Repurposing celecoxib for colorectal cancer targeting via pH-triggered ultra-elastic nanovesicles: Pronounced efficacy through up-regulation of Wnt/ß-catenin pathway in DMH-induced tumorigenesis.

Celecoxib (CLX), a selective inhibitor for cyclooxygenase 2 (COX-2), has manifested potential activity against diverse types of cancer. However, low bioavailability and cardiovascular side effects remain the major challenges that limit its exploitation. In this work, we developed ultra-elastic nanovesicles (UENVs) with pH-triggered surface charge reversal traits that could efficiently deliver CLX to colorectal segments for snowballed tumor targeting. CLX-UENVs were fabricated via a thin-film hydration approach. The impact of formulation factors (Span 80, Tween 80, and sonication time) on the nanovesicular features was evaluated using Box-Behnken design, and the optimal formulation was computed. The optimum formulation was positively coated with polyethyleneimine (CLX-PEI-UENVs) and then coated with Eudragit S100 (CLX-ES-PEI-UENVs). The activity of the optimized nano-cargo was explored in 1,2-dimethylhydrazine-induced colorectal cancer in Wistar rats. Levels of COX-2, Wnt-2 and ß-catenin were assessed in rats' colon. The diameter of the optimized CLX-ES-PEI-UENVs formulation was 253.62 nm, with a zeta potential of -23.24 mV, 85.64% entrapment, and 87.20% cumulative release (24 h). ES coating hindered the rapid release of CLX under acidic milieu (stomach and early small intestine) and showed extended release in the colon section. In colonic environments, the ES coating layer was removed due to high pH, and the charge on the nanovesicular corona was shifted from negative to positive. Besides, a pharmacokinetics study revealed that CLX-ES-PEI-UENVs had superior oral bioavailability by 2.13-fold compared with CLX suspension. Collectively, these findings implied that CLX-ES-PEI-UENVs could be a promising colorectal-targeted nanoplatform for effective tumor management through up-regulation of the Wnt/ß-catenin pathway.

Innovative pulmonary targeting of terbutaline sulfate-laded novasomes for non-invasive tackling of asthma: statistical optimization and comparative in vitro/in vivo evaluation.

Asthma represents a globally serious non-communicable ailment with significant public health outcomes for both pediatrics and adults triggering vast morbidity and fatality in critical cases. The ß2-adrenoceptor agonist, terbutaline sulfate (TBN), is harnessed as a bronchodilator for monitoring asthma noising symptoms. Nevertheless, the hepatic first-pass metabolism correlated with TBN oral administration mitigates its clinical performance. Likewise, the regimens of inhaled TBN dosage forms restrict its exploitation. Consequently, this work is concerned with the assimilation of TBN into a novel non-phospholipid nanovesicular paradigm termed novasomes (NVS) for direct and effective TBN pulmonary targeting. TBN-NVS were tailored based on the thin film hydration method and Box-Behnken design was applied to statistically optimize the formulation variables. Also, the aerodynamic pattern of the optimal TBN-NVS was explored via cascade impaction. Moreover, comparative pharmacokinetic studies were conducted using a rat model. TBN elicited encapsulation efficiency as high as 70%. The optimized TBN-NVS formulation disclosed an average nano-size of 223.89 nm, ζ potential of -31.17 mV and a sustained drug release up to 24 h. Additionally, it manifested snowballed in vitro lung deposition behavior in cascade impactor with a fine particle fraction of 86.44%. In vivo histopathological studies verified safety of intratracheally-administered TBN-NVS. The pharmacokinetic studies divulged 3.88-fold accentuation in TBN bioavailability from the optimum TBN-NVS versus the oral TBN solution. Concisely, the results proposed that NVS are an auspicious nanovector for TBN pulmonary delivery with integral curbing of the disease owing to target specificity.

A novel nanogel loaded with chitosan decorated bilosomes for transdermal delivery of terbutaline sulfate: artificial neural network optimization, in vitro characterization and in vivo evaluation.

The objective of the present work was to formulate, optimize, and evaluate transdermal terbutaline sulfate (TBN)-loaded bilosomes (BLS) in gel, compared to conventional oral TBN solution and transdermal gel loaded with free TBN, aiming at evading the hepatic first-pass metabolism. A face-centered central composite design was adopted to observe the effects of different formulation variables on TBN-BLS, and artificial neural network (ANN) modeling was employed to optimize TBN-BLS. TBN-BLS were prepared by a thin film hydration method integrating soybean phosphatidylcholine and cholesterol as a lipid phase and sodium deoxycholate (SDC) as a surfactant with or without the coating of chitosan (CTS). After being subjected to physicochemical characterization, TBN-BLS were enrolled in a histopathological study and pharmacokinetic investigation in a rat model. The optimized TBN chitosan-coated bilosomes (TBN-CTS-BLS) were spherical vesicles (245.13 ± 10.23 nm) with adequate entrapment efficiency (65.25 ± 5.51%) and good permeation characteristics (340.11 ± 22.34 µg/cm2). The TBN-CTS-BLS gel formulation was well-tolerated with no inflammatory signs manifested upon histopathological evaluation. The pharmacokinetic study revealed that the optimized TBN-CTS-BLS formulation successively enhanced the bioavailability of TBN by about 2.33-fold and increased t1/2 to about 6.21 ± 0.24 h as compared to the oral solution. These findings support the prospect use of BLS as active and safe transdermal carrier for TBN in the treatment of asthma. Graphical Abstract.

A novel transdermal nanoethosomal gel of lercanidipine HCl for treatment of hypertension: optimization using Box-Benkhen design, in vitro and in vivo characterization.

Poor bioavailability of drugs via oral route is the greatest challenge facing drug formulation. To overcome this obstacle, transdermal route was commonly used as an alternative route to improve bioavailability. Lercanidipine HCl (LER) is a vasoselective calcium-channel blocker that has a poor oral bioavailability of 10% due to its hepatic metabolism and low solubility. The main objective of this study was to develop nanoethosomal LER gel for transdermal delivery to increase its skin permeation and promote bioavailability. Nanoethosomes were prepared and optimized using a Box-Behnken design employing ethanol injection method. The design studied the influence of Phospholipon 90G (PL90G), LER, and ethanol concentrations on entrapment efficiency (EE%); vesicle size; % cumulative LER release (CLERR); and cumulative LER permeated per unit area at 24 h Q24 (µg/cm2). The pharmacokinetic parameters of the optimized formulation were determined in rats. Nanoethosomes showed a mean vesicle size between 210.87 and 400.57 nm and EE% ranging from 49.26 to 97.22%. The developed nanoethosomes enhanced % CLERR and Q24 values compared to drug suspension. The experimental parameters of optimized formulation were very close to those calculated by software. The pharmacokinetics study showed three times statistically significant (p < 0.05) enhancement in LER bioavailability following nanoethosomal LER gel transdermal application compared to that of oral LER suspension. Nanoethosomes can be considered as a promising carrier for LER transdermal delivery, thus will be fruitful therapy in hypertension management. Graphical abstract.

Correction to: A novel transdermal nanoethosomal gel of lercanidipine HCl for treatment of hypertension: optimization using Box-Benkhen design, in vitro and in vivo characterization.

In the original article, there are errors in Tables 2 and 6. Following are the corrected tables.

Transdermal delivery of fluvastatin sodium via tailored spanlastic nanovesicles: mitigated Freund's adjuvant-induced rheumatoid arthritis in rats through suppressing p38 MAPK signaling pathway.

The current study aimed to encapsulate fluvastatin sodium (FVS), a member of the statins family possessing pleiotropic effects in rheumatoid arthritis (RA), into spanlastic nanovesicles (SNVs) for transdermal delivery. This novel delivery could surmount FVS associated oral encumbrances such as apparent first-pass effect, poor bioavailability and short elimination half-life, hence, accomplishing platform for management of RA. To consummate this objective, FVS-loaded SNVs were elaborated by thin film hydration method, utilizing either Span 60 or Span 80, together with Tween 80 or Brij 35 as an edge activator according to full factorial design (24). Applying Design-Expert® software, the influence of formulation variables on SNVs physicochemical properties and the optimized formulation selection were explored. Additionally, the pharmacokinetic studies were scrutinized in rats. Furthermore, in Freund's adjuvant-induced arthritis, rheumatoid markers, TNF-α, IL-10, p38 MAPK, and antioxidant parameters were measured. The optimum SNVs were nano-scaled spherical vesicles (201.54 ± 9.16 nm), having reasonable entrapment efficiency (71.28 ± 2.05%), appropriate release over 8 h (89.45 ± 3.64%) and adequate permeation characteristics across the skin (402.55 ± 27.48 µg/cm2). The pharmacokinetic study disclosed ameliorated bioavailability of the optimum SNVs gel by 2.79- and 4.59-fold as compared to the oral solution as well as the traditional gel, respectively. Moreover, it elicited a significant suppression of p38 MAPK expression and also significant improvement of all other measured biomarkers. Concisely, the foregoing findings proposed that SNVs can be auspicious for augmenting FVS transdermal delivery for management of RA.

Development, Optimization, and In Vitro/In Vivo Characterization of Enhanced Lipid Nanoparticles for Ocular Delivery of Ofloxacin: the Influence of Pegylation and Chitosan Coating.

This study aims to investigate whether modification of solid lipid nanoparticles (SLNs) with chitosan (CTS) and polyethylene glycol (PEG) coatings enhances corneal retention time and transcorneal bioavailability. Ofloxacin (OFLOX) was selected as the model drug because of its potential benefits for the treatment of local eye infections. The OFLOX-CTS-PEG-SLN was prepared by a modified emulsion/solvent evaporation technique. A central composite design was implemented to investigate the influence of total lipid/drug ratio, surfactant concentration, PEG stearate concentration in the lipid mixture, and CTS concentration on size, entrapment, transcorneal permeation, and adhesion to the corneal mucosal membrane. The optimized OFLOX-CTS-PEG-SLN was characterized for OFLOX cumulative percentage released in simulated tear fluid and permeated across the excised bovine corneal membrane. Moreover, nanoparticle morphology, eye irritation via histopathological analysis, and OFLOX concentration in the ocular fluids and tissues were determined. A total lipid/drug ratio of 19:1, Tween 80 of 2%, PEG stearate concentration in the lipid mixture (% w/w) of 2.6%, and CTS concentration (% w/v) of 0.23% produced 132.9 nm particles entrapping 74.8% of the total drug added. The particles detached from the corneal membrane at a force of 3700 dyne/cm2. The %OFLOX released from the optimized nanoparticles was 63.3, and 66% of the drug permeated after 24 h. Compared to Oflox® drops, the optimized OFLOX-CTS-PEG-SLN exhibited similar tolerability but two- to threefold higher concentrations in the eyes of rabbits. Coating of SLN with chitosan and PEG augments the ocular bioavailability of OFLOX by increasing transcorneal permeation and enhancing mucoadhesion strength.

Comparison of Three Different Concentrations of Levobupivacaine for Epidural Labor Analgesia: Clinical Effect and Pharmacokinetic Profile.

BACKGROUND: The aim is to compare the clinical effect of three different concentrations of levobupivacaine (0.25%, 0.125%, and 0.0625%) on the sensory and motor block characteristics and mode of delivery during epidural labor analgesia. We also studied the pharmacokinetic profile of the three concentrations during labor. MATERIALS AND METHODS: Sixty pregnant females undergoing normal vaginal delivery under epidural analgesia were divided into three groups according to the concentration of levobupivacaine used. All parturients received an epidural bolus dose of 15 ml of the desired concentration followed by a continuous infusion of the same concentration at 10 mL/h, each combined with fentanyl 2 µg/mL. Sensory block was assessed by the visual analog score (VAS), whereas motor block was evaluated by the Bromage score. Assessments were performed every 5 min in the first 20 min after initiation of epidural analgesia and then at 30 min interval. The incidence of instrumental delivery and cesarean section was also recorded. The total plasma concentrations of levobupivacaine were determined before the start of epidural analgesia, 5 and 10 min after starting the infusion, at infusion stop time, and 3-8 h after infusion termination. RESULTS: The VAS was significantly lower with levobupivacaine concentrations of 0.25% and 0.125% than 0.0625%. Motor block in the form of Bromage score 1 was observed in 39% of parturients receiving levobupivacaine 0.25% of which 43% were converted to cesarean delivery. No motor block was observed with the other two concentrations. Levobupivacaine peak plasma concentrations increased with increasing the concentration of the local anesthetic. There was no difference in other pharmacokinetic parameters between the three groups. CONCLUSION: levobupivacaine concentration of 0.125% is superior to other concentrations for epidural labor analgesia as it provides adequate analgesia without motor affection which reflects in a lower incidence of instrumental delivery or cesarean section.

Nanosized soy phytosome-based thermogel as topical anti-obesity formulation: an approach for acceptable level of evidence of an effective novel herbal weight loss product.

PURPOSE: Herbal supplements are currently available as a safer alternative to manage obesity, which has become a rising problem over the recent years. Many chemical drugs on the market are designed to prevent or manage obesity but high cost, low efficacy, and multiple side effects limit its use. Nano lipo-vesicles phytosomal thermogel of Soybean, Glycine max (L.) Merrill, was formulated and evaluated in an attempt to investigate its anti-obesity action on body weight gain, adipose tissue size, and lipid profile data. METHODS: Three different techniques were used to prepare phytosome formulations including solvent evaporation, cosolvency, and salting out. The optimized phytosome formulation was then selected using Design Expert® (version 7.0.0) depending on the highest entrapment efficiency, minimum particle size (PS), and maximum drug release within 2 hours as responses for further evaluation. The successful phytosome complex formation was investigated by means of Fourier-transform infrared spec troscopy and determination of PS and zeta potential. Phytosome vesicles' shape was evaluated using transmission electron microscope to ensure its spherical shape. After characterization of the optimized phytosome formulation, it was incorporated into a thermogel formulation. The obtained phytosomal thermogel formulation was evaluated for its clarity, homogeneity, pH, and gel transformation temperature besides rheology behavior and permeation study. An in vivo study was done to investigate the anti-weight-gain effect of soy phytosomal ther mogel. RESULTS: EE was found to be >99% for all formulations, PS ranging from 51.66-650.67 while drug release was found to be (77.61-99.78) in range. FTIR and TEM results confirmed the formation of phytosome complex. In vivo study showed a marked reduction in body weight, adipose tissue weight and lipid profile. CONCLUSION: Concisely, soy phytosomal thermogel was found to have a local anti-obesity effect on the abdomen of experimental male albino rats with a slight systemic effect on the lipid profile data.

Betahistine dihydrochloride transdermal delivery via optimized thermosensitive gels: percutaneous absorption evaluation using rat growth as a biomarker.

The aim of this study was to develop and optimize a betahistine dihydrochloride (BH) thermoreversible bioadhesive gel intended for transdermal delivery. The gels were obtained via cold method. A full factorial design was employed to investigate the joint effect of Poloxamer 407 concentration (18 and 20%), adhesive polymer type (Polyvinyl pyrolidone, Hydroxypropyl methylcellulose, and Carbopol 934), and adhesive polymer concentration (0.5 and 1.5%) on gelling temperature, viscosity at 37 °C, and adhesion strength. Data collected were analyzed using multiple linear regression. A desirability index approach with relative importance weight was used to choose the most desirable formulation. F4 (20% Poloxamer+1.5% Carbopol) was selected for further characterization. F4 released 96.97% drug in 12 h across hairless rat skin. F4 gelation temperature and time were 36 ± 0.35 °C, and 6 ± 0.7 min, respectively. F4 adhesive force was 8835.68 dyne/cm2. F4 was tested for its appetite suppressing effect in a rat model and it was evaluated histopathologically. Rats' chow intake and weight gain was significantly decreased with no signs of inflammation or lipolysis when the optimized BH gel formulation, F4, was compared with untreated animals and animals treated with BH free gel. The results suggest that BH is percutaneously absorbed from the gel base and that the BH gel is tolerable. The desirability index approach with relative importance weight of responses was effective in determination of the optimum formulation. BH is systemically effective and well-tolerated when applied topically in hydrogel-based systems. The Carbopol-Poloxamer gel is a promising modality for transdermal delivery of BH.

A novel transdermal nanoethosomal gel of betahistine dihydrochloride for weight gain control: in-vitro and in-vivo characterization.

BACKGROUND: Betahistine dihydrochloride (BDH) is a histamine analog used to control weight gain, with short elimination half-life and gastric irritation as side effects. OBJECTIVE: The aim of the current investigation is to formulate and optimize a topical BDH ethosomal gel for weight gain control. MATERIALS AND METHODS: Box-Behnken design was applied to study the effect of independent variables: phosphatidylcholine (PC), propylene glycol (PG), and ethanol on vesicle size; entrapment efficiency; % drug release; and flux. The morphology and zeta potential of the optimized formulation were evaluated. The % drug release, flux, and pharmacodynamics of the optimized formulation gel were studied. RESULTS: The size and entrapment efficiency percent had a direct positive relationship with the concentration of PC and negative relationship with ethanol and PG. The % drug release and flux decreased with increasing PC and PG, while ethanol enhanced both responses. Regression modeling indicated a good correlation between dependent and independent variables, where F16 was chosen as the optimized formulation. F16 showed well-defined spherical vesicles and zeta potential of -24 mV, and % release from the gel exceeded 99.5% over 16 h with the flux of 0.28 mg/cm2/h. Food intake and weight gain of rats were significantly decreased after transdermal application of the BDH ethosomal gel when compared with control, placebo, and BDH gel. The histopathological findings proved the absence of inflammation and decrease in adipose tissue. CONCLUSION: Results obtained showed a significant, sustained transdermal absorption of BDH ethosomal gel and, consequently, a decrease in food intake and weight gain.

Loratadine bioavailability via buccal transferosomal gel: formulation, statistical optimization, in vitro/in vivo characterization, and pharmacokinetics in human volunteers.

Loratadine (LTD) is an antihistaminic drug that suffers limited solubility, poor oral bioavailability (owing to extensive first-pass metabolism), and highly variable oral absorption. This study was undertaken to develop and statistically optimize transfersomal gel for transbuccal delivery of LTD. Transfersomes bearing LTD were prepared by conventional thin film hydration method and optimized using sequential Quality-by-Design approach that involved Placket-Burman design for screening followed by constrained simplex-centroid design for optimization of a Tween-80/Span-60/Span-80 mixture. The transferosomes were characterized for entrapment efficiency, particle size, and shape. Optimized transferosomes were incorporated in a mucoadhesive gel. The gel was characterized for rheology, ex vivo permeation across chicken pouch buccal mucosa, in vitro release, and mucoadhesion. Pharmacokinetic behavior of LTD formulations was investigated in healthy volunteers following administration of a single 10-mg dose. Optimal transferosomes characterized by submicron size (380 nm), spherical shape and adequate loading capacity (60%) were obtained by using quasi-equal ratio surfactant mixture. In terms of amount permeated, percentage released, and mucoadhesion time, the transferosomal gel proved superior to control, transferosome-free gel. Bioavailability of the transferosomal gel was comparable to Claritin® oral tablets. However, inter-individual variability in Cmax and AUC was reduced by 76 and 90%, respectively, when the buccal gel was used. Linear Correlation of in vitro release with in vivo buccal absorption fractions was established with excellent correlation coefficient (R2>0.97). In summary, a novel buccal delivery system for LTD was developed. However, further clinical investigation is warranted to evaluate its therapeutic effectiveness and utility.

Development of a nanogel formulation for transdermal delivery of tenoxicam: a pharmacokinetic-pharmacodynamic modeling approach for quantitative prediction of skin absorption.

This study investigates potentials of solid lipid nanoparticles (SLN)-based gel for transdermal delivery of tenoxicam (TNX) and describes a pharmacokinetic-pharmacodynamic (PK-PD) modeling approach for predicting concentration-time profile in skin. A 23 factorial design was adopted to study the effect of formulation factors on SLN properties and determine the optimal formulation. SLN-gel tolerability was investigated using rabbit skin irritation test. Its anti-inflammatory activity was assessed by carrageenan-induced rat paw edema test. A published Hill model for in vitro inhibition of COX-2 enzyme was fitted to edema inhibition data. Concentration in skin was represented as a linear spline function and coefficients were estimated using non-linear regression. Uncertainty in predicted concentrations was assessed using Monte Carlo simulations. The optimized SLN was spherical vesicles (58.1 ± 3.1 nm) with adequate entrapment efficiency (69.6 ± 2.6%). The SLN-gel formulation was well-tolerated. It increased TNX activity and skin level by 40 ± 13.5, and 227 ± 116%, respectively. Average Cmax and AUC0-24 predicted by the model were 2- and 3.6-folds higher than the corresponding values computed using in vitro permeability data. SLN-gel is a safe and efficient carrier for TNX across skin in the treatment of inflammatory disorders. PK-PD modeling is a promising approach for indirect quantitation of skin deposition from PD activity data.

Development, Optimization, and Evaluation of Carvedilol-Loaded Solid Lipid Nanoparticles for Intranasal Drug Delivery.

Carvedilol, a beta-adrenergic blocker, suffers from poor systemic availability (25%) due to first-pass metabolism. The aim of this work was to improve carvedilol bioavailability through developing carvedilol-loaded solid lipid nanoparticles (SLNs) for nasal administration. SLNs were prepared by emulsion/solvent evaporation method. A 23 factorial design was employed with lipid type (Compritol or Precirol), surfactant (1 or 2% w/v poloxamer 188), and co-surfactant (0.25 or 0.5% w/v lecithin) concentrations as independent variables, while entrapment efficiency (EE%), particle size, and amount of carvedilol permeated/unit area in 24 h (Q 24) were the dependent variables. Regression analysis was performed to identify the optimum formulation conditions. The in vivo behavior was evaluated in rabbits comparing the bioavailability of carvedilol after intravenous, nasal, and oral administration. The results revealed high drug EE% ranging from 68 to 87.62%. Carvedilol-loaded SLNs showed a spherical shape with an enriched core drug loading pattern having a particle size in the range of 66 to 352 nm. The developed SLNs exhibited significant high amounts of carvedilol permeated through the nasal mucosa as confirmed by confocal laser scanning microscopy. The in vivo pharmacokinetic study revealed that the absolute bioavailability of the optimized intranasal SLNs (50.63%) was significantly higher than oral carvedilol formulation (24.11%). Hence, we conclude that our developed SLNs represent a promising carrier for the nasal delivery of carvedilol.

Nanotransfersomes of carvedilol for intranasal delivery: formulation, characterization and in vivo evaluation.

CONTEXT: Development of carvedilol-loaded transfersomes for intranasal administration to overcome poor nasal permeability and hepatic first pass effect so as to enhance its bioavailability. OBJECTIVE: The purpose of this study was to develop carvedilol-loaded transfersomes containing different edge activators (EAs) then evaluating the in vivo behavior of the optimized formula in rabbits. METHODS: The vesicles were prepared by incorporating different EAs including Span 20, Span 60, Tween 20, Tween 80, and sodium deoxycholate (SDC) in the lipid bilayer and each EA was used in three different ratios with respect to phosphatidylcholine (PC) including 95:5%, 85:15%, and 75:25% w/w (PC:EA). Evaluation of transfersomes was carried out in terms of shape, size, entrapment efficiency (EE), in vitro release, ex vivo permeation, confocal laser scanning microscopy (CLSM), and stability studies. The pharmacokinetic study of the optimized formula was conducted in rabbits. RESULTS: The mean diameter of the vesicles was in the range of 295-443 nm. Transfersomes prepared with 95:5% (w/w) (PC:EA) ratio showed highest EE% where Span 60 gave the highest values. Whereas those prepared using 85:15% w/w ratio showed highest percentages of drug release where SDC was superior to other EAs. The developed transfersomes exhibited significantly higher amounts of carvedilol permeated through nasal mucosa. CLSM of formula T14 containing SDC with 85:15% (w/w) (PC:EA) ratio revealed high permeation across the nasal mucosa. CONCLUSION: The nanotransfersomal vesicles were significantly more efficient in nasal delivery of carvedilol with absolute bioavailability of 63.4%.

Formulation and evaluation of meloxicam niosomes as vesicular carriers for enhanced skin delivery.

CONTEXT: Skin delivery of Meloxicam (MX) offers several advantages over the oral route which is associated with potential side effects. OBJECTIVES: The aim of this study was to develop transdermal MX in niosomes. MATERIALS AND METHODS: Vesicles prepared by thin film hydration method were characterized and the acute anti-inflammatory activity of 0.5% MX niosomal hydrogel was evaluated using carrageenan induced rat paw edema method. RESULTS: The results revealed that niosomes prepared from span 60 and cholesterol at 6:4 molar ratio using 20 mg of MX were of the highest entrapment efficiency (> 55%) and with particle size (187.3 nm). There was a marked increase in the percentage inhibition of edema in animals treated with MX vesicular gel compared to those treated with free MX and piroxicam gels. DISCUSSION: There was an inverse proportionality between vesicle size and cholesterol content. With increased cholesterol molar ratio the bilayer stability increased and permeability decreased leading to efficiently trapping the MX. In contrast, higher amounts of cholesterol may compete with the drug for packing space within the bilayer. The inhibitory effect of MX niosomal gel may be attributed to its superior skin permeation. CONCLUSIONS: The results suggest that niosomes may be promising vehicles for transdermal delivery of MX.