Ethosomes for enhanced skin delivery of griseofulvin

Preparation of Baicalin Liposomes Using Microfluidic Technology and Evaluation of Their Antitumor Activity by a Zebrafish Model

Baicalin (BCL), a well-known flavonoid molecule, has numerous therapeutic applications. However, its low water solubility and bioavailability limit its applicability. Microfluidics is a new method for liposome preparation that provides efficient and rapid control of the process, improving the stability and controllability. This study used microfluidic techniques to create baicalin liposomes (BCL-LPs), first screening for optimal total flow rates (TFR) and flow rate ratios (FRR), and then optimizing the phospholipid concentration, phospholipid-to-cholesterol ratio, and Tween-80 concentration using univariate and response surface methodology approaches. The study found that the ideal phospholipid content was 9.5%, the phospholipid-to-cholesterol ratio was 9:1 (w:w), and the Tween-80 concentration was 15%. BCL-LPs achieved 95.323% ± 0.481% encapsulation efficiency under the optimum circumstances. Characterization indicated that the BCL-LPs were spherical and uniform in size, with a mean diameter of 62.32 nm ± 0.42, a polydispersity index of 0.092 ± 0.009, and a zeta potential of -25.000 mV ± 0.216. In vitro experiments found that BCL-LPs had a better slow-release effect and stability than the BCL monomer. In zebrafish bioassays, BCL-LPs performed better than BCL monomer in terms of biological activity and bioavailability. The established method provided a feasible medicine delivery platform for BCL and could apply for the transport and encapsulation of more natural compounds, expanding the applications of drug delivery systems in healthcare and cancer therapies.

Beyond Skin Deep: Phospholipid-Based Nanovesicles as Game-Changers in Transdermal Drug Delivery

Transdermal administration techniques have gained popularity due to their advantages over oral and parenteral methods. Noninvasive, self-administered delivery devices improve patient compliance and control drug release. Transdermal delivery devices struggle with the skin's barrier function. Molecules over 500 Dalton (Da) and ionized compounds don't permeate through the skin. Drug encapsulation in phospholipid-based vesicular systems is the most effective skin delivery technique. Vesicular carriers include bi-layered liposomes, ultra-deformable liposomes, ethanolic liposomes, transethosomes, and invasomes. These technologies enhance skin drug permeation by increasing formula solubilization, partitioning into the skin, and fluidizing the lipid barrier. Phospholipid-based delivery systems are safe and efficient, making them a promising pharmaceutical and cosmeceutical drug delivery technique. Still, making delivery systems requires knowledge about the physicochemical properties of the drug and carrier, manufacturing and process variables, skin delivery mechanisms, technological advances, constraints, and regulatory requirements. Consequently, this review covers recent research achievements addressing the mentioned concerns.

Chitosan-modified dihydromyricetin liposomes promote the repair of liver injury in mice suffering from diabetes mellitus

Liver injury caused by type-II diabetes mellitus (DM) is a significant public-health concern worldwide. We used chitosan (CS) to modify dihydromyricetin (DHM)-loaded liposomes (DL) through charge interaction. The effect of CS-modified DL (CDL) on liver injury in mice suffering from DM was investigated in vivo and in vitro. CDL exhibited superior antioxidant capacity and stability. Pharmacokinetic analyses revealed a 3.23- and 1.92-fold increase in the drug concentration-time curve (953.60 ± 122.55 ng/mL/h) in the CDL-treated group as opposed to the DHM-treated group (295.15 ± 25.53 ng/mL/h) and DL-treated group (495.31 ± 65.21 ng/mL/h). The maximum drug concentration in blood (Tmax) of the CDL group saw a 2.26- and 1.21-fold increase compared with that in DHM and DL groups. We observed a 1.49- and 1.31-fold increase in the maximum drug concentration in blood (Cmax) in the CDL group compared with that in DHM and DL groups. Western blotting suggested that CDL could alleviate liver injury in mice suffering from DM by modulating inflammatory factors and the transforming growth factor-β1/Smad2/Smad3 signaling pathway. In conclusion, modification of liposomes using CS is a viable approach to address the limitations of conventional liposomes and insoluble drugs.

Novel SmartReservoirs for hydrogel-forming microneedles to improve the transdermal delivery of rifampicin

Hydrogel-forming microneedles (HF-MNs) are composed of unique cross-linked polymers that are devoid of the active pharmaceutical ingredient (API) within the microneedle array. Instead, the API is housed in a reservoir affixed on the top of the baseplate of the HF-MNs. To date, various types of drug-reservoirs and multiple solubility-enhancing approaches have been employed to deliver hydrophobic molecules combined with HF-MNs. These strategies are not without drawbacks, as they require multiple manufacturing steps, from solubility enhancement to reservoir production. However, this current study challenges this trend and focuses on the delivery of the hydrophobic antibiotic rifampicin using SmartFilm-technology as a solubility-enhancing strategy. In contrast to previous techniques, smart drug-reservoirs (SmartReservoirs) for hydrophobic compounds can be manufactured using a one step process. In this study, HF-MNs and three different concentrations of rifampicin SmartFilms (SFs) were produced. Following this, both HF-MNs and SFs were fully characterised regarding their physicochemical and mechanical properties, morphology, Raman surface mapping, the interaction with the cellulose matrix and maintenance of the loaded drug in the amorphous form. In addition, their drug loading and transdermal permeation efficacy were studied. The resulting SFs showed that the API was intact inside the cellulose matrix within the SFs, with the majority of the drug in the amorphous state. SFs alone demonstrated no transdermal penetration and less than 20 ± 4 μg of rifampicin deposited in the skin layers. In contrast, the transdermal permeation profile using SFs combined with HF-MNs (i.e. SmartReservoirs) demonstrated a 4-fold increase in rifampicin deposition (80 ± 7 μg) in the skin layers and a permeation of approx. 500 ± 22 μg. Results therefore illustrate that SFs can be viewed as novel drug-reservoirs (i.e. SmartReservoirs) for HF-MNs, achieving highly efficient loading and diffusion properties through the hydrogel matrix.

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.

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.

Preparation and Evaluation of a Microsponge Dermal Stratum Corneum Retention Drug Delivery System for Griseofulvin

Griseofulvin (GF) is used as an antifungal to treat superficial skin fungal infections such as tinea capitis and tinea pedis. Currently, GF is only available in traditional oral dosage forms and suffers from poor and highly variable bioavailability, hepatotoxicity, and long duration of treatment. Therefore, the main objective of this study was to reduce the side effects of the drug and to increase the concentration of the drug retained in the cutaneous stratum corneum (SC) and improve its efficacy through the preparation of drug-laden GF microsponge (GFMS). The emulsification-solvent-diffusion method was used to prepare GFMS, and the prescriptions were screened by a single-factor approach. The optimized formulation (GFF8) had a microsponge particle size (μm) of 28.36 ± 0.26, an encapsulation efficiency (%) of 87.53 ± 1.07, a yield (%) of 86.58 ± 0.42, and drug release (%) from 77.57 ± 3.88. The optimized microsponge formulation was then loaded into a Carbopol 934 gel matrix and skin retention differences between the microsponge gel formulation and normal gels were examined by performing skin retention and fluorescence microscopy tests. Finally, the hepatoprotective and cutaneous stratum corneum retention abilities of microsponge gel formulations compared to oral GF formulations were assessed by hepatotoxicity, pharmacokinetics, and tissue distribution studies. This provides a new perspective on GF dermal stratum corneum retention administration.

Ethosomes as dermal/transdermal drug delivery systems: applications, preparation and characterization

Transdermal drug delivery systems (TDDSs) have gained substantial attention during the last decade. TDDS are versatile delivery systems in which active components are delivered to skin for local effects or systemic delivery of active pharmaceutical through the skin. Overcoming stratum corneum is the most challenging step of delivering drugs through the skin. Lipid-based vesicular delivery systems due to the capability of the delivery of both hydrophilic and hydrophobic drugs are becoming more popular during the recent years. Ethosomes are innovative, biocompatible, biodegradable and non-toxic form of lipid-based vesicles that efficiently enable to entrap drugs of various physicochemical properties. These are other forms of liposome which contain high amounts of ethanol in their structure that enabling ethosomes to efficiently penetrate through deeper layers of skin. Ethosomes have various compositions based on their type but are mainly composed of phospholipids, ethanol, water and the active components. Ethosomes are easily manufactured and they are superior compared to liposomes in terms of different aspects due to the presence of ethanol. The purpose of this review is to thoroughly focus on various aspects of ethosomes, including mechanism of penetration, advantages and disadvantages, characterisation and applications.

In Vitro Skin Delivery of Griseofulvin by Layer-by-Layer Nanocoated Emulsions Stabilized by Whey Protein and Polysaccharides

Griseofulvin is a poorly water-soluble drug administered orally to treat topical fungal infections of the skin and hair. However, oral administration leads to poor and unpredictable drug pharmacokinetics. Additionally, griseofulvin is unstable in the presence of light. A layer-by-layer (LbL) nanocoating approach was employed to curb these shortcomings by stabilizing emulsions, lyophilized emulsions, and reconstituted emulsions with a layer each of whey protein, and either hyaluronic acid, amylopectin, or alginic acid, which captured the drug. The coating materials are biological, environmentally benign, and plentiful. Photostability studies indicated that the LbL particles afforded 6 h of protection of the topical application. In vitro absorption studies showed that griseofulvin concentrated preferentially in the stratum corneum, with virtually no transdermal delivery. Therefore, LbL-nanocoated emulsions, lyophilized particles, and reconstituted lyophilized emulsions can produce a viable topical delivery system to treat superficial fungal infections.

CaCO3-based carriers with prolonged release property for antifungal drug delivery to hair follicles

Superficial fungal infections are of serious concern worldwide due to their morbidity and increasing distribution across the globe in this era of growing antimicrobial resistance. Delivery of antifungals to target...

Development and evaluation of the effect of ethanol and surfactant in vesicular carriers on Lamivudine permeation through the skin

The skin embodies a relatively large and readily accessible surface area to absorb a drug through a non-invasive procedure. The vesicular carrier systems such as liposomes, ethosomes, and transethosomes have been explored as non-invasive systems for transdermal delivery of drugs. In the present study, different vesicular carriers were prepared by the thin-film hydration method with modification, and various parameters like size, elasticity, and release profiles were evaluated. Ethosomes and transethosomes have shown the smaller size of 362.21 ± 55.76 and 314.34 ± 41.21 nm, with deformity of 19.34% and 25.04%, respectively, compared with liposomes. The FTIR study of the skin before and after the application of vesicular formulation was performed. The ethosomes and transethosomes changed the orthorhombic phase to the liquid crystalline phase to move the vesicular carrier with the drug to cross the stratum corneum (SC) of the skin. The thermotropic behaviour of drug and vesicular carrier ingredients was studied using differential scanning calorimetry (DSC). Fluorescence images of vesicular-skin permeation have revealed that ethosome and transethosome formulation have shown deeper penetration across the SC and epidermis. The in vitro drug release from the ethosomes and transethosomes has shown 93.34 ± 1.23% and 95.45 ± 2.67% of drug release using Franz diffusion cell and porcine skin as a membrane. The nanostructured flexible vesicular carrier containing ethanol alone and a combination of ethanol and edge activator is a perfect carrier for drug penetration to the deeper skin layer and maintaining the sustained release of drug for a prolonged time.

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.

Topical Administration of Drugs Incorporated in Carriers Containing Phospholipid Soft Vesicles for the Treatment of Skin Medical Conditions

This review focuses on the improved topical treatment of various medical skin conditions by the use of drugs delivered from carriers containing phospholipid soft vesicles. Topical drug delivery has many advantages over other ways of administration, having increased patient compliance, avoiding the first-pass effect following oral drug administration or not requesting multiple doses administration. However, the skin barrier prevents the access of the applied drug, affecting its therapeutic activity. Carriers containing phospholipid soft vesicles are a new approach to enhance drug delivery into the skin and to improve the treatment outcome. These vesicles contain molecules that have the property to fluidize the phospholipid bilayers generating the soft vesicle and allowing it to penetrate into the deep skin layers. Ethosomes, glycerosomes and transethosomes are soft vesicles containing ethanol, glycerol or a mixture of ethanol and a surfactant, respectively. We review a large number of publications on the research carried out in vitro, in vivo in animal models and in humans in clinical studies, with compositions containing various active molecules for treatment of skin medical conditions including skin infections, skin inflammation, psoriasis, skin cancer, acne vulgaris, hair loss, psoriasis and skin aging.

Topical Allopurinol-Loaded Nanostructured Lipid Carriers: A Novel Approach for Wound Healing Management

Nanostructured lipid carriers (NLC) have been widely studied as delivery systems for a variety of routes, including the skin. Their composition results in an imperfect lipid matrix, allowing increased drug encapsulation. Allopurinol (AP), a xanthine oxidase inhibitor, is characterized by low water solubility and high melting point, which has hampered its use through the topical route. In this work, AP was incorporated in a NLC formulation to enhance drug-carrier association and skin delivery as a topical approach to treat wounds. AP-NLC system was characterized in terms of size, charge, rheological behavior, and in vitro skin permeation. The in vitro cytotoxicity was evaluated using HaCaT cells. The wound healing efficacy of the AP-NLC formulation on animal skin lesions was evaluated in male Wistar rats. The AP-NLC presented a mean size of 193 ± 15 nm with a PdI of 0.240 ± 0.02, zeta potential values around −49.6 mV, and an encapsulation efficiency of 52.2%. The AP-NLC formulation presented an adequate profile to be used topically, since epidermal and dermal drug retention were achieved. No reduction in HaCaT cells viability was observed at the tested concentrations (AP < 10 μg/mL). The in vivo application of the AP-NLC formulation resulted in the regeneration of skin lesions when compared with non-treated controls.

Lipid Nanoparticulate Drug Delivery Systems: Recent Advances in the Treatment of Skin Disorders

The multifunctional role of the human skin is well known. It acts as a sensory and immune organ that protects the human body from harmful environmental impacts such as chemical, mechanical, and physical threats, reduces UV radiation effects, prevents moisture loss, and helps thermoregulation. In this regard, skin disorders related to skin integrity require adequate treatment. Lipid nanoparticles (LN) are recognized as promising drug delivery systems (DDS) in treating skin disorders. Solid lipid nanoparticles (SLN) together with nanostructured lipid carriers (NLC) exhibit excellent tolerability as these are produced from physiological and biodegradable lipids. Moreover, LN applied to the skin can improve stability, drug targeting, occlusion, penetration enhancement, and increased skin hydration compared with other drug nanocarriers. Furthermore, the features of LN can be enhanced by inclusion in suitable bases such as creams, ointments, gels (i.e., hydrogel, emulgel, bigel), lotions, etc. This review focuses on recent developments in lipid nanoparticle systems and their application to treating skin diseases. We point out and consider the reasons for their creation, pay attention to their advantages and disadvantages, list the main production techniques for obtaining them, and examine the place assigned to them in solving the problems caused by skin disorders.

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.

Recent Advances in Nanomaterials for Dermal and Transdermal Applications

The stratum corneum, the most superficial layer of the skin, protects the body against environmental hazards and presents a highly selective barrier for the passage of drugs and cosmetic products deeper into the skin and across the skin. Nanomaterials can effectively increase the permeation of active molecules across the stratum corneum and enable their penetration into deeper skin layers, often by interacting with the skin and creating the distinct sites with elevated local concentration, acting as reservoirs. The flux of the molecules from these reservoirs can be either limited to the underlying skin layers (for topical drug and cosmeceutical delivery) or extended across all the sublayers of the epidermis to the blood vessels of the dermis (for transdermal delivery). The type of the nanocarrier and the physicochemical nature of the active substance are among the factors that determine the final skin permeation pattern and the stability of the penetrant in the cutaneous environment. The most widely employed types of nanomaterials for dermal and transdermal applications include solid lipid nanoparticles, nanovesicular carriers, microemulsions, nanoemulsions, and polymeric nanoparticles. The recent advances in the area of nanomaterial-assisted dermal and transdermal delivery are highlighted in this review.

Amphotericin B-loaded deformable lipid vesicles for topical treatment of cutaneous leishmaniasis skin lesions

Cutaneous leishmaniasis (CL), the most common clinical form of human leishmaniasis, is a non-fatal chronic and disabling disease characterized by erythema and nodular or ulcerative skin lesions that may cause permanent scars and disfigurement. Topical drug delivery represents a simple and efficacious approach to treat CL skin lesions. The association of drugs with nanocarrier systems enhances their permeation properties and increases the drug amount available in the dermis. Here, a deformable lipid vesicle (DLV) was optimized for the topical administration of Amphotericin B (AmB), with the aim of studying and understanding the advantages of this type of delivery system in the transport of a drug through the skin layers. AmB-DVL were characterized in terms of incorporation parameters, stability, and elasticity, and evaluated in vitro for their permeation properties, cytotoxicity, and anti-leishmanial activity. The AmB-DVL exhibited a translucent fluid gel-like aspect and a yellow color, a mean size of 132 nm (PdI ≤ 0.1), zeta potential values around zero (mV), and an AmB incorporation efficiency of 95%. Permeation and penetration assays suggest that AmB-DLV are suitable for topical administration since AmB was detected in the epidermal and dermal skin layers. AmB-DVL was able to reduce promastigote viability in a dose-dependent manner, as well as the number of intracellular amastigotes in THP-1 macrophages. Selectivity index (SI) value for AmB-DLV was considerably higher than that observed for free AmB. Results suggest that DLV may represent an attractive vehicle for dermal delivery of AmB and a new low-cost and safe therapeutic option in CL treatment.

Physical Enhancement? Nanocarrier? Current Progress in Transdermal Drug Delivery

A transdermal drug delivery system (TDDS) is a method that provides drug adsorption via the skin. TDDS could replace conventional oral administration and blood administration because it is easily accessible. However, it is still difficult to design efficient TDDS due to the high barrier property of skin covered with stratum corneum, which inhibits the permeation of drug molecules. Thus far, TDDS methods by applying physical stimuli such as microneedles and chemical stimuli such as surfactants have been actively developed. However, it has been hard to avoid inflammation at the administration site because these methods partially destroy the skin tissue. On the other hand, TDDS with nanocarriers minimizing damage to the skin tissues has emerged together with the development of nanotechnology in recent years. This review focuses on current trends in TDDS.

An evaluation of tocotrienol ethosomes for transdermal delivery using Strat-M® membrane and excised human skin

Tocotrienol (TRF) ethosomes were developed and evaluated in vitro for potential transdermal delivery against melanoma. The optimised TRF ethosomal size ranged between 64.9 ± 2.2 nm to 79.6 ± 3.9 nm and zeta potential (ZP) between -53.3 mV to -62.0 ± 2.6 mV. Characterisation of the ethosomes by ATR-FTIR indicated the successful formation of TRF-ethosomes. Scanning electron microscopy (SEM) images demonstrated the spherical shape of ethosomes, and the entrapment efficiencies of all the formulations were above 66%. In vitro permeation studies using full-thickness human skin showed that the permeation of gamma-T3 from the TRF ethosomal formulations was significantly higher (p < 0.05) than from the control. The cumulative amount of gamma-T3 permeated from TRF ethosome after 48 hours was 1.03 ± 0.24 µg cm^-2 with a flux of 0.03 ± 0.01 µg cm^-2 h^-1. Furthermore, the flux of gamma-T3 across the Strat-M ^® and the epidermal membrane was significantly higher than that across full-thickness human skin (p < 0.05). In vitro cytotoxicity studies on HaCat cells showed significantly higher cell viability than the pure drug solution (p < 0.05). The enhanced skin permeation and high cell viability associated with this formulation suggest a promising carrier for transdermal delivery.

Deformable Liposomal Hydrogel for Dermal and Transdermal Delivery of Meloxicam

Background and Aim

Meloxicam (MX) is a potent hydrophobic non-steroidal anti-inflammatory drug used to reduce inflammation and pain. However, its oral dosage form can cause many adverse gastrointestinal effects. In the present study, a poloxamer P407 based hydrogel system containing transfersomes or flavosomes has been prepared as a potential therapeutic vehicle for the topical delivery of MX.

Methods

In this study, MX was encapsulated in conventional liposomes, transfersomes, and flavosomes. The obtained liposomal vesicles were characterized in terms of size, drug entrapment efficiency, zeta potential, and stability. These MX-loaded liposomal formulations were further incorporated into a poloxamer P407 gel and evaluated using rheological properties, a stability study and an ex vivo permeation study through human cadaver skin by both HPLC analysis and confocal laser scanning microscopy (CLSM).

Results

The developed deformable liposomes exhibited homogeneous vesicle sizes less than 120 nm with a higher entrapment efficiency as compared to conventional liposomes. The deformable liposomal gel formulations showed improved permeability compared to a conventional liposomal gel and a liposome-free gel. The enhancement effect was also clearly visible by CLSM.

Conclusion

These deformable liposomal hydrogel formulations can be a promising alternative to conventional oral delivery of MX by topical administration. Notably, flavosome-loaded gel formulations displayed the highest permeability through the deeper layers of the skin and shortened lag time, indicating a potential faster on-site pain relief and anti-inflammatory effect.

The Challenge of Nanovesicles for Selective Topical Delivery for Acne Treatment: Enhancing Absorption Whilst Avoiding Toxicity

Acne is a common skin disease that affect over 80% of adolescents. It is characterized by inflammation of the hair bulb and the attached sebaceous gland. To date, many strategies have been used to treat acne as a function of the disease severity. However, common treatments for acne seem to show several side effects, from local irritation to more serious collateral effects. The use of topical vesicular carriers able to deliver active compounds is currently considered as an excellent approach in the treatment of different skin diseases. Many results in the literature have proven that drug delivery systems are useful in overcoming the toxicity induced by common drug therapies, while maintaining their therapeutic efficacy. Starting from these assumptions, the authors reviewed drug delivery systems already realized for the topical treatment of acne, with a focus on their limitations and advantages over conventional treatment strategies. Although their exact mechanism of permeation is not often completely clear, deformable vesicles seem to be the best solution for obtaining a specific delivery of drugs into the deeper skin layers, with consequent increased local action and minimized collateral effects.

Prospective Nanotechnology-Based Strategies for Enhanced Intra- and Transdermal Delivery of Antifungal Drugs

Topical therapy of superficial fungal infections allows the prevention of systemic side effects and provides drug targeting at the site of disease. However, an appropriate drug concentration in these sites should be provided to ensure the efficacy of such local treatment. The enhancement of intra- and transdermal penetration and accumulation of antifungal drugs is an important aspect here. The present overview is focused on novel nano-based formulations served to improve antimycotic penetration through the skin. Furthermore, it summarizes various approaches towards the stimulation of drug penetration through and into the stratum corneum and hair follicles, which are considered to be promising for the future improvement of superficial antifungal therapy as providing the drug localization and prolonged storage property at the targeted area.

Innovative strategies to treat skin wounds with mangiferin: fabrication of transfersomes modified with glycols and mucin

Aim: The moisturizing properties of glycerol, the penetration enhancing capability of propylene glycol and the bioadhesive properties of mucin were combined to improve the carrier capabilities of transfersomes and the efficacy of mangiferin in the treatment of skin lesions. Materials & methods: Mangiferin was incorporated in transfersomes and glycoltransfersomes, which were also modified with mucin. The physico-chemical features were assessed, along with the efficacy against oxidative stress and skin wounds in vitro and in vivo. Results: Glycoltransfersomes promoted the deposition of mangiferin in epidermis and dermis, protected fibroblasts from oxidative stress and stimulated their proliferation. The wound healing and anti-inflammatory efficacy of glycoltransfersomes were confirmed in vivo. Conclusion: Results confirmed the potential of glycoltransfersomes in preventing/treating of skin lesions.

Skin Permeation of Nanoparticles: Mechanisms Involved and Critical Factors Governing Topical Drug Delivery

Transdermal route has been an ever sought-after means of drug administration, regarded as being the most convenient and patient compliant. However, skin poses a great barrier to the entry of the external particles including bacteria, viruses, allergens, and drugs as well (mostly hydrophilic or high molecular weight drugs), consequent to its complex structure and composition. Among the various means of enhancing drug permeation through the skin, e.g. chemical permeation enhancers, electroporation, thermophoresis, etc. drug delivery through nanoparticles has been of great interest. Current literature reports a vast number of nanoparticles that have been implicated for drug delivery through the skin. However, a precise account of critical factors involved in drug delivery and mechanisms concerning the permeation of nanoparticles through the skin is necessary. The purpose of this review is to enumerate the factors crucial in governing the prospect of drug delivery through skin and classify the skin permeation mechanisms of nanoparticles. Among the various mechanisms discussed are the ones governed by principles of kinetics, osmotic gradient, adhesion, hydration, diffusion, occlusion, electrostatic interaction, thermodynamics, etc. Among the most common factors affecting skin permeation of nanoparticles that are discussed include size, shape, surface charge density, composition of nanoparticles, mechanical stress, pH, etc.

Phospholipid Vesicles for Dermal/Transdermal and Nasal Administration of Active Molecules: The Effect of Surfactants and Alcohols on the Fluidity of Their Lipid Bilayers and Penetration Enhancement Properties

This is a comprehensive review on the use of phospholipid nanovesicles for dermal/transdermal and nasal drug administration. Phospholipid-based vesicular carriers have been widely investigated for enhanced drug delivery via dermal/transdermal routes. Classic phospholipid vesicles, liposomes, do not penetrate the deep layers of the skin, but remain confined to the upper stratum corneum. The literature describes several approaches with the aim of altering the properties of these vesicles to improve their penetration properties. Transfersomes and ethosomes are the most investigated penetration-enhancing phospholipid nanovesicles, obtained by the incorporation of surfactant edge activators and high concentrations of ethanol, respectively. These two types of vesicles differ in terms of their structure, characteristics, mechanism of action and mode of application on the skin. Edge activators contribute to the deformability and elasticity of transfersomes, enabling them to penetrate through pores much smaller than their own size. The ethanol high concentration in ethosomes generates a soft vesicle by fluidizing the phospholipid bilayers, allowing the vesicle to penetrate deeper into the skin. Glycerosomes and transethosomes, phospholipid vesicles containing glycerol or a mixture of ethanol and edge activators, respectively, are also covered. This review discusses the effects of edge activators, ethanol and glycerol on the phospholipid vesicle, emphasizing the differences between a soft and an elastic nanovesicle, and presents their different preparation methods. To date, these differences have not been comparatively discussed. The review presents a large number of active molecules incorporated in these carriers and investigated in vitro, in vivo or in clinical human tests.

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.

Ethosomes for Dermal Administration of Natural Active Molecules

Ethosomes are nanovesicular carriers for dermal administration. Phospholipids, ethanol at relatively high concentrations (up to 50%) and water are their main components. Ethosomes are what we call "soft vesicles" with fluid bilayers due to the presence of ethanol. The composition and structure of the vesicles augment their ability to entrap molecules with various physicochemical properties and deliver them to the deep strata of skin. Since their first design, ethosomal systems have been extensively investigated for a wide range of applications. This review focuses on work carried out in vitro, in vivo in animal models and in humans in clinical studies, with ethosomal formulations containing natural active molecules for the treatment of skin disorders. Skin bacterial and fungal infections, skin inflammation, acne vulgaris, arthritis, and skin cancer are examples of disorders managed successfully by ethosomal systems. Furthermore, Ethosomes loaded with a number of naturally occurring compounds for cosmetic applications are also reported. The efficient treatments together with a good safety profile and lack of toxicity or irritation paved the way towards the development of new dermal therapies.

The transdermal performance, pharmacokinetics, and anti-inflammatory pharmacodynamics evaluation of harmine-loaded ethosomes

Harmine (HAR) is a β-carboline alkaloid with anti-inflammatory and antipruritic effect. However, the low bioavailability and side effects of HAR severely limited its clinical application. The main objective of this study was to develop harmine-loaded ethosomes (HLE) drug delivery system for topical application to treat inflammation. HLE were obtained by ethanol injection method and characterized. The morphology of HLE was evaluated by transmission electron microscopy (TEM). HLE exhibited a good biocompatibility with human embryonic skin fibroblasts and rat skin. The in vitro skin penetration studies showed that HLE had the greatest skin deposition than harmine-loaded liposomes (HLL) and harmine solution (HS). In vivo pharmacokinetic study demonstrated that AUC_(0-∞) and C_max of HLE in subcutaneous tissues were much higher than that of in blood. Moreover, for convenience of fixing on skin, HLE were mixed with gel. HLE gel significantly inhibited the overexpression of inflammation cytokines prostaglandin E2, interleuking (IL)-1β, nitric oxide, and tumor necrosis factor-alpha (TNF-α) in the inflammation model of rat paw edema compared with HS gel. In short, HLE was promising formulation for topical delivery in treatment of inflammatory diseases.

Topical Drug Delivery of Anti-infectives Employing Lipid-Based Nanocarriers: Dermatokinetics as an Important Tool

BACKGROUND

The therapeutic approaches for the management of topical infections have always been a difficult approach due to lack of efficacy of conventional topical formulations, high frequency of topical applications and non-patient compliance. The major challenge in the management of topical infections lies in antibiotic resistance which leads to severe complications and hospitalizations resulting in economic burden and high mortality rates.

METHODS

Topical delivery employing lipid-based carriers has been a promising strategy to overcome the challenges of poor skin permeation and retention along with large doses which need to be administered systemically. The use of lipid-based delivery systems is a promising strategy for the effective topical delivery of antibiotics and overcoming drug-resistant strains in the skin. The major systems include transfersomes, niosomes, ethosomes, solid lipid nanoparticles, nanostructured lipid carriers, microemulsion and nanoemulsion as the most promising drug delivery approaches to treat infectious disorders. The main advantages of these systems include lipid bilayer structure which mimics the cell membrane and can fuse with infectious microbes. The numerous advantages associated with nanocarriers like enhanced efficacy, improvement in bioavailability, controlled drug release and ability to target the desired infectious pathogen have made these carriers successful.

CONCLUSION

Despite the number of strides taken in the field of topical drug delivery in infectious diseases, it still requires extensive research efforts to have a better perspective of the factors that influence drug permeation along with the mechanism of action with regard to skin penetration and deposition. The final objective of the therapy is to provide a safe and effective therapeutic approach for the management of infectious diseases affecting topical sites leading to enhanced therapeutic efficacy and patient-compliance.

Mechanism investigation of ethosomes transdermal permeation

Ethosomes are widely used to promote transdermal permeation of both lipophilic and hydrophilic drugs, but the mechanism of interaction between the ethosomes and the skin remains unclear. In this work, it was exploded with several technologies and facilities. Firstly, physical techniques such as attenuated total reflectance fourier-transform infrared and laser confocal Raman were used and the results indicated that the phospholipids configuration of stratum corneum changes from steady state to unstable state with the treatment of ethosomes. Differential scanning calorimetry reflected the thermodynamics change in stratum corneum after treatment with ethosomes. The results revealed that the skin of Bama mini-pigs, which is similar to human skin, treated by ethosomes had a relatively low T_m and enthalpy. Scanning electron microscopy and transmission electron microscopy showed that the microstructure and ultrastructure of stratum corneum was not damaged by ethosomes treatment. Furthermore, confocal laser scanning microscopy revealed that lipid labeled ethosomes could penetrate the skin via stratum corneum mainly through intercellular route, while during the process of penetration, phospholipids were retained in the upper epidermis. Cell experiments confirmed that ethosomes were distributed mainly on the cell membrane. Further study showed that only the drug-loaded ethosomes increased the amount of permeated drug. The current study, for the first time, elucidated the mechanistic behavior of ethosomes in transdermal application from molecular configuration, thermodynamic properties, ultrastructure, fluorescent labeling and cellular study. It is anticipated that the approaches and results described in the present study will benefit for better design of drug-loaded ethosomes.

A mycophenolic acid derivative from the fungus Penicillium sp. SCSIO sof101

Mycophenolic acid (MPA) is a group of metabolite derived from several species of Penicillium, which shows potent bioactivity. In this study, a new derivative of MPA compound named penicacid D (1), was isolated from the marine derived fungus Penicillium sp. SCSIO sof101, along with seven known compounds (2-8). Their structures were elucidated based on the HR-ESI-MS and NMR data. Moreover, the ¹H and ¹³C NMR data of compound 2 and the ¹³C NMR data of compound 3 are reported. Compounds 1, 4 and 6 exhibited weak activities against Escherichia coli (clinical isolation number 100385570) and Acinetobacter baumannii (clinical isolation number 100069).

Paeonol-Loaded Ethosomes as Transdermal Delivery Carriers: Design, Preparation and Evaluation

Paeonol exhibits a wide range of pharmacological activities, such as anti-inflammatory, antidiabetic as well as pain-relieving activities. However, its intrinsic properties, such as low water solubility, poor stability and low oral bioavailability, restrict its clinical application. The current study aimed to optimize paeonol-loaded ethosomal formulation and characterize it in terms of encapsulation efficiency (EE), vesicle size (VS), zeta potential (ZP) and polydispersity index (PDI), in addition to differential scanning calorimetry (DSC), X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FT-IR) studies. Here, paeonol-loaded ethosomes were prepared by the injection method and optimized by the single-factor test and central composite design-response surface methodology. The optimized paeonol-loaded ethosomes had an EE of 84.33 ± 1.34%, VS of 120.2 ± 1.3 nm, negative charge of −16.8 ± 0.36 mV, and PDI of 0.131 ± 0.006. Ethosomes showed a spherical morphology under the transmission electron microscope (TEM). DSC, XRD and FT-IR results indicated that paeonol was successfully incorporated into the ethosomes. In-vitro transdermal absorption and skin retention of paeonol from paeonol-loaded ethosomes were 138.58 ± 9.60 µg/cm² and 52.60 ± 7.90 µg/cm², respectively. With reasonable skin tolerance, ethosomes could be a promising vehicle for transdermal delivery of paeonol.

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.