Afzal Hussain

Nanoemulsion gel-based topical delivery of an antifungal drug: in vitro activity and in vivo evaluation

Abstract Objective: In this study, attempt has been focused to prepare a nanoemulsion (NE) gel for topical delivery of amphotericin B (AmB) for enhanced as well as sustained skin permeation, in vitro antifungal activity and in vivo toxicity assessment. Materials and methods: A series of NE were prepared using sefsol-218 oil, Tween 80 and Transcutol-P by slow spontaneous titration method. Carbopol gel (0.5% w/w) was prepared containing 0.1% w/w AmB. Furthermore, NE gel (AmB-NE gel) was characterized for size, charge, pH, rheological behavior, drug release profile, skin permeability, hemolytic studies and ex vivo rat skin interaction with rat skin using differential scanning calorimeter. The drug permeability and skin irritation ability were examined with confocal laser scanning microscopy and Draize test, respectively. The in vitro antifungal activity was investigated against three fungal strains using the well agar diffusion method. Histopathological assessment was performed in rats to investigate their toxicological potential. Results and discussion: The AmB-NE gel (18.09 ± 0.6 µg/cm2/h) and NE (15.74 ± 0.4 µg/cm2/h) demonstrated the highest skin percutaneous permeation flux rate as compared to drug solution (4.59 ± 0.01 µg/cm2/h) suggesting better alternative to painful and nephrotoxic intravenous administration. Hemolytic and histopathological results revealed safe delivery of the drug. Based on combined results, NE and AmB-NE gel could be considered as an efficient, stable and safe carrier for enhanced and sustained topical delivery for AmB in local skin fungal infection. Conclusion: Topical delivery of AmB is suitable delivery system in NE gel carrier for skin fungal infection.

Elastic liposome-based gel for topical delivery of 5-fluorouracil: in vitro and in vivo investigation

Abstract Objective: This investigation has focused to characterize the elastic liposome containing 5-fluorouracil (5-FU) and to enhance drug permeation across stratum corneum (SC) of the skin (rat) using various surfactants and in vivo dermal toxicity evaluation. Methodology: 5-FU-loaded elastic liposomes were developed, prepared and characterized for their entrapment efficiency, vesicle size, number of vesicles, morphological characteristics, surface charge and turbidity. In vitro drug release profile, in vitro skin permeation potential and in vitro hemolytic ability of the formulation have been evaluated to compare with drug solution for 24 h. In vitro skin permeation potential was also compared with marketed cream. Furthermore, in vivo skin irritation potential, drug penetration into the skin using confocal laser scanning microscopy (CLSM) and in vivo toxicity studies were performed. Results and conclusions: The optimized elastic liposomes demonstrated maximum drug entrapment efficiency, optimum vesicular size and considerable elasticity. In vitro skin permeation studies showed the highest drug permeation flux like 77.07 ± 6.34, 89.74 ± 8.5 and 70.90 ± 9.6 µg/cm2/h for EL3-S60, EL3-S80 and EL3-T80, respectively, as compared to drug solution (8.958 ± 6.9 µg/cm2/h) and liposome (36.80 ± 6.4 µg/cm2/h). Drug deposition of optimized elastic liposome EL3-S80 was about three fold higher than drug solution. Skin irritation and CLSM studies suggested that optimized gel was free from skin irritation and capable to deliver 5-FU into the epidermal area for enhanced topical delivery than drug solution. The in vitro study showed minimum hemolysis in the optimized formulation. Finally, in vivo toxicity studies followed with hisptopathological assessment showed that elastic liposome was able to extract SC to improve drug permeation without changing general anatomy of the skin.

Enhanced stability and permeation potential of nanoemulsion containing sefsol-218 oil for topical delivery of amphotericin B

Abstract Aim: To characterize the enhanced stability and permeation potential of amphotericin B nanoemulsion comprising sefsol-218 oil at varying pH and temperature of aqueous continuous phase. Methodology: Several batches of amphotericin B loaded nanoemulsion were prepared and evaluated for their physical and chemical stability at different pH and temperature. Also, a comparative study of ex vivo drug permeation across the albino rat skin was investigated with commercial Fungisome® and drug solution at 37 °C for 24 h. The extent of drug penetrated through the rat skin was thereby evaluated using the confocal laser scanning microscopy (CLSM). Results and conclusions: The optimized nanoemulsion demonstrated the highest flux rate 17.85 ± 0.5 µg/cm2/h than drug solution (5.37 ± 0.01 µg/cm2/h) and Fungisome® (7.97 ± 0.01 µg/cm2/h). Ex vivo drug penetration mechanism from the developed formulations at pH 6.8 and pH 7.4 of aqueous phase pH using the CLSM revealed enhanced penetration. Ex vivo drug penetration studies of developed formulation comprising of CLSM revealed enhanced penetration in aqueous phase at pH 6.8 and 7.4. The aggregation behavior of nanoemulsion at both the pH was found to be minimum and non-nephrotoxic. The stability of amphotericin B was obtained in terms of pH, optical density, globular size, polydispersity index and zeta potential value at different temperature for 90 days. The slowest drug degradation was observed in aqueous phase at pH 7.4 with shelf life 20.03-folds higher when stored at 4 °C (3.8 years) and 5-fold higher at 25 °C (0.951 years) than at 40 °C. The combined results suggested that nanoemulsion may hold an alternative for enhanced and sustained topical delivery system for amphotericin B.

Formulation and optimization of nanoemulsion using antifungal lipid and surfactant for accentuated topical delivery of Amphotericin B

Abstract The objective of the study was to develop, optimize and evaluate a nanoemulsion (NE) of Amphotericin B (AmB) using excipients with inherent antifungal activities (Candida albicans and Aspergillus niger) for topical delivery. AmB-loaded NE was prepared using Capmul PG8 (CPG8), labrasol and polyethylene glycol-400 by spontaneous titration method and evaluated for mean particle size, polydispersity index, zeta potential and zone of inhibition (ZOI). NE6 composed of CPG8 (15%w/w), Smix (24%w/w) and water (61%w/w) was finally selected as optimized NE. AmB-NE6 was studied for improved in vitro release, ex vivo skin permeation and deposition using the Franz diffusion cell across the rat skin followed with drug penetration using confocal laser scanning microscopy (CLSM) as compared to drug solution (DS) and commercial Fungisome®. The results of in vitro studies exhibited the maximum ZOI value of NE6 as 19.1 ± 1.4 and 22.8 ± 2.0 mm against A. niger and C. albicans, respectively, along with desired globular size (49.5 ± 1.5 nm), zeta potential (−24.59 mV) and spherical morphology. AmB-NE6 revealed slow and sustained release of AmB as compared to DS in buffer solution (pH 7.4). Furthermore, AmB-NE6 elicited the highest flux rate (22.88 ± 1.7 μg/cm2/h) as compared to DS (2.7 ± 0.02 μg/cm2/h) and Fungisome® (11.5 ± 1.0 μg/cm2/h). Moreover, the enhancement ratio and drug deposition were found to be highest in AmB-NE6 than DS across the stratum corneum barrier. Finally, CLSM results corroborated enhanced penetration of the AmB-NE6 across the skin as compared to Fungisome® and DS suggesting an efficient, stable and sustained topical delivery.

New Perspectives in the Topical Delivery of Optimized Amphotericin B Loaded Nanoemulsions Using Excipients with Innate Anti-fungal Activities: A Mechanistic and Histopathological Investigation.

This study aimed to develop nanoemulsions (NEs) for the topical delivery of Amphotericin B using lipids and surfactants with innate antifungal activity. NEs were formulated by a slow spontaneous titration method and characterized for particle size, polydispersity index, zeta potential, zone of inhibition (ZOI), in vitro release, enhanced ex vivo rat skin permeation-deposition, hemolysis followed by interaction with the skin using scanning electron microscopy, and histopathology. The ZOI values of the optimized NEs (ANE3) were 21.8±1.5 and 19.7±1.2 mm against A. fumigatus and C. albicans, respectively. The explored excipients and optimized ANE3 elicited hemo-biocompatibility. ANE3 exhibited in vitro sustained release and an enhanced flux value (21.62±1.6 μg/cm2/h) as compared to the drug solution and Fungisome without displaying toxicity. Conclusively, ANE3 could be a promising therapeutic approach with enhanced efficacy and safety for treating a wide range of fungal infections topically.

Elastic liposomes as novel carriers: recent advances in drug delivery

Elastic liposomes (EL) are some of the most versatile deformable vesicular carriers that comprise physiologically biocompatible lipids and surfactants for the delivery of numerous challenging molecules and have marked advantages over other colloidal systems. They have been investigated for a wide range of applications in pharmaceutical technology through topical, transdermal, nasal, and oral routes for efficient and effective drug delivery. Increased drug encapsulation efficiency, enhanced drug permeation and penetration into or across the skin, and ultradeformability have led to widespread interest in ELs to modulate drug release, permeation, and drug action more efficiently than conventional drug-release vehicles. This review provides insights into the versatile role that ELs play in the delivery of numerous drugs and biomolecules by improving drug release, permeation, and penetration across the skin as well as stability. Furthermore, it provides future directions that should ensure the widespread use of ELs across all medical fields.

Evidences for anti-mycobacterium activities of lipids and surfactants

Tuberculosis is the most widespread and deadly airborne disease caused by Mycobacterium tuberculosis. The two-pronged lethal effect on the bacteria using lipids/surfactants and anti-tubercular drugs may render the miniaturization of dose owing to synergistic and tandem effect of both. The current research has been focused on screening and evaluating various lipids/surfactants possessing inherent anti-mycobacterium activity that can ferry the anti-tubercular drugs. In vitro anti-mycobacterium activity was evaluated using agar well diffusion method. Furthermore, time-concentration dependent killing and DNA/RNA content release studies were performed to correlate the findings. The exact mechanism of bacterial killing was further elucidated by electron/atomic force microscopy studies. Finally, to negate any toxicity, in vitro hemolysis and toxicity studies were performed. The study revealed that capmul MCM C-8, labrasol and acconon C-80 possessed highest in vitro anti-mycobacterium activity. Electron/atomic force microscopy results confirmed in vitro studies and verified the killing of Mycobacterium owing to the release of cytoplasmic content after cell wall fragmentation and disruption. Moreover, the least hemolysis and hundred percent survivals rate of mice using the excipients demonstrated the safety aspects of explored excipients that can ferry the anti-tubercular drugs. The present study concluded the safe, efficient and synergistic activity of the explored excipients and anti-tubercular drugs in controlling the menace of tuberculosis.

Optimized permeation enhancer for topical delivery of 5-fluorouracil-loaded elastic liposome using Design Expert: part II

Abstract Objective: To prepare and optimize the topical elastic liposome (EL)-loaded carbopol-980 gel of 5-Fluorouracil (5-FU) containing permeation enhancers (azone, propylene glycol (PG) and lauryl alcohol (LA)) and further evaluation for permeation flux of 5-FU, the activation energy and irritation in the rat skin. Methods: EL formulations were prepared using phosphatidylcholine and varied surfactants (Span 60, Span 80 and Tween-80) by rotator evaporation method and optimized by experimental design. In vitro characterizations dictated the EL containing Span 80 (lipid:surfactant = 7:3) (EL3-S80) for further optimization of gel. Different gel formulations (5% w/w) with varying concentration (1–3%) of permeation enhancers were prepared and evaluated for viscosity, spreadability, the 5-FU permeation and deposition. The activation energy using the Franz diffusion cell and the plausible irritation using the Draize test were assessed on the albino rat and rabbit, respectively. Results and discussion: EL3-S80 was selected as an optimized EL owing to maximum desirability (0.99) and enhanced 5-FU flux (187.86 ± 14.1 μg/cm2/h). EL3-S80 suspension loaded gels (0.5%) revealed reduced viscosity leading to higher spreadability than blank gel. EL containing 3% azone in gel, EL containing 3% LA in gel and EL containing 3% PG in gel portrayed 187.86 ± 14.1, 117.7 ± 13.4 and 106.7 ± 7.3 μg/cm2/h as enhanced 5-FU flux values, respectively as compared to drug solution (8.8 ± 0.76 μg/cm2/h). Furthermore, reduced value of activation energy (2.63-folds) and the non-irritancy of gel could be effective and safe. Conclusion: ELA-3 gel formulation could be used as an effective and economic gel in cutaneous cancer and skin-related keratoses.

Experimental design-based optimization of lipid nanocarrier as delivery system against Mycobacterium species: in vitro and in vivo evaluation

Abstract The study aimed to optimize self-nanoemulsifying drug delivery system using experimental design using excipients holding innate anti-mycobacterium activities followed with characterizations for responses such as optical clarity (Y1), zone of inhibition (ZOI) against Mycobacterium smegmatis strains (Y2, Y3), and globular size (Y4). The optimized formulations (OF1–OF3) were further characterized for responses and evaluated for zeta potential, minimum inhibition concentration (MIC) against non-pathogenic and tubercular strains, morphological (electron microscopy and atomic force microscopy), and confocal laser scanning microscopy (CLSM) studies. The desirability analysis suggested that the predicted values of the OF1 for the responses Y1, Y2, Y3, and Y4 were 0.137, 22.77 mm, 21.9 mm, and 191.11 nm, respectively. The morphological assessment confirmed the in vitro studies and established the inhibition mechanism as evidenced with oozing, ablation, and cell-wall fragmentation followed with cell disruption. The OF1, OF2, and OF3 showed an MIC value at 8.8 ± 0.56 mg/ml, 12.5 ± 0.22 mg/ml, and 15.0 ± 0.4 mg/ml, respectively, corroborating effectiveness against tubercular strain. CLSM studies revealed 75.1, 80.3, and 88.7% as an intense fluorescence intensity of OF1, OF2, and OF3, respectively, as compared with dye solution (∼53%). Conclusively, it can be inferred that the delivery of anti-tubercular drugs might be reassessed using excipients with inherent anti-mycobacterium activities.

In vitro -In vivo- In silico Simulation of Experimental Design Based Optimized Curcumin Loaded Multiparticulates System

The present study focused to optimize dual coated multiparticulates using Box-Behnken Experimental Design and in-silico simulation using GastroPlusTM software. The optimized formulations (OB1 and OB2) were comparatively evaluated for particle size, morphological, in vitro drug release, and in vivo permeation studies. In silico simulation study predicted the in vivo performance of the optimized formulation based on in-vitro data. Results suggested that optimized formulation was obtained using maximum content of Eudragit FS30D and minimum drying time (2 min). In vitro data corroborated that curcumin release was completely protected from premature drug release in the proximal part of gastro intestinal tract and successfully released to the colon (95%) which was closely predicted (90.1 %) by GastroPlusTM simulation technique. Finally, confocal laser scanning microscopy confirmed the in-vitro findings wherein maximum intensity was observed with OB1 treated group suggesting successful delivery of OB1 to the colon for enhanced absorption as predicted in regional absorption profile in ascending colon (30.9%) and caecum (23.2%). Limited drug absorption was predicted in small intestine (1.5-8.7%). The successful outcomes of the research work minimized the release of curcumin in the upper gastric tract and the maximized drug access to the colon (pH 7.4) as prime concern.