In vitro assessment of pharmaceutical potential of ethosomes entrapped with terbinafine hydrochloride

Ethosomes-mediated tryptanthrin delivery as efficient anti-psoriatic nanotherapy by enhancing topical drug absorption and lipid homeostasis

Psoriasis is a chronic, relapsing, and refractory immune-mediated skin disease with the etiology and pharmaceutical targets remaining unsatisfactorily addressed. Topical herbal-derived compounds, such as tryptanthrin (Tryp), have been considered as an alternative therapy for psoriasis due to their lower costs and fewer side effects compared to other therapies. However, the effectiveness of topically administered drugs is substantially limited by the thickened pathological skin barrier and the low bioavailability of drugs in the deeper layers of the lesion. Ethosomes, being a novel phospholipid-based vesicle system with high content of ethanol, have been implicated in enhancing topical drug absorption and restoring psoriatic lesions. In this study, taking advantages of ethosomes as a soft and malleable drug carrier, we constructed the Tryp-loaded ethosome (Tryp-ES) through a one-step microfluidics-based technique. The optimal formulation of Tryp-ES was achieved by adding amino-acid-derived surfactant sodium lauroyl glutamate, and Tryp-ES exhibited homogeneous particle size and favorable stability at room temperature. In vitro evaluations showed that Tryp of Tryp-ES could be easily internalized into cells and accumulated in cell nuclei, hence inhibited the abnormally proliferated keratinocytes by inducing apoptosis. In vivo and in vitro assessment using psoritic skin of mice revealed that Tryp-ES had preferred skin retention and permeation of loaded drugs within the initial 1 h of topical administration, which could be attributed to transient disintegrations of cell membranes by ethosomes, thus improved cellular fluidity and permeability. Notably, a synergistic effect of ethosomes and Tryp was found in psoriatic mice. Tryp-ES-treated mice showed substantially ameliorated symptoms of psoriasis and reduced pathological alterations due to hyperplasia, inflammation and angiogenesis, without detectable local or systemic toxicities. Interestingly, lipidomics analysis confirmed that the supplementation of phospholipids, as in the form of ethosome vehicles, was an alterantive strategy to relieve psoriatic pathologies. Taken together, this study provides a novel impact for ethosomal topical delivery of Tryp and underlines their potential as an effective therapy for the management of psoriasis.

Rutin-Loaded Transethosomal Gel for Topical Application: A Comprehensive Analysis of Skin Permeation and Antimicrobial Efficacy

This study conducts a systematic investigation of the creation and optimization of a rutin-loaded transethosome intended for topical use. The formulation's characteristics were thoroughly assessed for vesicle size (160.45 ± 1.98 nm), polydispersity index (0.235 ± 0.067), and zeta potential (-22.89 mV), with an entrapment efficiency and drug loading of 89.99 ± 1.55% and 8.9 ± 2.11%, respectively, and found to have a spherical shape by the use of transmission electron microscopy. The conversion to a gel suitable for application on the skin was carried out. The drug release form Opt-RUT-TE formulation (73.61 ± 2.55%) was significantly higher than that of release form RUT-suspension (34.52 ± 1.19%). The drug that permeated the skin from Opt-RUT-TEG (935.25 ± 10.49 μg/cm2) was significantly higher than the permeability from RUT-Suspension gel (522.57 ± 6.79 μg/cm2). Notably, tape stripping analysis revealed that the Opt-RUT-TE gel effectively penetrated the skin layers, with a higher concentration observed in the epidermis-dermis than in the RUT-suspension gel. The transethosomal gel exhibited favorable characteristics, highlighting its capacity to efficiently permeate the skin and suppress the growth of microorganisms, and Opt-RUT-TEG showed a higher microorganism inhibition zone (Gram-positive bacteria) than that of RUT-suspension gel. The investigation highlights the significant therapeutic possibilities of rutin in a transethosomal gel formulation for treating dermatological diseases by improving skin permeability and exhibiting antibacterial effects.

Ethosomes: a potential nanovesicular carrier to enhancing the drug delivery against skin barriers

Ethosomes, which are liposomes like structures, mainly composed primarily of ethanol, have attracted considerable attention due to their potential to enhance the drug permeation via skin. The article discusses the formulation and preparation methods of ethosomes, offering insights into the various factors that influence their size, shape, and stability. Moreover, it explores the techniques used to assess the physicochemical properties of ethosomes and their impact on drug delivery effectiveness. The article also elucidates the mechanism by which ethosomes enhance skin permeation, emphasising their ability to modify the lipid structure and fluidity of the stratum corneum. Additionally, the review investigates the applications of ethosomes in diverse drug delivery scenarios, including the delivery of small molecules, peptides, and phytoconstituents. It highlights the potential of ethosomes to improve drug bioavailability, extend drug release, and achieve targeted delivery to specific skin layers or underlying tissues.

Polymer Characteristics for Drug Layering on Particles Using a Novel Melt Granulation Technology, MALCORE®

MALCORE®, a novel manufacturing technology for drug-containing particles (DCPs), relies on the melt granulation method to produce spherical particles with high drug content. The crucial aspect of particle preparation through MALCORE® involves utilizing polymers that dissolve in the melt component, thereby enhancing viscosity upon heating. However, only aminoalkyl methacrylate copolymer E (AMCE) has been previously utilized. Therefore, this study aims to discover other polymers and comprehend the essential properties these polymers need to possess. The results showed that polyvinylpyrrolidone (PVP) was soluble in the stearic acid (SA) melt component. FTIR examination revealed no interaction between SA and polymer. The phase diagram was used to analyze the state of the SA and polymer mixture during heating. It revealed the mixing ratio and temperature range where the mixture remained in a liquid state. The viscosity of the mixture depended on the quantity and molecular weight of the polymer dissolved in SA. Furthermore, the DCPs prepared using PVP via MALCORE® exhibited similar pharmaceutical properties to those prepared with AMCE. In conclusion, understanding the properties required for polymers in the melt granulation process of MALCORE® allows for the optimization of manufacturing conditions, such as temperature and mixing ratios, for efficient and consistent drug layering.

Novel Transethosomal Gel Containing Miconazole Nitrate; Development, Characterization, and Enhanced Antifungal Activity

Miconazole nitrate (MCNR) is a BCS class II antifungal drug with poor water solubility. Although numerous attempts have been made to increase its solubility, formulation researchers struggle with this significant issue. Transethosomes are promising novel nanocarriers for improving the solubility and penetration of drugs that are inadequately soluble and permeable. Thus, the objective of this study was to develop MCNR-loaded transethosomal gel in order to enhance skin permeation and antifungal activity. MCNR-loaded transethosomes (MCNR-TEs) were generated using the thin film hydration method and evaluated for their zeta potential, particle size, polydispersity index, and entrapment efficiency (EE%). SEM, FTIR, and DSC analyses were also done to characterize the optimized formulation of MCNR-TEs (MT-8). The optimized formulation of MCNR-TEs was incorporated into a carbopol 934 gel base to form transethosomal gel (MNTG) that was subjected to ex vivo permeation and drug release studies. In vitro antifungal activity was carried out against Candida albicans through the cup plate technique. An in vivo skin irritation test was also performed on Wistar albino rats. MT-8 displayed smooth spherical transethosomal nanoparticles with the highest EE% (89.93 ± 1.32%), lowest particle size (139.3 ± 1.14 nm), polydispersity index (0.188 ± 0.05), and zeta potential (-18.1 ± 0.10 mV). The release profile of MT-8 displayed an initial burst followed by sustained release, and the release data were best fitted with the Korsmeyer-Peppas model. MCNR-loaded transethosomal gel was stable and showed a non-Newtonian flow. It was found that ex vivo drug permeation of MNTG was 48.76%, which was significantly higher than that of MNPG (plain gel) (p ≤ 0.05) following a 24-h permeation study. The prepared MCNR transethosomal gel exhibited increased antifungal activity, and its safety was proven by the results of an in vivo skin irritation test. Therefore, the developed transethosomal gel can be a proficient drug delivery system via a topical route with enhanced antifungal activity and skin permeability.

Statistical optimization of tetrahydrocurcumin loaded solid lipid nanoparticles using Box Behnken design in the management of streptozotocin-induced diabetes mellitus

In the past, curcumin was the go-to medication for diabetes, but recent studies have shown that tetrahydrocurcumin is more effective. The problem is that it's not very soluble in water or very bioavailable. So, our research aims to increase the bioavailability and anti-diabetic efficacy of tetrahydrocurcumin in streptozotocin-induced diabetic rats by synthesizing tetrahydrocurcumin-loaded solid lipid nanoparticles. Box Behnken Design was employed for the optimization of tetrahydrocurcumin-loaded solid lipid nanoparticles (THC-SLNs). The optimal formulation was determined by doing an ANOVA to examine the relationship between the independent variables (drug-to-lipid ratio, surfactant concentration, and co-surfactant concentration) and the dependent variables (particle size, percent entrapment efficiency, and PDI). Particle size, PDI, and entrapment efficiency all showed statistical significance based on F-values and p-values. The optimized batch was prepared using a drug-to-lipid ratio (1:4.16), 1.21% concentration of surfactant, and 0.4775% co-surfactant (observed with a particle size of 147.1 nm, 83.58 ± 0.838 % entrapment efficiency, and 0.265 PDI, and the values were found very close with the predicted ones. As the THC peak vanishes from the DSC thermogram of the improved formulation, this indicates that the drug has been transformed from its crystalline form into its amorphous state. TEM analysis of optimized formulation demonstrated mono-dispersed particles with an average particle size of 145 nm which are closely related to zetasizer's results. In-vitro release study of optimized formulation demonstrated burst release followed by sustained release up to 71.04% throughout 24 hrs. Increased bioavailability of the adjusted THC-SLN was found in an in vivo pharmacokinetics research with 9.47 folds higher AUC(0-t) compared to plain THC-suspension. Additionally, pharmacodynamic experiments of optimized formulation demonstrated a marked decrease in blood glucose level to 63.7% and increased body weight from 195.8 ± 7.223 to 231.2 ± 7.653 on the 28th day of the study and showed a better anti-diabetic effect than plain drug suspension. Results of stability studies revealed that formulation can be stored for longer periods at room temperature. Tetrahydrocurcumin can be effectively administered by SLN for the treatment of diabetes.

Design and Characterization of an Ethosomal Gel Encapsulating Rosehip Extract

Rising environmental awareness drives green consumers to purchase sustainable cosmetics based on natural bioactive compounds. The aim of this study was to deliver Rosa canina L. extract as a botanical ingredient in an anti-aging gel using an eco-friendly approach. Rosehip extract was first characterized in terms of its antioxidant activity through a DPPH assay and ROS reduction test and then encapsulated in ethosomal vesicles with different percentages of ethanol. All formulations were characterized in terms of size, polydispersity, zeta potential, and entrapment efficiency. Release and skin penetration/permeation data were obtained through in vitro studies, and cell viability was assessed using an MTT assay on WS1 fibroblasts. Finally, ethosomes were incorporated in hyaluronic gels (1% or 2% w/v) to facilitate skin application, and rheological properties were studied. Rosehip extract (1 mg/mL) revealed a high antioxidant activity and was successfully encapsulated in ethosomes containing 30% ethanol, having small sizes (225.4 ± 7.0 nm), low polydispersity (0.26 ± 0.02), and good entrapment efficiency (93.41 ± 5.30%). This formulation incorporated in a hyaluronic gel 1% w/v showed an optimal pH for skin application (5.6 ± 0.2), good spreadability, and stability over 60 days at 4 °C. Considering sustainable ingredients and eco-friendly manufacturing technology, the ethosomal gel of rosehip extract could be an innovative and green anti-aging skincare product.

Development and Evaluation of Ethosomes Loaded with Zingiber zerumbet Linn Rhizome Extract for Antifungal Skin Infection in Deep Layer Skin

Skin fungal infection is still a serious public health problem due to the high number of cases. Even though medicines are available for this disease, drug resistance among patients has increased. Moreover, access to medicine is restricted in some areas. One of the therapeutic options is herbal medicine. This study aims to develop an ethosome formulation loaded with Zingiber zerumbet (L.) Smith. rhizome extract for enhanced antifungal activity in deep layer skin, which is difficult to cure. Ethosomes were successfully prepared by the cold method, and the optimized formulation was composed of 1% (w/v) phosphatidylcholine and 40% (v/v) ethanol. Transmission electron microscope (TEM) images revealed that the ethosomes had a vesicle shape with a diameter of 205.6-368.5 nm. The entrapment of ethosomes was 31.58% and could inhibit the growth of Candida albicans at a concentration of 312.5 μg/mL. Finally, the ethosome system significantly enhanced the skin penetration and retention of the active compound (zerumbone) compared with the liquid extract. This study showed that Z. zerumbet (L.) rhizome extract could be loaded into ethosomes. The findings could be carried over to the next step for clinical application by conducting further in vivo penetration and permeation tests.

Assessment of Brassica oleraceae L. (Brassicaceae) extract loaded ethosomal gel as a versatile vesicular carrier system for dermocosmetic application: A noninvasive split-faced study

BACKGROUND

Plant extracts with rich ascorbic acid contents have greater antioxidant capability; extensively employed in skin beautifying products and protect skin from detrimental photodamaging environmental effects. Brassica oleraceae is having a substantial prospective toward cosmeceuticals owed by its profound activity against oxidation.

AIM

To develop an effective topical ethosomal gel loaded with Brassica oleraceae leaves extract with significant antioxidant activity.

METHODOLOGY

Valuation of antioxidant capability of plant leaves extract by 2,2-diphenyl-1-picrylhydrazyl (DPPH), and quantification of ascorbic acid was done through high performance liquid chromatography (HPLC). Ethosomes were prepared by cold method. Optimized suspension containing extract was incorporated in 2% Carbopol gel (test) along with extract solution (control). Noninvasive in vivo studies were performed for final product to assess its effects on skin by measuring melanin and erythema, sebum level, elasticity, moistness level, facial pores count and their area, skin wrinkling, and smoothness.

RESULTS

Brassica oleraceae (red cabbage) leaves extract exhibited significant antioxidant potential (85.64 ± 1.28%) with 14.22 μg/g of ascorbic acid; expressed prominent cosmetic effects in terms of skin melanin, erythema, sebum, elasticity, hydration, facial pores, wrinkles, and smoothness when incorporated in ethosomes. ANOVA test also exhibited positive significant (p ≤ 0.05) effects on skin.

CONCLUSION

Brassica oleraceae extract is a strong antioxidant with remarkable dermocosmetic benefits for skin.

Trans ethosomal hybrid composites of naproxen-sulfapyridine in hydrogel carrier: anti-inflammatory response in complete Freund's adjuvant induced arthritis rats

Current treatment for Rheumatoid arthritis (RA) utilizes Disease-modifying antirheumatic drugs, non-steroidal anti-inflammatory drugs or its combination, to decrease joint inflammation. In the present study, naproxen (NAP) and sulfapyridine (SULF) ethosomes were prepared by a thin-film hydration technique using PL90G and cholesterol, later crosslinked with carbopol®934. The ethosomes and ethosomal hydrogel were evaluated for rheological properties, physico-chemical analysis, in vitro and in vivo study. The results show, NAP and SULF ethosomes exhibited an average vesicle size between 251.1 ± 1.80-343.5 ± 3.23 nm and 269.0 ± 1.17-358.8 ± 1.22 nm, respectively, with good stability (zeta potential > 30 mV) and polydispersity index. Differential scanning calorimeter and Fourier transform infrared studies reveal no significant changes in the drug properties of ethosomes. Transmission electron microscopy analysis discloses spherical shape vesicles below 200 nm. The entrapment efficiency of NAP and SULF ethosomes was above 66%, and NAP-SULF ethosomes-hydrogel (EH) exhibited a sustained release effect (>8 h). In vivo studies on NAP-SULF EH shows significant inhibition of inflammation (84.63%), with less paw volume (0.1935 ± 0.08 ml) on induced arthritis Albino Wistar rats, (p < .01). NAP-SULF EH was stable at 25 °C ± 0.5 for 3-months. To conclude, a hybrid composite of NAP-SULF in hydrogel carrier prevents inflammation effectively, and could be novel for trans delivery of drugs in RA.

Therapeutic Textiles Functionalized with Keratin-Based Particles Encapsulating Terbinafine for the Treatment of Onychomycosis

Onychomycosis is the most common nail fungal infection worldwide. There are several therapy options available for onychomycosis, such as oral antifungals, topicals, and physical treatments. Terbinafine is in the frontline for the treatment of onychomycosis; however, several adverse effects are associated to its oral administration. In this work, innovative keratin-based carriers encapsulating terbinafine were designed to overcome the drawbacks related to the use this drug. Therapeutic textiles functionalized with keratin-based particles (100% keratin; 80% keratin/20% keratin-PEG) encapsulating terbinafine were developed. The controlled release of terbinafine from the functionalized textiles was evaluated against different mimetic biologic solutions (PBS buffer-pH = 7.4, micellar solution and acidic sweat solution-pH = 4.3). The modification of keratin with polyethylene glycol (PEG) moieties favored the release of terbinafine at the end of 48 h for all the solution conditions. When the activity of functionalized textiles was tested against Trichophyton rubrum, a differentiated inhibition was observed. Textiles functionalized with 80% keratin/20% keratin-PEG encapsulating terbinafine showed a 2-fold inhibition halo compared with the textiles containing 100% keratin-encapsulating terbinafine. No activity was observed for the textiles functionalized with keratin-based particles without terbinafine. The systems herein developed revealed therapeutic potential towards nail fungal infections, taking advantage of keratin-based particles affinity to keratin structures and of the keratinase activity of T. rubrum.

Design, Formulation, and Characterization of Valsartan Nanoethosomes for Improving Their Bioavailability

The objective of this study was to formulate and evaluate valsartan (VLT) ethosomes to prepare an optimized formula of VLT-entrapped ethosomes that could be incorporated into a sustained release transdermal gel dosage form. The formulation of the prepared ethosomal gel was investigated and subjected to in vitro drug release studies, ex vivo test, and in vivo studies to assess the effectiveness of ethosomal formulation in enhancing the bioavailability of VLT as a poorly soluble drug and in controlling its release from the transdermal gel dosage form. The acquired results are as follows: Dependent responses were particle size, polydispersity index, zeta potential, and entrapment efficiency. The optimized VLT-ETHs had a nanometric diameter (45.8 ± 0.5 nm), a negative surface charge (-51.4 ± 6.3 mV), and a high drug encapsulation (94.24 ± 0.2). The prepared VLT ethosomal gel (VLT-ethogel) showed a high peak plasma concentration and enhanced bioavailability in rats compared with the oral solution of valsartan presented in the higher AUC (0-∞). The AUC (0-∞) with oral treatment was 7.0 ± 2.94 (μg.h/mL), but the AUC (0-∞) with topical application of the VAL nanoethosomal gel was 137.2 ± 49.88 (μg.h/mL), providing the sustained release pattern of VLT from the tested ethosomal gel.

Novel Hyaluronic Acid ethosomes based gel formulation for topical use with reduced toxicity, better skin permeation, deposition, and improved pharmacodynamics

Hyaluronic Acid (HA) has been applied as an anti-ageing molecule in the form of topical products. Current topical commercial formulations of HA face the limitations of very small and stagnant skin permeation, thereby demanding enduring administration of the formulation to sustain its action. In this study, Lipid-based nanocarriers in the form of ethosomes were formulated in a 1% w/w HA strength and were extensively evaluated in vitro, ex-vivo, and in vivo parameters along with a comparison to it's commercial counterpart. The optimised ethosomes-based HA gel formulation revealed required pH (6.9 ± 0.2), small globule size (1024 ± 9 nm), zeta potential of -6.39 ± 0.2 mV, and 98 ± 1.1% HA content. The ex vivo skin permeation and deposition potenwere conferred on synthetic membrane Strat-M, Human cadaver skin, mice skin, rat skin, and pig skin, and both parameters were found to be much higher in comparison to the commercial topical formulation. Skin deposition capacity of the optimised HA formulation was further confirmed by Scan Electron Microscopy (SEM) and Confocal Laser Scanning Microscopy (CLSM) and it was observed that the developed ethosomal gel formulation got deposited more on the treated skin. The in vivo anti-ageing effect of optimised ethosomal gel on rats was found to be greater when compared to commercial formulation of HA and the developed carrier-based system proved to deliver the HA molecule in very small amounts into the systemic circulation. The results endorse the ethosomal carrier-based formulation of HA as a attractive technique for better local bioavailability of HA.

Metformin-loaded ethosomes with promoted anti-proliferative activity in melanoma cell line B16, and wound healing aptitude: Development, characterization and in vivo evaluation

The present work deals with the development of metformin-loaded ethosomes for localized treatment of melanoma and wound healing. Different ethosomal formulations were prepared using different concentrations of ethanol adopting injection technique. The developed formulations were investigated for entrapment efficiency, ex-vivo skin permeation, vesicle size, morphology and permeation kinetics. The optimized formulation was loaded in 5 % carbomer gel that was evaluated for skin permeation, cytotoxic effect against melanoma mice B16 cell line and for wound healing action. Ethosomes having 30 % v/v ethanol displayed superior entrapment for metformin % (55.3±0.07) ; and a highly efficient permeation via mice skin (85.8±3.7). The related carbomer ethosomal gel exhibited higher skin permeation compared to the untreated metformin gel (P < 0.001). The metformin ethosomes had a substantial antiproliferative activity against melanoma B16 cells compared to corresponding metformin solution as shown by the lower IC50 values (56.45±1.47 and 887.3±23.2, respectively, P<0.05) and tumour cell viability (P<0.05). The ethosomal system had a significant wound healing action in mice (80.5±1.9%) that was superior to that of the marketed product Mebo® ointment (56±1 %), P<0.05. This ethosomal system demonstrated outstanding induction of the mRNA levels of growth factors (IGF-1, FGF-1, PDGF-B and TGF-β) that are essential in the healing process. Those findings were supported by histopathologic examination of wound sections of different treated groups. Thus, the study proved that metformin ethosomes as a promising drug delivery system and a conceivable therapeutic approach for treatment of melanoma and wound healing.

Transcutaneous tumor vaccination combined with anti-programmed death-1 monoclonal antibody treatment produces a synergistic antitumor effect

Transcutaneous immunization (TCI) has the advantages of safety, high efficiency, non-invasiveness and convenient use. The key for a TCI system is transdermal targeted delivery of antigen to dendritic cells (DCs), the most powerful antigen presenting cells. DCs also play an important role in tumor immunotherapy, which provides a huge imagination for the application of TCI to tumor treatment. In this study, a transcutaneous tumor vaccine (TTV) delivery system was developed using the electrospun silk fibroin (SF) and polyvinyl alcohol (PVA) composite nanofibrous patch loaded with mannosylated polyethyleneimine (PEI^man)-modified ethosome (Eth) (termed Eth-PEI^man). Eth-PEI^man showed a good performance in targeting DCs, and the carriers loaded with antigen (encapsulated in Eths) and adjuvant (absorbed in PEI^man) were observed effectively induce DCs maturation in vitro. With the tyrosinase-related protein-2 (TRP2) peptide as antigen and oligodeoxynucleotides containing unmethylated CpG motifs as adjuvant, the TTV-loaded patches (TTVP) significantly inhibited the growth of melanoma in a syngeneic mouse model for melanoma by subcutaneous injection of B16F10 cell lines. Moreover, the combined application of the TTVP and anti-programmed death-1 monoclonal antibody (aPD-1) produced a synergistic antitumor effect, which could be related to the infiltration of more CD4⁺ and CD8⁺ T cells in the tumor tissues. The application of TTVP also increased the expression of IL-12, which may be part of the mechanism of synergistic antitumor effect between the TTVP and aPD-1. These results suggest that the combination of the TTVP and immune checkpoint blockers could be an effective strategy for tumor treatment. STATEMENT OF SIGNIFICANCE: Transcutaneous immunization has the advantages of safety, high efficiency, non-invasiveness and convenient use. In this study, a novel transcutaneous tumor vaccine patch (TTVP) was developed using tumor antigens-loaded ethosomes that can target dendritic cells percutaneously. Our data demonstrated that the TTVP can significantly inhibit tumor growth. Furthermore, the combination of TTVP and aPD-1 produced a synergistic anti-melanoma effect. Considering its convenience and non-invasiveness, this TTVP system could find good application prospects in immunotherapy. The combination of TTVP and aPD-1 could be a useful strategy for the prevention and treatment of tumors.

Lipid-Based Nanovesicular Drug Delivery Systems

In designing a new drug, considering the preferred route of administration, various requirements must be fulfilled. Active molecules pharmacokinetics should be reliable with a valuable drug profile as well as well-tolerated. Over the past 20 years, nanotechnologies have provided alternative and complementary solutions to those of an exclusively pharmaceutical chemical nature since scientists and clinicians invested in the optimization of materials and methods capable of regulating effective drug delivery at the nanometer scale. Among the many drug delivery carriers, lipid nano vesicular ones successfully support clinical candidates approaching such problems as insolubility, biodegradation, and difficulty in overcoming the skin and biological barriers such as the blood-brain one. In this review, the authors discussed the structure, the biochemical composition, and the drug delivery applications of lipid nanovesicular carriers, namely, niosomes, proniosomes, ethosomes, transferosomes, pharmacosomes, ufasomes, phytosomes, catanionic vesicles, and extracellular vesicles.

Formulation development and in vitro-in vivo assessment of protransfersomal gel of anti-resorptive drug in osteoporosis treatment

Osteoporosis is a major cause of morbidity, mortality, and economic burden worldwide. Despite being an effective in combating the bone-deteriorating disorders, bisphosphonates have several shortcomings including poor and variable bioavailability, low permeability, high toxicity, etc. In this study, we developed and optimized protransfersome formulation for the drug risedronate sodium (RIS-Na) with the goal of enhancing its bioavailability and hence patient compliance. Phase separation coacervation technique was utilized for development of optimized formulation. Optimization was achieved by using three-factor, three-level Box-Behnken design combined with Response Surface Methodology (RSM). This enabled us to decipher the effect of 3 independent variables (Phospholipid, Tween-80 and Sodium Deoxycholate) on three dependent parameters (entrapment efficiency, vesicle size and transdermal flux). Optimized formulation was further evaluated for pharmacokinetic and pharmacodynamic parameters. Smooth, spherical protransfersomes with a size of 260 ± 18 nm, having entrapment efficiency and flux of 80.4 ± 4.90% and 8.41 ± 0.148 μg/cm²/h, respectively were prepared. Ex vivo studies revealed a shorter lag time of 1.21 ± 0.18 h and higher flux associated with transdermal formulation. CLSM analysis further revealed better drug penetration (220 μm) through the skin in case of protransfersomes as compared to drug solution (72 μm). Additionally, biomechanical, biochemical, and histo-pathological studies further validated the results. Thus, it was concluded that protransfersome formulation has a great potential in providing better therapeutic efficacy of risedronate than its conventional counterpart.

Constant Voltage Iontophoresis Technique to Deliver Terbinafine via Transungual Delivery System: Formulation Optimization Using Box-Behnken Design and In Vitro Evaluation

Topical therapy of antifungals is primarily restricted due to the low innate transport of drugs through the thick multi-layered keratinized nail plate. The objective of this investigation was to develop a gel formulation, and to optimize and evaluate the transungual delivery of terbinafine using the constant voltage iontophoresis technique. Statistical analysis was performed using Box–Behnken design to optimize the transungual delivery of terbinafine by examining crucial variables namely concentration of polyethylene glycol, voltage, and duration of application (2–6 h). Optimization data in batches (F1–F17) demonstrated that chemical enhancer, applied voltage, and application time have influenced terbinafine nail delivery. Higher ex vivo permeation and drug accumulation into the nail tissue were noticed in the optimized batch (F8) when compared with other batches (F1–F17). A greater amount of terbinafine was released across the nails when the drug was accumulated by iontophoresis than the passive counterpart. A remarkably higher zone of inhibition was observed in nails with greater drug accumulation due to iontophoresis, as compared to the passive process. The results here demonstrate that the optimized formulation with low voltage iontophoresis could be a viable and alternative tool in the transungual delivery of terbinafine, which in turn could improve the success rate of topical nail therapy in onychomycosis.

Nanostructured Ethosomal Gel Loaded with Arctostaphylos uva-ursi extract; In-vitro/In-vivo Evaluation as a Cosmeceutical Product

BACKGROUND

Arctostaphylos uva-ursi (AUU) being rich in polyphenols and arbutin is known to have promising biological activities and can be a potential candidate as a cosmaceutical. Ethosomes encourage the formation of lamellar-shaped vesicles with improved solubility and entrapment of many drugs including plant extracts.

OBJECTIVE

The objective of this work was to develop an optimized nanostructured ethosomal gel formulation loaded with AUU extract and evaluated for skin rejuvenation and depigmentation.

METHODS

AUU extract was tested for phenolic and flavonoid content, radical scavenging potential, reducing power activity, and in-vitro SPF (sun protection factor) estimation. AUU loaded 12 formulations were prepared and characterized by SEM (scanning electron microscopy), vesicular size, zeta potential, and entrapment efficiency (%EE). The optimized formulation was subjected to non-invasive in-vivo investigations after incorporating it into the gel system and ensuring its stability and skin permeation.

RESULTS

Ethosomal vesicles were spherical in shape and Zeta size, zeta potential, PDI (polydispersity index), % EE and in-vitro skin permeation of optimized formulation (F3) were found to be 114.7nm, -18.9mV, 0.492, 97.51±0.023%, and 79.88±0.013% respectively. AUU loaded ethosomal gel formulation was stable physicochemically and exhibited non-Newtonian behavior rheologically. Moreover, it significantly reduced skin erythema, melanin as well as sebum level and improved skin hydration and elasticity.

CONCLUSION

A stable AUU based ethosomal gel formulation could be a better vehicle for phytoextracts than conventional formulations for cosmeceutical applications such as for skin rejuvenation and depigmentation etc.

Ethosomes as Nanocarriers for the Development of Skin Delivery Formulations

The use of nanotechnology has been extensively explored for developing efficient drug delivery systems towards topical and transdermal applications. Ethosomes constitute a vesicular nanocarrier containing a relatively high concentration of ethanol (20-45%). Ethanol is a well-known permeation enhancer, which confers ethosomes unique features, including high elasticity and deformability, allowing them to penetrate deeply across the skin and enhance drug permeation and deposition. The improved composition of ethosomes offer, thereby, significant advantages in the delivery of therapeutic agents over particularly the conventional liposomes regarding different pathologies, including acne, psoriasis, alopecia, skin infections, hormonal deficiencies, among others. This review provides a comprehensive overview of the ethosomal system and an assessment of its potential as an efficient nanocarrier towards the skin delivery of active ingredients. Special attention is given to the composition of ethosomes and the mechanism of skin permeation, as well as their potential applications in different pathologies, particularly skin pathologies (acne, psoriasis, atopic dermatitis, skin cancer and skin infections). Some examples of ethosome-based formulations for the management of skin disorders are also highlighted. Besides the need for further studies, particularly in humans, ethosomal-based formulations hold great promise in the skin delivery of active ingredients, which increasingly asserts oneself as a viable alternative to the oral route.

A Newfangled Collagenase Inhibitor Topical Formulation Based on Ethosomes with Sambucus nigra L. Extract

Sambucus nigra L. (S. nigra) is a shrub widespread in Europe and western Asia, traditionally used in medicine, that has become popular in recent years as a potential source of a wide range of interesting bioactive compounds. The aim of the present work was to develop a topical S. nigra extract formulation based on ethosomes and thus to support its health claims with scientific evidence. S. nigra extract was prepared by an ultrasound-assisted method and then included in ethosomes. The ethosomes were analyzed in terms of their size, stability over time, morphology, entrapment capacity (EC), extract release profile, stability over time and several biological activities. The prepared ethosomes were indicated to be well defined, presenting sizes around 600 nm. The extract entrapment capacity in ethosomes was 73.9 ± 24.8%, with an interesting slow extract release profile over 24 h. The extract-loaded ethosomes presented collagenase inhibition activity and a very good skin compatibility after human application. This study demonstrates the potential use of S. nigra extract incorporated in ethosomes as a potential cosmeceutical ingredient and on further studies should be performed to better understand the impact of S. nigra compounds on skin care over the time.

Central composite design for the development of carvedilol-loaded transdermal ethosomal hydrogel for extended and enhanced anti-hypertensive effect

Background

Carvedilol, the anti-hypertensive drug, has poor bioavailability when administered orally. Ethosomes-mediated transdermal delivery is considered a potential route of administration to increase the bioavailability of carvedilol. The central composite design could be used as a tool to optimize ethosomal formulation. Thus, this study aims to optimize carvedilol-loaded ethosomes using central composite design, followed by incorporation of synthesized ethosomes into hydrogels for transdermal delivery of carvedilol.

Results

The optimized carvedilol-loaded ethosomes were spherical in shape. The optimized ethosomes had mean particle size of 130 ± 1.72 nm, entrapment efficiency of 99.12 ± 2.96%, cumulative drug release of 97.89 ± 3.7%, zeta potential of − 31 ± 1.8 mV, and polydispersity index of 0.230 ± 0.03. The in-vitro drug release showed sustained release of carvedilol from ethosomes and ethosomal hydrogel. Compared to free carvedilol-loaded hydrogel, the ethosomal gel showed increased penetration of carvedilol through the skin. Moreover, ethosomal hydrogels showed a gradual reduction in blood pressure for 24 h in rats.

Conclusions

Taken together, central composite design can be used for successful optimization of carvedilol-loaded ethosomes formulation, which can serve as the promising transdermal delivery system for carvedilol. Moreover the carvedilol-loaded ethosomal gel can extend the anti-hypertensive effect of carvedilol for a longer time, as compared to free carvedilol, suggesting its therapeutic potential in future clinics.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-021-00833-4.

Ethosomal Gel Formulation of Alpha Phellandrene for the Transdermal Delivery in Gout

Purpose: Purpose was to improve the skin compatibility and permeability of alpha phellandrene through an ethosomal gel formulation for the treatment of gout; as the oral use of the drug is reported to cause gastrointestinal disturbances and toxicities.

Methods: Alpha phellandrene loaded ethosomal formulation (APES) was prepared by cold method for the treatment of gout. APES were loaded into carbopol gel (APEG) by dispersion method. Physico-chemical characterizations of the APES were done by dynamic light scattering (DLS), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR) etc. In vitro release, permeation, haemo-compatibility and anti-inflammatory studies were conducted.

Results: APES showed a particle size of 364.83 ± 45.84 nm. The entrapment efficiency of the optimized formulation is found as 95.06 ± 2.51%. Hemolysis data indicated that APES does not cause any significant hemolysis. In vitro drug release studies were carried out using dialysis membrane technique and the amount of drug released from APES & APEG is found to be 95% and 94.21% respectively after 5 and6 hours. Kinetic data analysis revealed that APES & APEG follows first order and zero order release kinetics, respectively. The anti-inflammatory activity studies of the formulation are done by estimating its inhibitory effects on cyclooxygenase II (COX) II, lipoxygenase-5 (LOX-5), Myeloperoxidase (MPO), Inducible nitric oxide synthase (INOS) & cellular nitrite level using RAW 264.7 cells. The significant inhibition in the activities of the enzymes implies the anti-inflammatory activity of the formulations. Skin permeation study was carried out using porcine skin and revealed that the permeation of alpha phellandrene is increased from APES & APEG when compared with alpha-phellandrene solution (APS). Skin deposition study of APS, APES & APEG revealed better drug deposition from APEG (48.799 ± 1.547µg/cm² ) after 24 hours when compared with APS & APES.

Conclusion: Overall results indicate that the ethosomal formulation of alpha phellandrene through transdermal route is an effective alternative for oral use of the drug.

Effect of Different Nail Penetration Enhancers in Solid Lipid Nanoparticles Containing Terbinafine Hydrochloride for Treatment of Onychomycosis

Onychomycosis is considered a stubborn nail fungal infection that does not respond to conventional topical antifungal treatments. This study aimed to develop and characterize novel solid lipid nanoparticles (SLNs) formulae containing terbinafine HCl (TFH) and loaded with different nail penetration enhancers (nPEs). Three (nPEs) N-acetyl-L-cysteine, thioglycolic acid, and thiourea were used. Characterization of the prepared formulae was done regarding particle size, zeta potential, polydispersity index (PDI), entrapment efficiency (EE%), physical stability, in vitro release study, infrared (FT-IR), and their morphological structures. The selected formulae and the marketed cream Lamifen® were compared in terms of their antifungal activity against Trichophyton rubrum as well as their nail hydration and their drug uptake by the nail clippers. Thiourea was the nPE of choice; formulae (N2 and N8), with thiourea, were considered the optimum TFH SLNs containing nPEs. They were selected for their optimum particle size of 426.3 ± 10.18 and 450.8 ± 11.45 nm as well as their highest EE% of 89.76 ± 1.25 and 90.35 ± 1.33, respectively. The in vitro microbiological screening of the antifungal activity of these two formulae showed significantly larger zones of inhibition in comparison with the marketed product. The ex vivo screening of the drug uptake of the two selected formulae was significantly higher than that of the marketed product. The nPE formulae present a very promising option as they showed optimum physicochemical characterization with high antifungal activity and high drug uptake as well as good nail hydration effect.

Quality by design (Qbd) assisted development of phytosomal gel of aloe vera extract for topical delivery

The aim of the current study was to develop the phytosomal gel of aloe vera extract for improved topical delivery. Aloe vera extract loaded phytosomal system was developed by fixing the amount of aloe vera extract and ethanol and by varying the concentration of lecithin (0.15-0.25% w/v) and speed of rotation (80-120 rpm). Different formulation batches were prepared as per the Design expert software. A 2² Factorial design was applied to optimize the formulation on the basis of vesicular size and entrapment efficiency. Developed formulations were evaluated for vesicular size, entrapment efficiency, PDI, zeta potential and in-vitro release. Further stability studies were also performed. For the optimized formulation (F09), vesicular size, entrapment efficiency and PDI were found as 123.1 ± 1.44 nm, 95.67 ± 0.27% and 0.98 ± 0.06. Zeta potential of -11.9 mV and drug release of 56.91 ± 4.1% obtained in 24 h. Drug release kinetics from the phytosomes follows Higuchi model. TEM micrograph confirms the uniform structure of phytosomes. Phytosomal gel of optimized phytosomal formulation (F09) was developed with 1% Carbopol 934 and physically characterized on the basis of pH, viscosity, homogeneity and drug content. Ex-vivo permeation study showed the better permeation and flux profile of phytosomal gel with the conventional aloe vera extract gel. Also, studies on phytosomal formulation and gel showed stability up-to 3 months. Thus overall, it can be concluded that the phytosomal gel is a good carrier for topical delivery of herbal extract such as aloe vera.

Exploration of Nanoethosomal Transgel of Naproxen Sodium for the Treatment of Arthritis

BACKGROUND

The present work aimed to develop an ethosomal gel of naproxen sodium for the amelioration of rheumatoid arthritis.

OBJECTIVE

In the present work, we have explored the potential of ethosomes to deliver naproxen into deeper skin strata. Further, the anti-inflammatory efficacy of naproxen ethosomal formulation was assessed using the carrageenan-induced rat paw edema model.

METHODS

Naproxen sodium nanoethosomes were prepared using different proportions of lipoid S100 (50mg-200mg), ethanol (20-50%) and water, and were further characterized on the basis of vesicle morphology, entrapment efficiency, zeta potential, in-vitro drug release and ex-vivo permeation studies.

RESULTS

The optimized ethosomal formulation was found to have 129 ± 0.01 nm particle size, 0.295 Polydispersity Index (PDI), -3.29 mV zeta potential, 88% entrapment efficiency and 96.573% drug release in 24 hours. TEM and SEM analysis of the optimized formulation showed slightly smooth spherical structures. The Confocal laser scanning microscopy showed that ethosomes could easily infiltrate into deeper dermal layers (upto 104.9μm) whereas the hydroalcoholic solution of the drug could penetrate up to 74.9μm. Further, the optimized ethosomal formulation was incorporated into 1% carbopol 934 gel base and optimized wherein the transdermal flux was found to be approximately 10 times more than the hydroethanolic solution. Also, the in-vivo pharmacodynamic study of the optimized ethosomal gel exhibited a higher percentage inhibition of swelling paw edema than marketed diclofenac gel.

CONCLUSION

The ethosomal gel was successfully developed and has shown the potential to be a good option for the replacement of conventional therapies of rheumatoid arthritis.

A Comparative Formulation Development and Evaluation of Tazarotene Ethosomal and Transfersomal Gel for Effective Management of Acne

Acne vulgaris is the most prevalent disorder in the period before puberty when increased adrenal androgen level causes enlargement of the sebaceous glands and it increased the production of sebum on the face, chest, and back. This disease is caused due to interaction between many causative agents or pathogenic components which lead to formation of the acne and those are seborrhea, follicular hyper keratinization, microbial formation of pilosebaceous unit by Propionibacterium acne and arrival of inflammatory mediators. Tazarotene is a well-known retinoid related to vitamin A that belongs to an acetylenic class of retinoid, used in the management of acne. Oral administration of Tazarotene causes changes in bone morphology after prolonged exposure to high doses, which also exhibit teratogenicity but this does not occur with topical delivery. Ethosomes are non-invasive delivery carriers enabling drugs to reach to the bottom of the skin layers and/or the system and transfersomes are the self-adaptable ultra-deformable flexible elastic bilayer vesicles composed of phospholipids able to penetrate through the pores of skin even smaller than its size. Present research aims the comparative evaluation of ethosomal and transfersomal gels loaded with Tazarotene in the treatment of acne. In the present study, ethosomes and transfersomes were formulated by the cold method and hand-shaking method, respectively, followed by loading of Tazarotene and development into gel formulation. The formulated gel samples were evaluated for in vitro release study, in vitro permeation study, in vitro anti-acne study, in vivo percutaneous permeation study by CLSM, and in vivo anti-acne study. The results proved that both the formulated ethosomal and transfersomal gels have better permeation through the skin but ethosomal gel showed better release in comparison to transfersomal gel, also final gels exhibited the anti-acne potentiality.

Ethosome-Derived Invasomes as a Potential Transdermal Delivery System for Vardenafil Hydrochloride: Development, Optimization and Application of Physiologically Based Pharmacokinetic Modeling in Adults and Geriatrics

Aim

The aim of the current work was to develop vardenafil hydrochloride (VRD)-loaded ethosome-derived invasomes as a possible transdermal system which could be used for patients suffering from pulmonary arterial hypertension.

Methods

VRD-loaded ethosomes were developed at three concentrations of phosphatidylcholine (5, 10 and 15 mg/mL) and three percentages of ethanol (20%, 30% and 40%, v/v). The best achieved VRD-loaded ethosomes (ETH9) were optimized to invasomes via incorporation of terpenes (limonene, cineole and a 1:1 mixture) at three concentrations (0.5%, 1% and 2%, v/v). All systems were evaluated for vesicle size, zeta potential, drug entrapment efficiency (EE%), cumulative drug permeated percentages after 0.5hrs (Q_0.5h) and 12hrs (Q_12h) and steady-state flux (J_ss). The optimized system (ETH9-INV8) was further characterized for morphology, histopathology and confocal laser scanning microscopy (CLSM). Physiologically based pharmacokinetic (PBPK) modeling was employed to estimate VRD pharmacokinetic parameters from the optimized transdermal system and an oral aqueous drug dispersion, in adults and geriatrics.

Results

The optimized invasomal system (ETH9-INV8) was characterized with spherical vesicles (159.9 nm) possessing negative zeta potential (-20.3 mV), promising EE% (81.3%), low Q_0.5h (25.4%), high Q_12h (85.3%) and the largest steady-state flux (6.4 µg.cm^-2h^-1). Following a leave-on period of 12hrs in rats, it showed minor histopathologic changes. CLSM studies proved its ability to deeply permeate rat skin. Lower C_max values, delayed T_max estimates and greater AUC_0-24h folds in adults and geriatrics (≈ 2.18 and 1.69, respectively) were estimated following the transdermal application of ETH9-INV8 system.

Conclusion

ETH9-INV8 is a promising transdermal system for VRD.

Topical Delivery of Four Neuroprotective Ingredients by Ethosome-Gel: Synergistic Combination for Treatment of Oxaliplatin-Induced Peripheral Neuropathy

Background

Peripheral neuropathy is a common and painful side effect that occurs in patients with cancer induced by Oxaliplatin (OXL). The neurotoxicity correlates with the damage of dorsal root ganglion (DRG) neurons and Schwann cells (SCs). Hydroxysafflor yellow A (HSYA), icariin, epimedin B and 3, 4-dihydroxybenzoic acid (DA) are the main neuroprotective ingredients identified in Wen-Luo-Tong (WLT), a traditional Chinese medicinal topical compound. The purpose of this study was to prepare and evaluate the efficacy of an ethosomes gel formulation loaded with a combination of HSYA, icariin, epimedin B and DA. However, the low LogP value, poor solubility and macromolecule are several challenges for topical delivery of these drugs.

Methods

Ethosomes were prepared by the single-step injection technique. Particle size, entrapment efficiency and in vitro drug deposition studies were determined to select the optimum ethosomes. The optimized ethosomes were further incorporated into carbopol to obtain a gel. The rheological properties, morphology, in vitro drug release, in vitro gel application and skin distribution of the ethosomes gels were studied. A rat model of oxaliplatin-induced neuropathy was established to assess the therapeutic efficacy of the ethosomes gel.

Results

Seventy percent (v/v) ethanol, cinnamaldehyde and Phospholipon 90G were employed to develop ethosomes a carrier system. This system had a high entrapment efficiency, carried large amounts of HSYA, epimedin B, DA and icarrin, and penetrated deep into the epidermis and dermis. The optimized ethosomes had the maximum deposition of icariin, HSYA, epimedin B and relative higher amount of DA in epidermis (2.00±0.13 µg/cm², 5.72±0.75 µg/cm², 1.97±0.27 µg/cm² and 9.25±1.21 µg/cm², respectively). 0.5% carbopol 980 was selected to develop the ethosomes gel with desirable viscoelasticity and spreadability, which was suitable for topical application. The mechanical allodynia and hyperalgesia induced by OXL in rats were significantly reduced after the new ethosomes gel was applied to rats compared to model group.

Conclusion

Based on our findings, the ethosomes gel delivery system provided a new formulation for the topical delivery of HSYA, icariin, epimedin B and DA to counteract OXL-induced peripheral neuropathy.

Topical photodynamic therapy of tumor bearing mice with meso-tetrakis (N-methyl-4-pyridyl) porphyrin loaded in ethosomes

Photodynamic therapy is a clinically approved procedure for the treatment of neoplastic and other non-malignant diseases. Meso-tetrakis(N-methyl-4-pyridyl)porphyrin (TMPyP) is a photosensitizing agent which has been used in many applications. However, the use of TMPyP topically is limited due to its hydrophilicity. To overcome this problem, TMPyP was loaded in ethosomes. Three ethosomal formulae (A), (B) and (C) were prepared and characterized. Preparation (A) was chosen to be used in the in vitro and in vivo study, having the greatest encapsulation efficiency, the smallest size and the highest cumulative release percentage. The results of in vitro permeation study revealed that the ethosomal TMPyP was superior to the drug in the free form with permeation flux (3.92 μg cm^-2 h^-1). In the in vivo animal study done on Swiss albino mice, after 19 days of Ehrlich tumor implantation, the group treated with the ethosomal preparation showed significantly smaller tumor size (143.28 ± 13.2 mm³) compared to the group treated with the free TMPyP (219 ± 11.9 mm³). It showed also significant longer survival time (21 days) compared to that treated with the free drug (18.2 ± 1.2 days). Based on the obtained results, transdermal delivery of TMPyP was potentiated by incorporating it in ethosomes.

Development and in-vitro evaluation of co-loaded berberine chloride and evodiamine ethosomes for treatment of melanoma

Berberine chloride (BBR) and evodiamine (EVO) are two main active ingredients of "ZuoJinWan", a classical Chinese herbal medicine, and these compounds are known to have a synergistic inhibitory effect on various cancer cell lines. Several recent studies have reported anti-melanoma effects for both BBR and EVO. However, topical delivery of the two compounds has been challenging, due to their poor aqueous solubility and their low skin penetration. In the current study, we have combined BBR and EVO into an ethosomes delivery system with the future aim to design a novel topical anti-melanoma formulation. The ethosomes formulations were characterized using particle size, entrapment efficiency and an in vitro skin drug deposition study. The ethosome formulation displaying maximum drug deposition in the epidermis was selected for further study. This formulation contained ethosomes with mean size of 171 nm and 90% or above entrapment efficiency for both BBR and EVO. Cell viability tests proved the optimized ethosomes increased the inhibitory effect on B16 melanoma cells. These results corroborate that ethosomes containing a combination of BBR and EVO are a promising delivery system for potential use in melanoma therapy.

Dermal Targeting Delivery of Terbinafine Hydrochloride Using Novel Multi-Ethosomes: A New Approach to Fungal Infection Treatment

This research aimed to develop and evaluate a novel multi-ethosome (ME) system for the dermal delivery of terbinafine hydrochloride (TH) as a new approach to fungal infection treatment. TH-loaded MEs were successfully prepared using cinnamaldehyde as a penetration enhancer. Mean diameter of ME was found as ~100 nm with monodispersed size distribution. Drug entrapment efficiency reached up to 86% ± 1.4%. MEs exhibited excellent colloid stability and no drug leakage after 2 months of storage. In contrast to a commercial Lamisil® cream, ME significantly improved the targeting efficiency by increasing the fluidity of stratum corneum layer, revealed by attenuated total reflection Fourier transformed infrared spectroscopy (ATR-FTIR). The dermal targeting effect was visualized using confocal microscopy. Moreover, skin irritation and allergy tests showed that ME was not irritating to the skin. The improved antifungal activity of ME was proved in vitro on Candida albicans strains by minimal inhibitory concentration (MIC) assay. This study paves the way towards design of MEs for dermal fungal infection treatment.

Development and optimization of nanoemulsion based gel for enhanced transdermal delivery of nitrendipine using box-behnken statistical design

Objective: The purpose of present research was to develop and statistically optimize nitrendipine nanoemulsion gel for transdermal delivery using box-behnken statistical design.Method: The nanoemulsion formulations bearing nitrendipine were prepared by application of ternary phase diagram and spontaneous emulsification method. Box-behnken design was employed for the optimization of nitrendipine loaded nanoemulsion. The independent variables were oil, surfactant and co-surfactant while globule size, drug content and zeta potential were dependent variables. The optimized nanoemulsion formulation was incorporated into gel and evaluated for in-vitro release, ex-vivo permeation studies, confocal laser scanning microscopy, skin irritation and histopathological studies.Results: The optimized formulation through box-behnken statistical design showed globule size of 20.43 ± 1.50 nm, drug content of 97.05 ± 1.77% and zeta potential of -15.45 ± 0.35 mV. The ex-vivo study confirmed the enhanced delivery of nitrendipine from nanoemulsion gel than compare to drug solution by virtue of better permeation and solubility. Nanoemulsion gel was proved significantly superior by confocal laser scanning microscopy for satisfactory permeation and distribution of gel, deep into the rat skin. The optimized gel was found with no allergic dermal effects and was proved safe by histopathological studies for transdermal application.Conclusions: Results reveals that developed nitrendipine nanoemulsion gel overcomes the limitation of low penetration and accentuate permeation through albino Wistar rat skin. It was concluded that nanoemulsion gel could be utilized as a potential carrier for transdermal delivery of nitrendipine.

Formulation and Characterization of Nanosized Ethosomal Formulations of Antigout Model Drug (Febuxostat) Prepared by Cold Method: In Vitro/Ex Vivo and In Vivo Assessment

Febuxostat (FXT) is a xanthine oxidase (XO) drug which indicated for the treatment of gout. FXT loaded nanosized ethosomes were prepared using cold method with varied concentrations of ethyl alcohol and soya lecithin (SL). The prepared ethosomes were characterized by size, entrapment efficiency (DEE), FT-IR, in vitro release, kinetic studies of in vitro release profile, in vitro skin permeation and deposition, and stability study. The selected ethosomal formulation was incorporated in HPMC gel and characterized for drug content, ex vivo diffusion study through rat skin, and in vivo study and determination of pharmacokinetic parameters using HPLC technique. The results of size analysis showed that minimum size was 124.2 ± 16.77 nm with PDI values between 0.2 and 0.6. The zeta potential was from - 43.5 ± 3.0 to - 20.6 ± 1.42 mV. DEE ranged from 48 to 86%. The results of in vitro skin permeation showed that the amount FXT permeated ranged from 43.33 ± 5.3 to 82.14 ± 5.8%, flux ranged from 14.85 to 28.02. The results of ex vivo study showed that the amount of FXT permeated from unprocessed FXT gel was 49.42 ± 3.29% which was lesser than from FXT ethosomal gel. The results of in vivo study showed that C_max and t_max were significantly different and higher for transdermal administration of FXT than oral administration. The developed FXT nanosized selected ethosome-based transdermal drug delivery gel system would provide a promising method for better management of gout.

Mechanism of transdermal permeation promotion of lipophilic drugs by ethosomes

Ethosomes can promote the penetration of lipophilic drugs into the skin, but the underlying mechanism is still unknown. The purpose of this study was to investigate the mechanism of transdermal permeation promotion of lipophilic drugs by ethosomes. The formulation of ethosomes was optimized using the Box-Behnken experimental design, in which Rhodamine B and 1-palmitoyl-2-{12-[(7-nitro-2-1,3-benzoxadiazol-4-yl)amino]dodecanoyl}-sn-glycero-3-phosphocholine were used to simulate a model lipophilic drug and act as a fluorescent tracer of ethosomal phospholipids, respectively. Liposomes with the same phospholipid concentration and a hydroethanolic solution with the same ethanol concentration were also prepared as controls. The percutaneous progression of the above fluorescent preparations was observed by confocal laser scanning microscopy, and the fluorescence intensity of the images was analyzed. The optimized ethosome formulation consisted of 2.45% yolk phospholipids, 30% ethanol, and 67.55% distilled water. The percutaneous permeation of Rhodamine B in the optimized ethosomes was superior to that in hydroethanolic solution (P<0.05) and liposomes (P<0.05). The ethosomes could penetrate the skin via the percutaneous pathway of the hair follicle and stratum corneum, while during the process of penetration, the vesicles were broken and the phospholipids were retained in the upper epidermis, with the test compounds penetrating gradually. The superior percutaneous penetration of ethosomes was linked to the synergistic effects of their ingredients. The percutaneous pathways of ethosomes included open hair follicles and stratum corneum pathways. In addition, the vesicles might break up during percutaneous penetration in the superficial layer of the skin, allowing the test compounds to keep permeating into the deeper layer alone, while the phospholipid was retained in the upper epidermis.