. ACS Omega. 2025;10(28):30031-30045. doi:10.1021/acsomega.4c11147

74.  Luthfi MA, Husna IT, Dahlizar S, Meliana Y, Septama AW. Innovative Niosome Gel Loaded Curcuma Xanthorrhiza Extract: Development Formulation, Characterization, and Evaluation of Their Antibacterial Activity. J Pharm Innov. 2026;21(1):28. doi:10.1007/s12247-025-10260-9

75.  Zaid Alkilani A, Sharaire Z, Hamed R, Basheer HA. Transdermal Delivery System of Doxycycline-Loaded Niosomal Gels: Toward Enhancing Doxycycline Stability. ACS Omega. 2024;9(31):33542-33556. doi:10.1021/acsomega.4c01224

76.  Gupta A, Kohli K, Mir SR, Khan R, Alhalmi A, Amin S. pH Responsive Trimethyl Chitosan Nanogels Enhance Site-Specific Fluocinolone Acetonide Delivery for Psoriasis Therapy. Bionanoscience. 2026;16(3):184. doi:10.1007/s12668-025-02338-y

77.  Fahimnia F, Nemattalab M, Hesari Z. Development and characterization of a topical gel, containing lavender (Lavandula angustifolia) oil loaded solid lipid nanoparticles. BMC Complement Med Ther. 2024;24(1):155. doi:10.1186/s12906-024-04440-2

78.  Deshmukh V, Pore Y V., Shikalgar R, Bangale GS, Rathod S, Pawar DP. Optimizing Nimesulide Loaded Cubosomal Gel for Enhanced Efficacy: A Systematic Engineering Approach with Factorial Design for Topical Applications. J Pharm Innov. 2024;19(4):40. doi:10.1007/s12247-024-09847-5

79.  Vitore JG, Nunse D, Aras G, Rupareliya M, Giram P. Prospects of nanotechnology in cosmeceuticals. In: Nanotechnology in Cosmeceuticals. Elsevier; 2026:457-471. doi:10.1016/B978-0-443-30184-1.00005-3

80.  Keservani RK., Scherer Santos Julia. Novel Nanocarriers for Skin Diseases : Advances and Applications. Apple Academic Press; 2025.

81.  Ali KA, Chakraborty R, Roy SKr, Ghosal K. Design and development of Ondansetron-loaded polysaccharide-based buoyant formulation for improved gastric retention and drug release, using both natural and semi-synthetic polymers. Int J Biol Macromol. 2025;305:141105. doi:10.1016/j.ijbiomac.2025.141105

82.  Mita N, Kang X, Chen P, et al. Injectable PLGA-based In Situ Forming Subconjunctival Implant for Sustained Ocular Delivery of Ketotifen Fumarate: Formulation, Drug Release, and Biocompatibility Studies. AAPS PharmSciTech. 2025;26(5):153. doi:10.1208/s12249-025-03142-3

83.  Supaphol P. Multicomponent Interactive Release (MIR) Model for Herbal Extract/Multidrug-Loaded Electrospun Nanofibers: A Mechanistic Framework Integrating Diffusion, Swelling, and Erosion. AAPS J. 2026;28(3):79. doi:10.1208/s12248-026-01225-y

84.  Ortiz-Ortiz DN, Mokarizadeh AH, Nikjou S, Tsige M, Joy A. Release Dynamics of Folic Acid from Peptidomimetic Polyesters: A Multi-Scale Investigation from Bulk Properties to Molecular Interactions. Biomacromolecules. 2026;27(2):1362-1374. doi:10.1021/acs.biomac.5c01977

85.  Patel M, Patel A, Desai J, Patel S. Cutaneous Pharmacokinetics of Topically Applied Novel Dermatological Formulations. AAPS PharmSciTech. 2024;25(3):46. doi:10.1208/s12249-024-02763-4

86.  Brito S, Baek M, Bin BH. Skin Structure, Physiology, and Pathology in Topical and Transdermal Drug Delivery. Pharmaceutics. 2024;16(11):1403. doi:10.3390/pharmaceutics16111403

87.  Thilagam NBS, Karthik VP, Gnanasambandan R, Sowmya C. A Comprehensive Review on Strategies of Topical Niosomes and Their Synergistic Effect for Enhanced Therapeutic Outcomes. Pharm Nanotechnol. 2026;14(1):29-44. doi:10.2174/0122117385345369241212071947

88.  Albuquerque LFF, Lins F V., Bispo ECI, et al. Ibrutinib topical delivery for melanoma treatment: The effect of nanostructured lipid carriers’ composition on the controlled drug skin deposition. Colloids Surf B Biointerfaces. 2024;237:113875. doi:10.1016/j.colsurfb.2024.113875

89.  Tomar Y, Maheshwari S, Gorantla S, Singhvi G. Curcumin loaded liquid crystalline nanoparticles for enhanced topical application: Design, characterization, ex vivo and dermatokinetic evaluation. J Drug Deliv Sci Technol. 2024;92:105391. doi:10.1016/j.jddst.2024.105391

90.  Sadeghi MS, Jabarimani N, Behrouzfar H, Dorkoosh F, Akbari Javar H. Finasteride-loaded phospholipid–bile salt mixed micelles for targeted follicular delivery in androgenetic alopecia. J Drug Target. Published online June 24, 2026:1-12. doi:10.1080/1061186X.2026.2622535

91.  Champmartin C, Seiwert C, Aubertin M, et al. Percutaneous absorption of two bisphenol a analogues, BPAF and TGSA: Novel In vitro data from human skin. Chemosphere. 2024;367:143564. doi:10.1016/j.chemosphere.2024.143564

92.  Tekade A, Shewale A, Shivakumar HN, Shinde R, Nimbalkar J. Cubosomes as Versatile Multifunctional Lipid-Based Nanocarriers for Drug Delivery: A Comprehensive Review. Curr Pharm Des. 2026;32. doi:10.2174/0113816128448670260318044416

93.  Plugariu IA, Bercea M, Gradinaru LM. New Gel Approaches for the Transdermal Delivery of Meloxicam. Gels. 2025;11(7):500. doi:10.3390/gels11070500

94.  Milosheska D, Roškar R. Use of Retinoids in Topical Antiaging Treatments: A Focused Review of Clinical Evidence for Conventional and Nanoformulations. Adv Ther. 2022;39(12):5351-5375. doi:10.1007/s12325-022-02319-7

95.  Ng ZJ, Goh CF, Mokhtar AMA, Ramli RNB, Lee CK, Tan JS. Microemulsion-based formulation of enterocin CC2: a novel antimicrobial solution targeting Streptococcus mutans. Drug Deliv Transl Res. 2025;15(10):3607-3625. doi:10.1007/s13346-025-01823-x

96.  Shen H, Huang S, Li R, et al. Development and validation of a static multiple light scattering (SMLS) method for real-time colloidal stability assessment in nanoparticle formulations. J Pharm Anal. 2026;16(3):101396. doi:10.1016/j.jpha.2025.101396

97.  Battisti AP, de Matos Fonseca J, Valencia GA, et al. Antifungal nanoemulsions based on basil essential oil stabilized with saponins extracted from Quillaja lancifolia. J Mol Liq. 2026;443:129151. doi:10.1016/j.molliq.2025.129151

98.  Wu X, Zhang J, Wang M, et al. Effect of emulsifier type on camellia oil-based nanostructured lipid carriers for delivery of curcumin. Food Chem. 2025;482:144193. doi:10.1016/j.foodchem.2025.144193

99.  Mahmood MB, Bdaiwi W, Dheyab MA. Stability-guided green tea (Camellia sinensis) mediated synthesis of gold nanoparticles: SPR-guided optimization and in vitro anticancer evaluation. Inorg Chem Commun. 2026;188:116601. doi:10.1016/j.inoche.2026.116601

100.                    Thakker AM, Sun D. Plant-based ink properties and storage stability for inkjet printing. Environmental Science and Pollution Research. 2024;31(5):8099-8117. doi:10.1007/s11356-023-31714-y

101.                    Panjwani D, Patel A, Mishra D, et al. Green RP-HPLC method for the estimation of carfilzomib in bulk, protein nanocarriers and human plasma: Application of chemometrics and Monte-Carlo simulations. Journal of Chromatography B. 2024;1249:124350. doi:10.1016/j.jchromb.2024.124350

102.                    Liu X, Lin X, Wei Y, Fei T, Hu X, Wang L. Enhancing the stability and bio-accessibility of carotenoids extracted from canistel (Lucuma nervosa) via liposomes encapsulation. LWT. 2024;204:116455. doi:10.1016/j.lwt.2024.116455

103.                    Palakurthi SS, Charbe NB, Kapre S, et al. Evaluating critical quality attributes and novel drug release testing of difluprednate nanoemulsions. Int J Pharm. 2025;674:125431. doi:10.1016/j.ijpharm.2025.125431

104.                    Keservani RK., Scherer Santos Julia. Novel Nanocarriers for Skin Diseases : Advances and Applications. Apple Academic Press; 2025.

105.                    Kaur P, Kriplani P. Optimizing Transdermal Drug Delivery with Novasome Nanocarriers: A Quality by Design (QbD) Framework. Curr Drug Deliv. 2026;23(4):440-461. doi:10.2174/0115672018367563250318083438

106.                    Sharma S, Garg A, Agrawal R, Chopra H, Pathak D. A Comprehensive Review on Niosomes as a Tool for Advanced Drug Delivery. Pharm Nanotechnol. 2024;12(3):206-228. doi:10.2174/2211738511666230726154557

107.                    Warke S, Katari O, Jain S. Current Status on the Convergence of Artificial Intelligence and Formulation Development in Industry: A Review. AAPS PharmSciTech. 2025;27(1):44. doi:10.1208/s12249-025-03296-