Formulation and optimization of clotrimazole-loaded proniosomal gel using 3(2) factorial design

Ferrous ascorbate non-effervescent floating mini-caplets as an oral iron supplement

PURPOSE

This research aimed to develop non-effervescent floating mini-caplets of Ferrous Ascorbate (FA) using low-density polymers to overcome the problems of poor bioavailability associated with immediate-release iron products. Methods: The excipients and method (melt granulation) were selected based on pre-and post-compression parameters in trial batches. The formulation was optimized by a full factorial 32 experimental design. An optimized formulation was evaluated for drug release kinetic, accelerated stability study, and in vivo study in healthy adult New Zealand female rabbits. Results: The optimized formulation F6 mini-caplets (42.5% FA, 45% Glyceryl palmitostearate as Precirol, 10% polyvinyl pyrrolidone K-30, and 2.5% lactose) were found to have instant floating and 12 h floating duration in 0.1N Hydrochloric acid (HCl) dissolution medium. In vitro drug release (diffusion mechanism) at 1 h and 5 h was 30-35% and 65-70%, respectively. It was found stable for three months under an accelerated stability study. In vivo study showed significantly increased serum iron levels and decreased unsaturated iron binding capacity (UIBC) in the test group (optimized formulation) compared to control and standard (immediate-release iron). Conclusion: Based on the in vitro and in vivo results, we conclude that non-effervescent floating FA mini-caplets have higher bioavailability compared to immediate release FA, which may be attributed to prolonged iron release at its absorption site due to their retention in the gastric region. Hence, non-effervescent floating FA mini-caplets may act as a potential approach for iron deficiency.

Optimization of hyaluronan-enriched cubosomes for bromfenac delivery enhancing corneal permeation: characterization, ex vivo, and in vivo evaluation

To design and evaluate hyaluronan-based cubosomes loaded with bromfenac sodium (BS) for ocular application to enhance the corneal permeation and retention in pterygium and cataract treatment. BS-loaded cubosomes were prepared by the emulsification method, employing 2³ full factorial design using Design-Expert® software. Glycerol monoolein (GMO) and poloxamer 407 (P407) as lipid phase and polyvinyl alcohol (PVA) as stabilizer were the used ingredients. The optimized formulation (OBC; containing GMO (7% w/w), P407 (0.7% w/w) and PVA (2.5% w/w)) was further evaluated. OBC had an entrapment efficiency of 61.66 ± 1.01%, a zeta potential of -30.80 ± 0.61 mV, a mean particle size of 149.30 ± 15.24 nm and a polydispersity index of 0.21 ± 0.02. Transmission electron microscopy confirmed its cubic shape and excellent dispersibility. OBC exhibited high stability and no ocular irritation that was ensured by histopathology. Ex vivo permeation study showed a significant increase in drug deposition and permeability parameters through goat cornea, besides, confocal laser microscopy established the superior permeation capability of OBC, as compared to drug solution. In vivo pharmacokinetics in aqueous humor indicated higher AUC_0-tlast (18.88 µg.h/mL) and mean residence time (3.16 h) of OBC when compared to the marketed eye drops (7.93 µg.h/mL and 1.97 h, respectively). Accordingly, hyaluronan-enriched cubosomes can be regarded as a promising carrier for safe and effective topical ocular delivery.

Formulation of novel niosomal repaglinide chewable tablets using coprocessed excipients: in vitro characterization, optimization and enhanced hypoglycemic activity in rats

Repaglinide (RPG), a monotherapy insulin secretagogue used to treat diabetes mellitus-type II yet, it suffers from poor water solubility and variable bioavailability (∼ 50%) due to hepatic first pass metabolism. In this study, 2FI I-Optimal statistical design was employed to encapsulate RPG into niosomal formulations using cholesterol,span 60 and peceol^TM. The optimized niosomal formulation (ONF) showed particle size 306.60 ± 84.00 nm, zeta potential -38.60 ± 1.20 mV, polydispersity index 0.48 ± 0.05 and entrapment efficiency 92.00 ± 2.60%. ONF showed > 65% RPG release that lasted for 3.5 h, and significantly higher sustained release compared to Novonorm® tablets after 6 h (p < 0.0001). TEM for ONF showed spherical vesicles with dark core and light-colored lipid bilayer membrane. RPG peaks disappeared in FTIR confirming successful RPG entrapment. To eliminate dysphagia associating conventional oral tablets, chewable tablets loaded with ONF were prepared using coprocessed excipients; Pharmaburst^® 500, F-melt^® and Prosolv^® ODT. Tablets showed friability <1%, hardness 3.9 ± 0.423-4.7 ± 0.410 Kg, thickness 4.1 ± 0.045-4.4 ± 0.017 mm and acceptable weight.All tablets showed robust RPG release at 30 min compared to Novonorm^® tablets. At 6h, chewable tablets containing only Pharmaburst^® 500 and F-melt^® showed sustained and significantly increased RPG release compared to Novonorm^® tablets (p < 0.05). Pharmaburst^® 500 and F-melt^® tablets showed rapid in vivo hypoglycemic effect with 5 and 3.5 fold significant reduction in blood glucose compared to Novonorm^® tablets (p < 0.05) at 30 min. Also, at 6h the same tablets showed 1.5 and 1.3 fold significant extended reduction in blood glucose compared to the same market product (p < 0.05). It could be concluded that chewable tablets loaded with RPG ONF represent promising novel oral drug delivery systems for diabetic patients suffering from dysphagia.

Design development and optimisation of multifunctional Doxorubicin-loaded Indocynanine Green proniosomal gel derived niosomes for tumour management

This study presents the design, development, and optimization of multifunctional Doxorubicin (Dox)-loaded Indocyanine Green (ICG) proniosomal gel-derived niosomes, using Design of Experiments (2³ factorial model). Herein, the multifunctional proniosomal gel was prepared using the coacervation phase separation technique, which on hydration forms niosomes. The effect of formulation variables on various responses including Zeta potential, Vesicle size, entrapment efficiency of Dox, entrapment efficiency of ICG, Invitro drug release at 72nd hour, and NIR hyperthermia temperature were studied using statistical models. On the basis of the high desirability factor, optimized formulation variables were identified and validated with the experimental results. Further, the chemical nature, vesicle morphology, surface charge, and vesicle size of optimized proniosomal gel-derived niosomes were evaluated. In addition, the effect of free ICG and bound ICG on NIR hyperthermia efficiency has been investigated to demonstrate the heating rate and stability of ICG in the aqueous environment and increased temperature conditions. The drug release and kinetic studies revealed a controlled biphasic release profile with complex mechanisms of drug transport for optimized proniosomal gel-derived niosomes. The potential cytotoxic effect of the optimised formulation was also demonstrated invitro using HeLa cell lines.

Brain Targeting of Citicoline Sodium via Hyaluronic Acid-Decorated Novel Nano-Transbilosomes for Mitigation of Alzheimer's Disease in a Rat Model: Formulation, Optimization, in vitro and in vivo Assessment

BACKGROUND

Alzheimer's disease (AD) is one of the furthermost advanced neurodegenerative disorders resulting in cognitive and behavioral impairment. Citicoline sodium (CIT) boosts the brain's secretion of acetylcholine, which aids in membrane regeneration and repair. However, it suffers from poor blood-brain barrier (BBB) permeation, which results in lower levels of CIT in the brain.

PURPOSE

This study targeted to encapsulate CIT into novel nano-platform transbilosomes decorated with hyaluronic acid CIT-HA*TBLs to achieve enhanced drug delivery from the nose to the brain.

METHODS

A method of thin-film hydration was utilized to prepare different formulae of CIT-TBLs using the Box-Behnken design. The optimized formula was then hyuloranated via integration of HA to form the CIT-HA*TBLs formula. Furthermore, AD induction was performed by aluminum chloride (Alcl3), animals were allocated, and brain hippocampus tissue was isolated for ELISA and qRT-PCR analysis of malondialdehyde (MDA), nuclear factor kappa B (NF-kB), and microRNA-137 (miR-137) coupled with immunohistochemical amyloid-beta (Aβ1-42) expression and histopathological finding.

RESULTS

The hyuloranated CIT-HA*TBLs formula, which contained the following ingredients: PL (300 mg), Sp 60 (43.97 mg), and SDC (20 mg). They produced spherical droplets at the nanoscale (178.94 ±12.4 nm), had a high entrapment efficiency with 74.92± 5.54%, had a sustained release profile of CIT with 81.27 ±3.8% release, and had ex vivo permeation of CIT with 512.43±19.58 μg/cm2. In vivo tests showed that CIT-HA*TBL thermogel dramatically reduces the hippocampus expression of miR-137 and (Aβ1-42) expression, boosting cholinergic neurotransmission and decreasing MDA and NF-kB production. Furthermore, CIT-HA*TBLs thermogel mitigate histopathological damage in compared to the other groups.

CONCLUSION

Succinctly, the innovative loading of CIT-HA*TBLs thermogel is a prospectively invaluable intranasal drug delivery system that can raise the efficacy of CIT in Alzheimer's management.

Niosomal formulation of hydroxytyrosol, a polyphenolic antioxidant, for enhancing transdermal delivery across human cadaver skin

Hydroxytyrosol (HT), a naturally occurring polyphenol from the olive plant, is a potent antioxidant, cardioprotective, neuroprotective, and anti-inflammatory agent. Upon oral administration, HT undergoes rapid elimination within minutes and thus limiting its therapeutic utility. Due to its hydrophilic nature, percutaneous absorption and transdermal delivery of HT are very low. The aim of this research was to enhance the skin permeation of hydroxytyrosol using a niosome gel formulation. The formulations prepared with Span 60 as surfactant showed uniform particle size and high encapsulation efficiency (>90%). The niosome formulations showed a pseudoplastic behavior for topical application within the lipid/surfactant composition of 45-50%. The formulations showed a controlled release of HT compared to the HT solution. The flux of HT across human skin was increased by 28 and 4.4 fold compared to aqueous and ethanolic HT solutions, respectively (p < 0.001). The presence of lecithin lowered the flux and increased the retention of the formulations compared to HT solutions (p < 0.001). The formulations containing lecithin showed two-fold higher skin retention of hydroxytyrosol (p < 0.05). In conclusion, this study demonstrates niosome gel as a promising alternative to oral delivery of HT, providing sustained delivery and greater efficacy.

Intranasal Zolmitriptan-Loaded Bilosomes with Extended Nasal Mucociliary Transit Time for Direct Nose to Brain Delivery

This study aimed at delivering intranasal zolmitriptan directly to the brain through preparation of bilosomes incorporated into a mucoadhesive in situ gel with extended nasal mucociliary transit time. Zolmitriptan-loaded bilosomes were constructed through a thin film hydration method applying Box-Behnken design. The independent variables were amount of sodium deoxycholate and the amount and molar ratio of cholesterol/Span® 40 mixture. Bilosomes were assessed for their entrapment efficiency, particle size and in vitro release. The optimal bilosomes were loaded into mucoadhesive in situ gel consisting of poloxamer 407 and hydroxypropyl methylcellulose. The systemic and brain kinetics of Zolmitriptan were evaluated in rats by comparing intranasal administration of prepared gel to an IV solution. Statistical analysis suggested an optimized bilosomal formulation composition of sodium deoxycholate (5 mg) with an amount and molar ratio of cholesterol/Span® 40 mixture of 255 mg and 1:7.7, respectively. The mucoadhesive in situ gel containing bilosomal formulation had a sol-gel temperature of 34.03 °C and an extended mucociliary transit time of 22.36 min. The gelling system possessed enhanced brain bioavailability compared to bilosomal dispersion (1176.98 vs. 835.77%, respectively) following intranasal administration. The gel revealed successful brain targeting with improved drug targeting efficiency and direct transport percentage indices. The intranasal delivery of mucoadhesive in situ gel containing zolmitriptan-loaded bilosomes offered direct nose-to-brain drug targeting with enhanced brain bioavailability.

Formulation and Characterization of Acetazolamide/Carvedilol Niosomal Gel for Glaucoma Treatment: In Vitro, and In Vivo Study

Acetazolamide (ACZ) is a diuretic used in glaucoma treatment; it has many side effects. Carvedilol (CAR) is a non-cardioselective beta-blocker used in the treatment of elevated intraocular pressure; it is subjected to the first-pass metabolism and causes fluids accumulation leading to edema. This study focuses on overcoming previous side effects by using a topical formula of a combination of the two previous drugs. Sixty formulations of niosomes containing Span 20, Span 60, Tween 20, and Tween 60 with two different ratios were prepared and characterized. Formulation with the lowest particle size (416.30 ± 0.23), the highest zeta potential (72.04 ± 0.43 mv), and the highest apparent coefficient of corneal permeability (0.02 ± 0.29 cm/h) were selected. The selected formula was incorporated into the gel using factorial design 2³. Niosomes (acetazolamide/carvedilol) consisting of Span 60 and cholesterol in the molar ratio (7:6), HMPC, and carbopol with two different ratios were used. The selected formula was subjected to an in vivo study of intraocular pressure in ocular hypertensive rabbits for 60 h. The sustained gel formula of the combination decreased (IOP) to normal after 1 h and sustained efficacy for 4 days. Histological analysis of rabbit eyeballs treated with the selected formula showed improvement in glaucomatous eye retinal atrophy.

Cubogel as potential platform for glaucoma management

The aim of this work is to survey the potential of cubogel as an ocular dosage form to boost the corneal permeability of Dorzolamide Hydrochloride DZ; an antiglaucomal drug. DZ-loaded cubosomal dispersions were prepared according to Box-Behnken design, where the effect of independent variables; Monoolein MO concentration (2.5, 5 and 7.5%w/w), Pluronic^® F127 concentration (0.25, 0.5 and 0.75%w/w) and magnetic stirrer speed of (400, 800 and 1200 rpm) was studied on PS (nm), Zp (−mV) and Q 2 h (%) respectively. The prepared formulae were characterized via drug content DC (%), particle size PS (nm), polydispersity index PDI, zeta potential Zp (−mV), in-vitro drug release (Q 2 h%) and finally TEM. The optimized formulation composed of: 6.13% w/w of MO, 0.75% w/w of F127 and prepared at 1200 rpm stirring speed was chosen based on the criteria of minimum PS (nm), maximum Zp (−mV) and minimum Q 2 h (%). Results revealed that the optimum formula showed PS of 153.3 ± 8.4 n, Zp of 32 ± 3 −mV and 37.78 ± 1.3% released after 2 h. Carbopol 934 (1% w/v) as gelling agent was used to prepare the optimum cubogel, which was further evaluated by DSC, ex-vivo permeation and stability studies at 4 °C for three months. Moreover, in vivo studies of the optimized cubogel include; draize test, histological examination, confocal laser scanning microscopy (CLSM) and intraocular pressure (IOP) measurement. Results revealed that the optimized cubogel was considerably safe, stable and competent to corneal delivery as assured by draize and histological examination. CLSM showed a deeper penetration of more than 2.5-fold. A higher bioavailability (288.24 mg. h/ml) was attained from cubogel compared to the market product Trusopt^® eye drops (115.40 mg. h/ml) following IOP measurement. Therefore, DZ-loaded cubogel could be considered as promising delivery system to boost the transcorneal permeation hence corneal bioavailability of DZ as antiglaucomal drug.

Proniosomal Gel for Topical Delivery of Rutin: Preparation, Physicochemical Characterization and In Vitro Toxicological Profile Using 3D Reconstructed Human Epidermis Tissue and 2D Cells

Rutin (Rut) is a natural flavonol, well-known for its broad-spectrum of therapeutic effects, including antioxidant and antitumoral activities; still, it has a reduced clinical outcome due to its limited solubility in aqueous solutions. To overcome this drawback, this study proposes a novel formulation for rutin as a proniosomal gel for cutaneous applications. The gel was prepared by coacervation phase-separation method and complies with the standard requirements in terms of particle size (140.5 ± 2.56 nm), zeta potential (−27.33 ± 0.09 mV), encapsulation capacity (> 50%), pH (7.002 ± 0.18) and rheological properties. The results showed high biocompatibility of the gel on the 3D reconstructed human epidermis model characterized by increased viability of the cells and a lack of irritant and phototoxic potential. The evaluations on 2D cells confirm the preferential cytotoxic effect of Rut on melanoma cells (IC₅₀ value = 8.601 µM, nuclear fragmentation) compared to normal keratinocytes. Our data suggest that the proniosomal gel is a promising drug carrier for Rut in the management and prevention of skin disorders.

Fabrication of Transgelosomes for Enhancing the Ocular Delivery of Acetazolamide: Statistical Optimization, In Vitro Characterization, and In Vivo Study

Acetazolamide (ACZ) is a potent carbonic anhydrase inhibitor that is used for the treatment of glaucoma. Its oral administration causes various undesirable side effects. This study aimed to formulate transgelosomes (TGS) for enhancing the ocular delivery of ACZ. ACZ-loaded transfersomes were formulated by the ethanol injection method, using phosphatidylcholine (PC) and different edge activators, including Tween 80, Span 60, and Cremophor RH 40. The effects of the ratio of lipid to surfactant and type of surfactant on % drug released after 8 h (Q_8h) and entrapment efficiency (EE%) were investigated by using Design-Expert software. The optimized formula was formulated as TGS, using poloxamers as gelling agents. In vitro and in vivo characterization of ACZ-loaded TGS was performed. According to optimization study, F8 had the highest desirability value and was chosen as the optimized formula for preparing TGS. F8 appeared as spherical elastic nanovesicles with Q_8h of 93.01 ± 3.76% and EE% of 84.44 ± 2.82. Compared to a free drug, TGS exhibited more prolonged drug release of 71.28 ± 0.46% after 8 h, higher ex vivo permeation of 66.82 ± 1.11% after 8 h and a significant lowering of intraocular pressure (IOP) for 24 h. Therefore, TGS provided a promising technique for improving the corneal delivery of ACZ.

Proniosomal gel-derived niosomes: an approach to sustain and improve the ocular delivery of brimonidine tartrate; formulation, in-vitro characterization, and in-vivo pharmacodynamic study

Brimonidine tartrate (BRT) is a hydrophilic α2 adrenergic agonist used for the treatment of glaucoma. Glaucoma is an ocular disease affecting the anterior segment of the eye requiring lifetime treatment. Owing to the obstacles facing ocular delivery systems and hydrophilicity of BRT, frequent administration of the eye drops is required. Niosomes have been widely used to improve the ocular bioavailability of the topically applied drugs and to enhance the ocular residence time. However, they have drawbacks as physical instability, aggregation, and loss of the entrapped drug. For this reason, BRT proniosomes were prepared to overcome niosomal instability issues. A D-optimal design was utilized to determine the optimum conditions for preparation of the proniosomal gels. Independent variables were amount of surfactant, surfactant:cholesterol ratio, and type of surfactant used. The dependent variables were entrapment efficiency (EE%), particle size, percentage of drug released after 2 h (Q2h), and percentage of drug released after 24 h (Q24h). The optimum formula was suggested with desirability 0.732 and the composition of 540 mg Span 60 and 10:1 surfactant:cholesterol ratio. The results obtained after reconstitution were; EE% of 79.23 ± 1.12% particle size of 810.95 ± 16.758 nm, polydispersity index (PDI) 0.6785 ± 0.213, zeta potential 59.1 ± 0.99 mV, Q2h40.98 ± 1.29%, Q8h 63.35 ± 6.07%, and Q24h = 91.11 ± 1.76%. Transmission electron microscope imaging of the formula showed the typical spherical shape of niosomes. In-vivo pharmacodynamic study assured the improved ocular bioavailability of BRT selected formula when compared with Alphagan®P with relative AUC0-24 of 5.024 and 7.90 folds increase in the mean residence time (MRT). Lack of ocular irritation of the formula was assured by Draize test.

Development and Evaluation of Optimized Thiolated Chitosan Proniosomal Gel Containing Duloxetine for Intranasal Delivery

Proniosomes offer excellent potential for improved drug delivery, through versatile routes, by overcoming the permeation barriers faced by several drugs. The study was aimed to develop a thiomer gel containing duloxetine proniosomes for the intranasal delivery, improving its bioavailability and brain delivery through olfactory system. Duloxetine-loaded proniosomes were optimized through Design-Expert Software, prepared by coacervation phase separation method and then characterized in vitro for different vesicle features, and permeation enhancement potential using various techniques. The formulation F2, out of all the trials, fulfilled the maximum requisite of highest entrapment efficiency (76.21 ± 1.24%) and minimum vesicle size (223.91 ± 11.07 nm). The F2 was embedded in thiolated chitosan gel rendering it mucoadhesive and further characterized. The in vitro release showed a sustained drug release from the mucoadhesive proniosomal gel with only 54% drug release as compared to that of 71% from proniosome over 8 h, following Higuchi drug release model. Ex vivo permeation studies showed the enhancement ratio for the mucoadhesive proniosomal gel to be 1.86-fold greater than proniosomes, indicating a significant improvement in transmucosal permeation. The results suggest that incorporation of proniosomes into thiolated gel can significantly improve its mucoadhesion and retention time in the nasal cavity for providing a sustained drug release. Thus, gel formulation could be considered as a promising approach for efficient intranasal drug delivery of duloxetine. Graphical Abstract.

Bilosomes as a novel carrier for the cutaneous delivery for dapsone as a potential treatment of acne: preparation, characterization and in vivo skin deposition assay

In our study, the potential of bilosomes as novel vesicular carrier for the cutaneous delivery of the sulphone compound, Dapsone, for topical treatment of acne was investigated. The effect of different formulation variables (type and concentration of bile salt, and molar ratio of Span 60:cholesterol) on the properties of DPS-loaded bilosomes was investigated using a full factorial design. Design Expert software was used for data analysis and optimization of DPS-loaded bilosomes. The optimized bilosomes, chosen on the basis of their superior properties giving maximum entrapment, in vitro release after different time intervals and RE% with minimum vesicle size. Results showed that the bilosome system prepared using Span^® 60: Cholesterol (5:1) and containing 0.25 M sodium deoxycholate as the bile salt was found to obey these criteria, with a desirability value of 0.637. Therefore, this system was chosen for further assessment for its morphological properties, zeta potential, thermal analysis using differential scanning calorimetry and X-ray diffractometry. Results revealed that the chosen bilosomes were spherical in shape with no aggregation, and contained DPS in a molecularly dispersed amorphous form. Finally, the capability of the optimized DPS-loaded bilosomes to deliver DPS through rat skin layers will be investigated and compared with that of DPS alcoholic solution. Results showed that the amounts of DPS retained in the skin treated with DPS-loaded bilosomes, and DPS alcoholic solution after 24 h were found to be 170.57 ± 55.12 and 120.24 ± 10.7 µg/mL, respectively, representing about 1.5-fold higher drug retained in the bilosomes-treated skin. Finally, the safety and the tolerability of the prepared bilosomes were assessed using histopathological examination, and revealed that the control untreated skin sections and skin sections treated with DPS-loaded bilosomes showed normal histological structures characterized by absence of defects or inflammation. Such results can be considered a good addition in the field of pharmaceutical drug delivery for effective topical therapy of acne.

Sustained ocular delivery of Dorzolamide-HCl via proniosomal gel formulation: in-vitro characterization, statistical optimization, and in-vivo pharmacodynamic evaluation in rabbits

Glaucoma is the second cause of blindness worldwide. Frequent administration of traditional topical dosage forms may lead to patient incompliance and failure of treatment. Our study aims to formulate proniosomal gel formulations that sustain the release of the water-soluble anti-glaucoma drug Dorzolamide-HCl (Dorz). Proniosomal gel formulations were prepared using coacervation phase separation method according to a 5² full factorial design. The effects of Cholesterol and surfactant (Span 40) amounts (independent variables) on the percentage entrapment efficiency (EE%), particle size (PS), and the percent of drug released after 8 h (Q8h) (dependent variables (DVs)) were investigated. An optimized formulation (OF) was chosen based on maximizing EE% and Q8h and minimizing PS. An intraocular pressure (IOP) pharmacodynamic study was performed in rabbits to evaluate the in-vivo performance of the OF-gel compared to the marketed Trusopt^® eye drops. The results showed that the independent variables studied significantly affected EE%, PS, and Q8h. OF was the one containing 60 mg Cholesterol and 540 mg Span 40. It had desirability of 0.885 and its actually measured DVs deviated from the predicted ones by a maximum of 4.8%. The in-vivo pharmacodynamic study showed that OF could result in higher reduction in IOP, significantly sustain that reduction in IOP and increase Dorz bioavailability compared to Trusopt^® eye drops. Thus the OF-gel is very promising for being used in glaucoma treatment.

Transdermal delivery of oxybutynin chloride proniosomal gels for the treatment of overactive bladder

CONTEXT

Overactive bladder (OAB) is a common problem and anticholinergic drugs are first-line therapy, but they have side effects.

OBJECTIVE

Development of oxybutynin chloride (OC) proniosomal gels and analyses of its efficacy for OAB treatment.

MATERIALS AND METHODS

Phase separation coacervation was used to prepare proniosomal gels using various non-ionic surfactants, lipids, soy lecithin and isopropyl alcohol. Gels were characterized with regard to entrapment efficiency (EE), vesicle size, surface morphology (using environmental scanning electron microscopy [E-SEM]), stability, attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, in vitro skin permeation, in vivo animal studies and histopathology.

RESULTS AND DISCUSSION

EE was 87-92%, vesicle size was 0.38-5.0 μm, and morphology showed some loosened pores in proniosomes after hydration. ATR-FTIR spectroscopy showed no significant shifts in peaks corresponding to OC and excipients. Most formulations exhibited >50% permeation but the cholesterol-containing formulations P3 (Span 20:Span 60 [1:1]) and P4 [Tween 20:Tween 80 (1:1)] had the highest percent cumulative permeation. P3 and P4 also showed faster recovery of cholinergic effects on salivary glands than oral formulations. P3 and P4 had pronounced therapeutic effects in reduction of urinary frequency and demonstrated improvements in bladder morphology (highly regenerative surface of the transitional epithelium).

CONCLUSION

These results suggest that OC could be incorporated into proniosomal gels for transdermal delivery in the treatment of OAB.