Enhanced topical delivery of terbinafine hydrochloride with chitosan hydrogels

Nanotechnology-based Drug Delivery of Topical Antifungal Agents

Among the various prominent fungal infections, superficial ones are widespread. A large number of antifungal agents and their formulations for topical use are commercially available. They have some pharmacokinetic limitations which cannot be retracted by conventional delivery systems. While nanoformulations composed of lipidic and polymeric nanoparticles have the potential to overcome the limitations of conventional systems. The broad spectrum category of antifungals i.e. azoles (ketoconazole, voriconazole, econazole, miconazole, etc.) nanoparticles have been designed, prepared and their pharmacokinetic and pharmacodynamic profile was established. This review briefly elaborates on the types of nano-based topical drug delivery systems and portrays their advantages for researchers in the related field to benefit the available antifungal therapeutics.

Superficial Dermatophytosis across the World's Populations: Potential Benefits from Nanocarrier-Based Therapies and Rising Challenges

The most prevalent infection in the world is dermatophytosis, which is a major issue with high recurrence and can affect the entire body including the skin, hair, and nails. The major goal of this Review is to acquire knowledge about cutting-edge approaches for treating dermatophytosis efficiently by adding antifungals to formulations based on nanocarriers in order to overcome the shortcomings of standard treatment methods. Updates on nanosystems and research developments on animal and clinical investigations are also presented. Along with the currently licensed formulations, the investigation also emphasizes novel therapies and existing therapeutic alternatives that can be used to control dermatophytosis. The Review also summarizes recent developments on the prevalence, management approaches, and disadvantages of standard dosage types. There are a number of therapeutic strategies for the treatment of dermatophytosis that have good clinical cure rates but also drawbacks such as antifungal drug resistance and unfavorable side effects. To improve therapeutic activity and get around the drawbacks of the traditional therapy approaches for dermatophytosis, efforts have been described in recent years to combine several antifungal drugs into new carriers. These formulations have been successful in providing improved antifungal activity, longer drug retention, improved effectiveness, higher skin penetration, and sustained drug release.

Hydrogel Formulations for Topical Insulin Application: Preparation, Characterization and In Vitro Permeation across the Strat-M® Membrane

Insulin has shown efficacy in the treatment of hard-to-heal wounds, which is mainly due to its role in regulating oxidative stress and inflammatory reactions. The aim of this study was to develop an insulin-hydrogel carrier based on Sepineo™ P 600 and Sepineo™ PHD 100 for application to lesional skin. Preformulation studies of the developed formulations were performed in terms of analysis of the pharmaceutical availability of insulin from the hydrogels through the Strat-M® membrane, and rheological and texture measurements. Insulin is released in a prolonged manner; after a time of 6.5 h, 4.01 IU/cm2 (53.36%) and 3.69 IU/cm2 (47.4%) of the hormone were released from the hydrogel based on Sepineo™ P 600 and Sepineo™ PHD 100, respectively. Rheological analysis showed that the hydrogels tested belong to non-Newtonian, shear-thinning systems with yield stress. The insulin-hydrogel based on Sepineo™ P 600 and Sepineo™ PHD 100 shows optimal application properties. The results obtained provide a basis for further preclinical and clinical studies.

The Expanded Role of Chitosan in Localized Antimicrobial Therapy

Chitosan is one of the most studied natural origin polymers for biomedical applications. This review focuses on the potential of chitosan in localized antimicrobial therapy to address the challenges of current rising antimicrobial resistance. Due to its mucoadhesiveness, chitosan offers the opportunity to prolong the formulation residence time at mucosal sites; its wound healing properties open possibilities to utilize chitosan as wound dressings with multitargeted activities and more. We provide an unbiased overview of the state-of-the-art chitosan-based delivery systems categorized by the administration site, addressing the site-related challenges and evaluating the representative formulations. Specifically, we offer an in-depth analysis of the current challenges of the chitosan-based novel delivery systems for skin and vaginal infections, including its formulations optimizations and limitations. A brief overview of chitosan's potential in treating ocular, buccal and dental, and nasal infections is included. We close the review with remarks on toxicity issues and remaining challenges and perspectives.

Promising nanogels loaded with usnic acid for oral ulcer treatment: development, characterization, and in vivo evaluation in rabbits

This study aimed to present an effective formulation targeting oral ulcers that will remain in the application site for a longer period, reducing the frequency of administration. As a candidate formulation, usnic acid (UA) was loaded into the optimum nanogels. The characterization studies included physical, rheological, and bioadhesive properties as well as in vitro release and ex vivo studies. The rheological results revealed that the nanogels present pseudoplastic flow behavior. In vitro drug release showed a prolonged pattern. In further, the chosen UA nanogels showed very low percentages of penetration and permeation. F13, which showed the highest release, suitable bioadhesive properties (0.475 ± 0.033 N/cm²) and eligible particle size (250.22 ± 4.11 nm), PDI (0.089 ± 0.052), and zeta potential (20.56 ± 0.330 mV) values were chosen for in vivo experiments. The selected UA nanogels showed effective antimicrobial activity against Bacillus Cereus and great in vivo wound healing properties. The results indicated that suitable UA nanogels with desired properties could be prepared. The therapeutic potential of the nanogels for oral ulcers was assessed using an animal model and the histopathological findings suggested that the optimized formulation is a good choice for oral ulcer treatment. Nonetheless, further research is recommended to support its efficacy by applying pharmacodynamic and pharmacokinetic studies in human individuals.

Development and Evaluation of Polymeric Nanosponge Hydrogel for Terbinafine Hydrochloride: Statistical Optimization, In Vitro and In Vivo Studies

Terbinafine hydrochloride, although one of the prominent antifungal agents, suffers from low drug permeation owing to its hydrophobic nature. The approach of nanosponge formulation may thus help to resolve this concern. Thus, the present research was envisioned to fabricate the nanosponge hydrogel of terbinafine hydrochloride for topical delivery since nanosponge augments the skin retentivity of the drug. The optimized formulation was obtained using Box Behnken Design. The dependent and independent process parameters were also determined wherein polyvinyl alcohol (%), ethylcellulose (%), and tween 80 (%) were taken as independent process parameters and particle size, polydispersity index (PDI), and entrapment efficiency (EE) were the dependent parameters. The nanosponge was then incorporated into the hydrogel and characterized. In-vitro drug release from the hydrogel was 90.20 ± 0.1% which was higher than the drug suspension and marketed formulation. In vitro permeation potential of the developed formulation through rat skin showed a flux of 0.594 ± 0.22 µg/cm²/h while the permeability coefficient was 0.059 ± 0.022 cm/s. Nanosponge hydrogel was evaluated for non-irritancy and antifungal activity against C. albicans and T. rubrum confirming the substantial outcome. Tape stripping studies exhibited ten times stripping off the skin quantified 85.6 ± 0.21 μg/cm². The confocal analysis justified the permeation potential of the prepared hydrogel. The mean erythemal score was 0.0, confirming that the prepared hydrogel did not cause erythema or oedema. Therefore, based on results obtained, nanosponge hydrogel formulation is a potential carrier for efficient topical delivery of terbinafine hydrochloride.

Current Insights on Antifungal Therapy: Novel Nanotechnology Approaches for Drug Delivery Systems and New Drugs from Natural Sources

The high incidence of fungal infections has become a worrisome public health issue, having been aggravated by an increase in host predisposition factors. Despite all the drugs available on the market to treat these diseases, their efficiency is questionable, and their side effects cannot be neglected. Bearing that in mind, it is of upmost importance to synthetize new and innovative carriers for these medicines not only to fight emerging fungal infections but also to avert the increase in drug-resistant strains. Although it has revealed to be a difficult job, new nano-based drug delivery systems and even new cellular targets and compounds with antifungal potential are now being investigated. This article will provide a summary of the state-of-the-art strategies that have been studied in order to improve antifungal therapy and reduce adverse effects of conventional drugs. The bidirectional relationship between Mycology and Nanotechnology will be also explained. Furthermore, the article will focus on new compounds from the marine environment which have a proven antifungal potential and may act as platforms to discover drug-like characteristics, highlighting the challenges of the translation of these natural compounds into the clinical pipeline.

Tazarotene-loaded in situ gels for potential management of psoriasis: biocompatibility, anti-inflammatory and analgesic effect

Psoriasis is a chronic autoinflammatory disorder characterized by patches of abnormal skin. For psoriasis management, the application of topical retinoids as Tazarotene is recommended. However, Tazarotene could induce skin irritation limiting its use. Herein, it is evaluated the possible usage of in situ gels for tazarotene skin delivery. The topical in situ gels were developed using thermosensitive poloxamers via cold method. They were examined for their appearance, sol-gel temperature, clarity, pH, viscosity, in vitro release, and stability. Their biocompatibility was evaluated by investigating their cytotoxicity and irritation inducing capacity. The possible anti-inflammatory and analgesic activities were determined by measuring the nitric oxide and prostaglandin E₂ levels production in LPS-stimulated RAW264.7 murine macrophage cells. It was revealed that the in situ gels had no cytotoxic effect (∼95-100% cell viability) and nor irritation potential (∼97% cell viability), according to the in vitro EpiDerm™ reconstituted skin irritation test. Additionally, the 10% tazarotene-in situ gels showed possible analgesic activity since the production of prostaglandin E₂ (PGE₂) was decreased. In further, both concentrations of 5% and 10% tazarotene-in situ gels inhibited significantly the nitrite oxide production at 16% and 19%, respectively. Finally, the prepared in situ gels can act as a potential non-irritant alternative option for tazarotene topical skin delivery.

Mussel-Inspired Polydopamine Coating Enhances the Intracutaneous Drug Delivery from Nanostructured Lipid Carriers Dependently on a Follicular Pathway

Inspired by the structure and function of the mussel adhesive protein, a facile strategy involving oxidative polymerization of dopamine was proposed for surface modification of nanostructured lipid carriers (NLCs) to promote drug delivery in the skin. The formation of a polydopamine (PDA) layer rounding the surface of NLCs was confirmed by the X-ray photoelectron spectroscopy and the Fourier transform infrared spectroscopy studies. Using terbinafine (TBF) as a model drug, the in vitro permeation study revealed that the PDA coating significantly enhanced the delivery of TBF from NLCs to the deep skin layers, where the follicular pathway played an essential role as suggested by the hair follicle blocking and differential tape stripping experiments, as well as the laser scanning confocal microscopy study by using Nile red as the fluorescent probe. The cellular investigation indicated that the PDA coating led to a higher cellular uptake of nanoparticles in human immortalized keratinocytes (HaCaT) without causing additional cytotoxicity. Using endocytic inhibitors, it was found that the lipid raft/caveolae-mediated endocytosis was strongly involved in the internalization of both the PDA modified and unmodified NLCs. Our results suggested that surface modification of NLCs with PDA coating improved the intracutaneous drug delivery mainly via the follicular pathway, which provided an avenue for the development of potential drug delivery carriers for dermal use.

Lecithin Microemulsion Lipogels Versus Conventional Gels for Skin Targeting of Terconazole: In Vitro, Ex Vivo, and In Vivo Investigation

Topical treatment of fungal infections has several superiorities over oral treatment. However, the greatest challenge for dermal delivery is the stratum corneum which is considered an effective barrier for penetration of most antifungal drugs into deeper skin layers. Terconazole (Tr), which is the first marketed triazole antifungal, was reported to be one of the most active azoles against vaginal candidiasis. Nevertheless, our work group is the first to investigate the potential of Tr in the treatment of skin mycosis via integration into lecithin microemulsion-based lipogels (LMBGs). The microemulsion regions of the investigated systems were detected through ternary phase diagrams. The in vitro characterization studies revealed promising physicochemical merits for the selected LMBGs as well as satisfactory in vitro antifungal activity. The current research work was endeavored to investigate the potential of such novel Tr-loaded LMBGs in comparison with conventional gels. Ex vivo permeation and retention studies in addition to in vivo deposition study showed a significant improvement in the permeability of Tr through animal skin from LMBGs compared to other conventional gels. Furthermore, the optimized microemulsion lipogel proved to be safe and a nonirritant to experimental animals through the acute sensitivity study and histological skin examination. Overall, lecithin-based microemulsion lipogels of different composition confirmed their potential as interesting nanocarriers for skin delivery of terconazole compared to current therapy.

Terbinafine hydrochloride nail lacquer for the management of onychomycosis: formulation, characterization and in vitro evaluation

AIM

The present investigation's intention was to develop an optimized nail lacquer (NL) for the management of onychomycosis.

MATERIALS & METHODS

The NL was optimized statistically adopting 3² full factorial design having different polymer ratios and solvent ratios. The formulations were assessed for drug permeation drying time and peak adhesive strength of the film. Characterization was done using techniques including attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), x-ray diffraction (XRD), etc.

RESULTS & CONCLUSION

The formulation that had 1:1 polymer ratio and 80:20 solvent ratio was chosen as the optimized formulation. In vitro permeation studies showed better penetration (∼3.25-fold) as well as retention (∼11-fold) of the optimized NL formulation in the animal hoof as compared with the commercial formulation. The findings of in vitro and ex vivo studies elucidated the potential of the optimized formulation. [Formula: see text].

Nanoemulsion-Loaded Hydrogels for Topical Administration of Pentyl Gallate

The aim of this study is to describe the development of nanoemulsion-loaded hydrogels to deliver pentyl gallate (PG), a gallic acid n-alkyl ester, through the skin. PG is an antioxidant agent; however, it seems to be a promising agent for herpis labialis treatment. Aristoflex AVC^® and chitosan were used as gelling agents for nanoemulsion thickening. The developed formulations presented suitable PG content (94.4-100.3% w/w), nanometric droplet sizes (162-297 nm), high zeta potentials, and a non-Newtonian pseudoplastic behavior. Both vehicles neither enhanced PG penetration nor delayed its release from the nanoemulsion. Formulations remained physically stable at 8°C during 3 months of storage.

Trans-resveratrol-loaded nonionic lamellar liquid-crystalline systems: structural, rheological, mechanical, textural, and bioadhesive characterization and evaluation of in vivo anti-inflammatory activity

Resveratrol (Res) is a common phytoalexin present in a few edible materials, such as grape skin, peanuts, and red wine. Evidence has shown the beneficial effects of Res on human health, which may be attributed to its anti-inflammatory activity. However, the poor aqueous solubility of Res limits its therapeutic effectiveness. Therefore, the use of nanostructured delivery systems for Res, such as liquid-crystalline systems, could be beneficial. In this study, we aimed to develop, characterize, and determine the in vivo effectiveness of Res-loaded liquid-crystalline systems. Systems containing copaiba balsam oil, polyethylene glycol-40 hydrogenated castor oil, and water were designed. Results of polarized light microscopy, small-angle X-ray scattering, texture-profile analysis, and flow-rheology analysis showed that the Res-loaded liquid-crystalline system had a lamellar structure, textural and mechanical (hardness, compressibility, and adhesiveness) properties, and behaved as a non-Newtonian fluid, showing pseudoplastic behavior upon skin application. Furthermore, all liquid-crystalline systems presented bioadhesive properties that may have assisted in maintaining the anti-inflammatory activity of Res, since the topical application of the Res-loaded lamellar mesophase liquid crystals resulted in edema inhibition in a carrageenan-induced paw-inflammation mouse model. Therefore, Res-loaded lamellar mesophases represent a promising new therapeutic approach for inhibition of skin inflammation.

Clotrimazole microemulsion and microemulsion-based gel: evaluation of buccal drug delivery and irritancy using chick chorioallantoic membrane as the model

OBJECTIVES

To investigate the efficacy of clotrimazole microemulsion (CTZ-ME) and its gel form, clotrimazole microemulsion-based gel (CTZ-MBG), for the treatment of oral candidiasis.

METHODS

CTZ-ME and CTZ-MBG were characterized for droplet size and texture, respectively. The ex-vivo permeation study and irritancy assessment of CTZ-ME and CTZ-MBG were performed using chick chorioallantoic membrane (CAM) as the model. Antifungal activity against Candida albicans ATCC 10 231 of CTZ-ME and CTZ-MBG was determined by agar diffusion method compared to the blank counterparts.

KEY FINDINGS

CTZ-ME contained nano-sized droplets and CTZ-MBG had acceptable firmness and spreadability. CTZ-ME exhibited faster CAM permeation of the drug and larger inhibition zone than CTZ-MBG as the increased viscosity of CTZ-MBG resulted in more retardation and higher fluctuations in drug diffusion. As there were no detectable visual changes in CAM blood vessels after applying CTZ-ME or CTZ-MBG, both formulations were non-irritants.

CONCLUSIONS

CTZ-ME and CTZ-MBG could deliver the drug through CAM, the model for buccal delivery. Additionally, they did not cause irritancy and had effective antifungal activity against C. albicans. The results indicated that CTZ-ME and CTZ-MBG were potential effective antifungal formulations to treat oral candidiasis.

Novel lecithin-integrated liquid crystalline nanogels for enhanced cutaneous targeting of terconazole: development, in vitro and in vivo studies

Terconazole (Tr) is the first marketed, most active triazole for vaginal candidiasis. Owing to poor skin permeation and challenging physicochemical properties, Tr was not employed for the treatment of cutaneous candidiasis. This is the first study to investigate the relevance of novel lecithin-integrated liquid crystalline nano-organogels (LCGs) to improve physicochemical characteristics of Tr in order to enable its dermal application in skin candidiasis. Ternary phase diagram was constructed using lecithin/capryol 90/water to identify the region of liquid crystalline organogel. The selected organogel possessed promising physicochemical characteristics based on particle size, rheological behavior, pH, loading efficiency, and in vitro antifungal activity. Microstructure of the selected organogel was confirmed by polarized light microscopy and transmission electron microscopy. Ex vivo and in vivo skin permeation studies revealed a significant 4.7- and 2.7-fold increase in the permeability of Tr-loaded LCG when compared to conventional hydrogel. Moreover, acute irritation study indicated safety and compatibility of liquid crystalline organogel to the skin. The in vivo antifungal activity confirmed the superiority of LCG over the conventional hydrogel for the eradication of Candida infection. Overall, lecithin-based liquid crystalline organogel confirmed its potential as an interesting dermal nanocarrier for skin targeting purpose.

Clobetasol-loaded nanostructured lipid carriers for epidermal targeting

Objectives

The aim of this study was to investigate in vitro the epidermal targeting potential of clobetasol propionate-loaded nanostructured lipid carriers (CP-NLC) when compared to that of chitosan-coated (CP-NLC-C).

Methods

CP-NLC were prepared by microemulsion method and characterized by dynamic light scattering, transmission electron microscopy, in vitro release and permeation studies. To verify epidermal targeting, permeation studies were performed in two sets of experiments. For the first set, the skin was removed from the diffusion cell and stratum corneum (SC) was separated from the remaining skin (RS). For the second set, the whole epidermis (EP) was separated from the dermis (DER). CP quantification was performed in each skin layer.

Key findings

A novel clobetasol propionate-loaded NLC was produced with 1/5th of the drug dose used in commercial formulations and, even so, presented greater skin permeation. Both chitosan-coated and uncoated NLC enhanced the amount of CP in the epidermis more than 80-fold when compared to the commercial formulation (20.26 ± 2.77; 17.85 ± 0.49 and 0.22 ± 0.02 μg/cm2, respectively). Differently from chitosan-coated NLC, the uncoated NLC did not show dermal retention.

Conclusions

NLC proved to be a system with potential for targeting drug delivery to the epidermal layer.

DA 5505: a novel topical formulation of terbinafine that enhances skin penetration and retention

Topical fungal infections can become severe if left untreated. Efficient treatment modalities for topical fungal infections aid the penetration of antifungal agents deep into viable skin layers. Terbinafine is a fungicidal agent that inhibits ergosterol, an essential fungal component. The main objective of this study was to evaluate skin permeation and retention of a terbinafine-loaded solution containing chitosan as a film former. Comparative assessment of skin permeation and retention was performed using a prepared formulation (DA 5505) and marketed formulations of terbinafine in murine and porcine skin. To mimic fungal infection of skin, keratinized skin was induced in NC/Nga mice. In comparison with the marketed formulations, DA 5505 exhibited significantly better skin permeation. The flux, permeation coefficient, and enhancement ratio of terbinafine were remarkably increased by DA 5505 in comparison with the marketed formulations, and lag time was dramatically reduced. DA 5505 significantly increased cumulative terbinafine retention in viable skin layers in comparison with the marketed solution, suggesting enhanced efficacy. Furthermore, DA 5505 exhibited superior skin permeation in normal skin and keratinized skin. Thus, the DA 5505 formulation has the potential to effectively deliver terbinafine to superficial and deep cutaneous fungal infections.

Development of gel-forming lyophilized formulation with recombinant human thrombin

The objective of this work was development and evaluation of gel-forming lyophilized formulation with recombinant human thrombin for topical administration. The influence of pH, ionic strength and buffer type on protein stability was evaluated as part of the pre-formulation screening studies. Results indicated an optimal pH from 6.0 to 7.0 and increased stability with increasing content of sodium chloride. The tested buffer types had no significant effect on thrombin stability. For further development, thermosensitive Pluronic® F-127 was employed as a bulking and gelling agent. Physical and mechanical characterization and viscosity measurement confirmed the gel-forming properties of the formulation at the application temperature of 32 °C. Several techniques (addition of well-soluble polyols, different freezing protocols and reconstitution under vacuum) were tested to decrease the reconstitution time. The obtained results revealed that a vacuum in the vial headspace is crucial for acceptable reconstitution. The freeze drying process has no negative impact on recombinant thrombin stability, and this was confirmed by reverse-phase-HPLC, activity assay and optical density measurements.

Optimization and characterization of chitosan films for transdermal delivery of ondansetron

The aim of this study was to develop novel transdermal films of ondansetron HCl with high molecular weight chitosan as matrix polymer and 2-(2-ethoxy-ethoxy) ethanol (Transcutol®) as plasticizer. In this context, firstly the physicochemical properties of gels used to formulate transdermal films were characterized and, physicochemical properties and bioadhesiveness of the transdermal films prepared with chitosan gels were assessed. The impact of three different types of terpenes, namely limonene, nerolidol and eucalyptol on in vitro skin permeation of ondansetron from transdermal films were also examined. ATR-FTIR measurements were performed to investigate the effects of the chitosan film formulations on in vitro conformational order of stratum corneum intercellular lipids after 24 h permeation study. The results showed that the chitosan gels consisting of Transcutol® as plasticizer and terpenes as penetration enhancer may be used to prepare transdermal films of ondansetron due to the good mechanical properties and bioadhesiveness of the transdermal films. Eucalyptol (1%) showed higher permeation enhancer effect than the other terpenes and control. ATR-FTIR data confirmed that finding in which eucalyptol induced a blue shift in the both CH₂ asymmetric and symmetric absorbance peak positions indicating increased lipid fluidity of stratum corneum.

A novel preparation method for organogels: high-speed homogenization and micro-irradiation

The aim of this work was to prepare organogels of Carbopol 974P NF (C974) in PEG 400 by using a novel technique, high-speed homogenization followed by microwave heating. Triclosan (TCS) was used as a model drug. C974, at concentrations ranging between 2% and 4%, was dispersed in 25 ml of PEG 400, and the dispersion was homogenised for 5 min at 24,000 rpm. The dispersion was either heated at 80°C in water bath under mechanic stirring at 200 rpm or exposed to micro-irradiation (1,200 W/1 h) for 2 min. The formulations prepared with both methods performed a well-structured gel matrix characteristic at 3% and 4% of C974 concentrations. As the concentrations of the polymer increased, the elastic properties also increased. The viscosity profiles indicated a shear-thinning system. DSC data revealed that TCS was dissolved in gel. Skin accumulation ability of TCS had been improved by these novel organogels regardless of the preparation method. TCS was still microbiologically effective after the microwave process was applied. It was determined that microwave heating is a suitable method to obtain C974 organogels. This novel production technique developed might be promising especially in industrial scale when the dramatic reduction in the preparation time and energy were considered.

Preparation and evaluation of warfarin-β-cyclodextrin loaded chitosan nanoparticles for transdermal delivery

The main objective of the present work was to prepare warfarin-β-cyclodextrin (WAF-β-CD) loaded chitosan (CS) nanoparticles for transdermal delivery. CS is a hydrophilic carrier therefore, to overcome the hydrophobic nature of WAF and allow its incorporation into CS nanoparticles, WAF was first complexed with β-cyclodextrin (β-CD). CS nanoparticles were prepared by ionotropic pre-gelation using tripolyphosphate (TPP). Morphology, size and structure characterization of nanoparticles were carried out using SEM, TEM and FTIR, respectively. Nanoparticles prepared with 3:1 CS:TPP weight ratio and 2mg/ml final CS concentration were found optimum. They possessed spherical particles (35±12nm diameter) with narrow size distribution (PDI=0.364) and 94% entrapment efficiency. The in vitro release as well as the ex vivo permeation profiles of WAF-β-CD from the selected nanoparticle formulation were studied at different time intervals up to 8h. In vitro release of WAF-β-CD from CS nanoparticles followed a Higuchi release profile whereas its ex vivo permeation (at pH 7.4) followed a zero order permeation profile. Results suggested that the developed WAF-β-CD loaded CS carrier could offer a controlled and constant delivery of WAF transdermally.

Preparation and evaluation of quercetin-loaded lecithin-chitosan nanoparticles for topical delivery

BACKGROUND

The purpose of this study was to investigate lecithin-chitosan nanoparticles as a topical delivery system for quercetin.

METHODS

Tocopheryl propylene glycol succinate was chosen to be the surfactant for the nanosystem. The mean particle size of the nanoparticles was 95.3 nm, and the entrapment efficiency and drug loading for quercetin were 48.5% and 2.45%, respectively. Topical delivery in vitro and in vivo of the quercetin-loaded nanoparticles was evaluated using quercetin propylene glycol solution as the control.

RESULTS

Compared with quercetin solution, the quercetin-loaded nanoparticles showed higher permeation ability, and significantly increased accumulation of quercetin in the skin, especially in the epidermis. Microstructure observation of the skin surface after administration indicated that the interaction between ingredients of the nanoparticles and the skin surface markedly changed the morphology of the stratum corneum and disrupted the corneocyte layers, thus facilitating the permeation and accumulation of quercetin in skin.

CONCLUSION

Lecithin-chitosan nanoparticles are a promising carrier for topical delivery of quercetin.

Preparation, characterization, and in vitro permeation study of terbinafine HCl in poloxamer 407-based thermogelling formulation for topical application

Upon topical administration, a high penetration rate of antifungal drug into the infected site is desirable to reduce treatment length and systemic side effects which occur especially after a prolonged peroral administration. Thermogelling formulations composed of poloxamer 407, medium chain triglycerides, isopropyl alcohol, dimethyl isosorbide, and water for topical application were developed, and a lipophilic drug terbinafine HCl (TBF) was incorporated. Previously, a remarkable high permeation rate of a hydrophilic drug 5-aminolevulinic acid from this vehicle was evident compared to different creams from German Pharmacopoeia. By varying the composition of vehicle constituents, a broad range of consistencies and appearances was obtained. Up to 4% TBF could be solubilized in the vehicle. TBF fluxes at steady state across human stratum corneum from these formulations were higher than those from the German Pharmacopoeia Basiscreme Deutscher Arzneimittel Codex and a marketed product at similar concentration of 1%. TBF fluxes increased along with a higher content of TBF in the formulation. The amount of TBF retained in stratum corneum was higher compared to those from both standards of comparison (p < 0.01). The thermodynamic activity of TBF in the thermogelling formulation was lower compared to those in other formulations. Therefore, the nature of the vehicle and its interaction with TBF are suggested to play a significant role in explaining higher fluxes along with higher TBF content. Differential scanning calorimetry measurements revealed comparable T2 and T3 endothermic shifts from all examined formulations suggesting equal influences to the skin lipids.