Lipid vesicles for skin delivery of drugs: reviewing three decades of research

From lab to industrial development of lipid nanocarriers using quality by design approach

Lipid nanocarriers have attracted a great deal of interest in the delivery of therapeutic molecules. Despite their many advantages, compliance with quality standards and reproducibility requirements still constrain their industrial production. The relatively high failure rate in lipid nanocarrier research and development can be attributed to immature bottom-up manufacturing practices, leading to suboptimal control of quality attributes. Recently, the pharmaceutical industry has moved toward quality-driven manufacturing, emphasizing the integration of product and process development through the principles of quality by design. Quality by design in the pharmaceutical industry involves a thorough understanding of the quality profile of the target product and involves an assessment of potential risks during the design and development phases of pharmaceutical dosage forms. By identifying essential quality characteristics, such as the active ingredients, excipients and manufacturing processes used during research and development, it becomes possible to effectively control these aspects throughout the life cycle of the drug. Successful commercialization of lipid nanocarriers can be achieved if large-scale challenges are addressed using the QbD approach. QbD has become an essential tool because of its advantages in improving processes and product quality. The application of the QbD approach to the development of lipid nanocarriers can provide comprehensive and remarkable knowledge enabling the manufacture of high-quality products with a high degree of regulatory flexibility. This article reviews the basic considerations of QbD and its application in the laboratory and large-scale development of lipid nanocarriers. Furthermore, it provides forward-looking guidance for the industrial production of lipid nanocarriers using the QbD approach.

Preparation and evaluation the effects of retinoic acid loaded proliposomal nanofibers on microbial biofilm inhibition

The electrospinning method involves the production of different drug delivery applications using various polymers. The production of proliposomes with electrospinning provides the hybridization of two novel drug delivery systems. Retinoic acid, also known as all-trans retinoic acid (ATRA), is a common and effective drug for acne therapy. This study aimed to prepare ATRA-loaded proliposomal nanofibers and evaluate their effectiveness on biofilm inhibition. Blank and ATRA-loaded proliposomal nanofiber formulations were fabricated in various polyvinylpyrrolidone, phosphatidylcholine and cholesterol ratios. TEM images verified the rapid formation of the liposomes after the hydration of nanofibers. The vesicle size, polydispersity index and zeta potential values of self-assembled liposomes were measured. The vesicle size values were found to be 321.9-363.8nm with PDI values varying between 0.332-0.511 and zeta potential values of (-16.8)-(-20.5)mV. ATRA-loaded proliposomal nanofibers provided higher bioadhesion (0.25mJ/cm2) than the commercial cream (0.07mJ/cm2). The short-term stability results showed that the initial characteristics remained for three months at 4 °C. The proposed ATRA-loaded self-assembled proliposomal system provided antibacterial, fungistatic or fungicidal effects superior to retinoic acid itself and inhibited biofilm formation in lower concentrations. This approach can combine the stability advantage of nanofibers in the dry state with the high effectiveness of liposomes in acne treatment presenting antibacterial and anti-biofilm-forming activity against Candida albicans and Cutibacterium acnes.

An overview of phospholipid enriched-edge activator-based vesicle nanocarriers: New paradigms to treat skin cancer

Skin cancer poses a significant global health concern necessitating innovative treatment approaches. This review explores the potential of vesicle nanoformulation incorporating EA (edge activators) to overcome barriers in skin cancer management. The skin's inherent protective mechanisms, specifically the outermost layer called the stratum corneum and the network of blood arteries, impede the permeation of drugs. Phospholipid-enriched EA based nanoformulation offer a promising solution by enhancing drug penetration through skin barriers. EAs like Span 80, Span 20, Tween 20, and sodium cholate etc., enhance vesicles deformability, influencing drug permeation. This review discusses topical application of drugs treat skin cancer, highlighting challenges connected with the conventional liposome and the significance of using EA-based nanoformulation in overcoming these challenges. Furthermore, it provides insights into various EA characteristics, critical insights, clinical trials, and patents. The review also offers a concise overview of composition, preparation techniques, and the application of EA-based nanoformulation such as transfersomes, transliposomes, transethosomes, and transniosomes for delivering drugs to treat skin cancer. Overall, this review intends to accelerate the development of formulations that incorporate EA, which would further improve topical drug delivery and enhance therapeutic outcomes in skin cancer treatment.

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.

Mechanism, Formulation, and Efficacy Evaluation of Natural Products for Skin Pigmentation Treatment

Skin pigmentation typically arises from the excessive secretion and accumulation of melanin, resulting in a darker complexion compared to normal skin. Currently, the local application of chemical drugs is a first-line strategy for pigmentation disorders, but the safety and efficacy of drugs still cannot meet clinical treatment needs. For long-term and safe medication, researchers have paid attention to natural products with higher biocompatibility. This article begins by examining the pathogenesis and treatment approaches of skin pigmentation diseases and summarizes the research progress and mechanism of natural products with lightening or whitening effects that are clinically common or experimentally proven. Moreover, we outline the novel formulations of natural products in treating pigmentation disorders, including liposomes, nanoparticles, microemulsions, microneedles, and tocosomes. Finally, the pharmacodynamic evaluation methods in the study of pigmentation disorder were first systematically analyzed. In brief, this review aims to collect natural products for skin pigmentation treatment and investigate their formulation design and efficacy evaluation to provide insights for the development of new products for this complex skin disease.

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.

Application of biomacromolecule-based passive penetration enhancement technique in superficial tumor therapy: A review

Transdermal drug delivery (TDD) has shown great promise in superficial tumor therapy due to its noninvasive and avoidance of the first-pass effect. Especially, passive penetration enhancement technique (PPET) provides the technical basis for TDD by temporarily altering the skin surface structure without requiring external energy. Biomacromolecules and their derived nanocarriers offer a wide range of options for PPET development, with outstanding biocompatibility and biodegradability. Furthermore, the abundant functional groups on biomacromolecule surfaces can be modified to yield functional materials capable of targeting specific sites and responding to stimuli. This enables precise drug delivery to the tumor site and controlled drug release, with the potential to replace traditional drug delivery methods and make PPET-related personalized medicine a reality. This review focuses on the mechanism of biomacromolecules and nanocarriers with skin, and the impact of nanocarriers' surface properties of nanocarriers on PPET efficiency. The applications of biomacromolecule-based PPET in superficial tumor therapy are also summarized. In addition, the advantages and limitations are discussed, and their future trends are projected based on the existing work of biomacromolecule-based PPET.

Complex Emulsions as an Innovative Pharmaceutical Dosage form in Addressing the Issues of Multi-Drug Therapy and Polypharmacy Challenges

This review explores the intersection of microfluidic technology and complex emulsion development as a promising solution to the challenges of formulations in multi-drug therapy (MDT) and polypharmacy. The convergence of microfluidic technology and complex emulsion fabrication could herald a transformative era in multi-drug delivery systems, directly confronting the prevalent challenges of polypharmacy. Microfluidics, with its unparalleled precision in droplet formation, empowers the encapsulation of multiple drugs within singular emulsion particles. The ability to engineer emulsions with tailored properties-such as size, composition, and release kinetics-enables the creation of highly efficient drug delivery vehicles. Thus, this innovative approach not only simplifies medication regimens by significantly reducing the number of necessary doses but also minimizes the pill burden and associated treatment termination-issues associated with polypharmacy. It is important to bring forth the opportunities and challenges of this synergy between microfluidic-driven complex emulsions and multi-drug therapy poses. Together, they not only offer a sophisticated method for addressing the intricacies of delivering multiple drugs but also align with broader healthcare objectives of enhancing treatment outcomes, patient safety, and quality of life, underscoring the importance of dosage form innovations in tackling the multifaceted challenges of modern pharmacotherapy.

Liposomes in the cosmetics: present and outlook

Liposomes are small spherical vesicles composed of phospholipid bilayers capable of encapsulating a variety of ingredients, including water- and oil-soluble compound, which are one of the most commonly used piggybacking and delivery techniques for many active ingredients and different compounds in biology, medicine and cosmetics. With the increasing number of active cosmetic ingredients, the concomitant challenge is to effectively protect, transport, and utilize these substances in a judicious manner. Many cosmetic ingredients are ineffective both topically and systemically when applied to the skin, thus changing the method of delivery and interaction with the skin of the active ingredients is a crucial step toward improving their effectiveness. Liposomes can improve the delivery of active ingredients to the skin, enhance their stability, and ultimately, improve the efficacy of cosmetics and and pharmaceuticals. In this review, we summarized the basic properties of liposomes and their recent advances of functionalities in cosmetics and and pharmaceuticals. Also, the current state of the art in the field is discussed and the prospects for future research areas are highlighted. We hope that this review will provide ideas and inspiration on the application and development of cosmetics and pharmaceuticals.

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.

Tocopherol succinate-loaded ethosomal gel synthesized by cold method technique: Deeper biophysical characterizations for translational application on human skin

BACKGROUND

Tocopherols are well-known antioxidant and moisturizing agent. Tocopherol succinate (TS) are widely used in many skin products especially used in anti-aging and skin whitening product formulation.

AIM

We previously reported the successful synthesis and preliminary characterizations of stable TS ethosomal gels (TSEG) (DOI: 10.1111/jocd.14907). Herein, we develop and further characterize TSEG to enhance the stability of the developed formulation with increased permeation through skin.

METHODS

Cold method technique was used to prepare TS ethosomes. The developed ethosomal vesicle size was 250 nm, which allowed TS to penetrate through the stratum corneum layer and act on melanocytes. For stability study was assessed by thermogravimetric analysis (TGA) by placing TSEG and unloaded/control ethosomal gel (CEG) at various temperature conditions, that is, 8°C, 25°C, 40°C, and 40°C ± 75% RH for 3 months. Organoleptic evaluation was done in terms of color, odor, and phase separation. Transmission electron microscopy (TEM), Fourier Transform infrared spectroscopy (FTIR), x-ray diffraction spectroscopy (XRD), zeta potential (ZP) and particle size (PS) was used for TSEG physical characterizations. In vitro dissolution and ex-vivo permeation studies (using Franz diffusion cell) were performed for both TSEG and CEG formulations. Human women (N = 34) were used to evaluate in vivo biophysical parameters including erythema, melanin, moisture content, sebum level, and skin elasticity.

RESULTS

Developed formulation was highly thermostable during the 3 months. Erythema, melanin, and sebum level decreased while marked improvement (p < 0.05) in moisture content and elasticity have been observed for the developed TSEG.

CONCLUSION

The developed TSEG formulation was found to be efficient, safe (no adverse effects observed), stable (at least for 3 months), and easy to use for topical application with improved skin complexation and skin integrity.

Preparation of paeoniflorin-glycyrrhizic acid complex transethosome gel and its preventive and therapeutic effects on melasma

Paeoniflorin (PF) and glycyrrhizic acid (GL) have skin beautifying effects of anti-inflammation, anti-oxidation, inhibition of melanin formation, and reduction of skin pigmentation. To improve the transdermal permeability of PF and GL in transdermal drug delivery system (TDDS) and enhance their anti-melasma efficacy, PF-GL transethosome (PF-GL-TE) was prepared by ethanol injection method, and finally gelled with carbomer-940 to form PF-GL-TE gel. Consequently, the obtained PF-GL-TE is small and uniform, with an average particle size and a PDI value of about 167.9 nm and 0.102. PF-GL-TE gel showed sustained release behavior and high transdermal permeability in vitro release and transdermal tests. Meanwhile, PF-GL-TE gel played significant preventive effects on melasma induced by progesterone injection and ultraviolet radiation B (UVB) irradiation. According to the results of H&E staining and Masson staining of rat skin, PF-GL-TE gel can alleviate the skin inflammation of and reduce the loss of collagen fibers of back skin in the melasma model rats. Compared with the PF-GL mixture gel, PF-GL-TE gel significantly attenuated the oxidative damage of liver and skin by increasing the activity of SOD and reducing the content of MDA. The results of Western blot showed that PF-GL-TE gel might down-regulate melanin-related proteins expressions of MITF/TYR/TRP1 and TRP2 to prevent and treat melasma. These findings indicate that PF-GL-TE gel is an effective TDDS for delivering PF and GL into the skin, providing a promising preparation for effective prevention and treatment of melasma.

Unlocking the potential of cosmetic dermal delivery with ethosomes: A comprehensive review

BACKGROUND

In a world where hair loss, acne, and skin whitening are common concerns, ethosomes emerge as a captivating breakthrough in cosmetic drug delivery.

METHOD

This review provides a comprehensive overview of the ethosomal system and assesses its potential as an effective nanocarrier for delivering active ingredients to the skin. The focus is on exploring their applications in various pathologies, particularly skin disorders such as acne, hair loss, and skin pigmentation.

RESULTS

Ethosomes are a novel type of vesicular nanocarrier composed of high concentrations of ethanol (20-45%) and phospholipids. Their unique structure and composition make them an ideal choice for transporting active ingredients through the skin, offering targeted and effective treatment. The inclusion of ethanol in ethosomes' composition gives them distinctive properties, including flexibility, deformability, and stability, facilitating deep penetration into the skin and enhancing medication deposition. Moreover, ethosomes improved theoverall drug-loading capacity, and specificity of target treatment CONCLUSION: Ethosomes represent a unique and suitable approach for delivering active cosmetic ingredients in the treatment of hair loss, acne, and skin whitening, presenting a versatile alternative to traditional dermal delivery systems. Despite the challenges associated with their complex preparation and sensitivity to temperature and humidity, the remarkable potential benefits of ethosomes cannot be ignored. Further research is crucial to unlock their full potential, understand their limitations, and refine their formulations and administration methods. Ethosomes hold the promise of transforming the way we address these cosmetic concerns, offering an exciting glimpse into the future of advanced skincare solutions.

Designed Fabrication of Phloretin-Loaded Propylene Glycol Binary Ethosomes: Stability, Skin Permeability and Antioxidant Activity

Binary ethosome vesicles have been developed as flexible lipid vesicles for the enhanced physicochemical stability and skin delivery of drugs. This work aimed to prepare phloretin-loaded propylene glycol ethosomes (PHL-PGEs) to improve their stability, skin permeability and antioxidant activity. PHL-PGEs were prepared via the ethanol injection method and optimized using different weight ratios of ethanol to propylene glycol (PG). When the ethanol/PG mass ratio changed from 10:0 to 0:10, the encapsulation efficiency and stability of ethosomes increased. At a PHL concentration of 1mg/mL, the EE% was 89.42 ± 2.42 and the DL% was 4.21 ± 0.04, which exhibited their highest values. The encapsulation of the PHL in the PHL-PGEs was strengthened via XRD analysis and FTIR analysis. The results of the in vitro percutaneous permeability test demonstrated that the combined use of ethanol and PG exhibited a notable enhancement in skin permeability, and the skin retention of PHL-PGEs was 1.06 times that of PHL-ethosomes (PHL-Es) and 2.24 times that of the PHL solution. An in vitro antioxidant activity study indicated that solubility and antioxidant activity was potentiated via the nanoencapsulation of phloretin. Therefore, these results confirm the potential of this nanocarrier to enhance physicochemical stability, skin permeability and antioxidant activity.

Advanced application of nanotechnology in active constituents of Traditional Chinese Medicines

Traditional Chinese Medicines (TCMs) have been used for centuries for the treatment and management of various diseases. However, their effective delivery to targeted sites may be a major challenge due to their poor water solubility, low bioavailability, and potential toxicity. Nanocarriers, such as liposomes, polymeric nanoparticles, inorganic nanoparticles and organic/inorganic nanohybrids based on active constituents from TCMs have been extensively studied as a promising strategy to improve the delivery of active constituents from TCMs to achieve a higher therapeutic effect with fewer side effects compared to conventional formulations. This review summarizes the recent advances in nanocarrier-based delivery systems for various types of active constituents of TCMs, including terpenoids, polyphenols, alkaloids, flavonoids, and quinones, from different natural sources. This review covers the design and preparation of nanocarriers, their characterization, and in vitro/vivo evaluations. Additionally, this review highlights the challenges and opportunities in the field and suggests future directions for research. Nanocarrier-based delivery systems have shown great potential in improving the therapeutic efficacy of TCMs, and this review may serve as a comprehensive resource to researchers in this field.

Enhanced Delivery of 5-Aminolevulinic Acid by Lecithin Invasomes in 3D Melanoma Cancer Model

Photodynamic therapy (PDT) is a noninvasive therapeutic approach for the treatment of skin cancer and diseases. 5-Aminolevulinic acid is a prodrug clinically approved for PDT. Once internalized by cancer cells, it is rapidly metabolized to the photosensitizer protoporphyrin IX, which under the proper light irradiation, stimulates the deleterious reactive oxygen species (ROS) production and leads to cell death. The high hydrophilicity of 5-aminolevulinic acid limits its capability to cross the epidermis. Lipophilic derivatives of 5-aminolevulinic acid only partly improved skin penetration, thus making its incorporation into nanocarriers necessary. Here we have developed and characterized 5-aminolevulinic acid loaded invasomes made of egg lecithin, either 1,2-dilauroyl-sn-glycero-3-phosphocholine or 1,2-dioleoyl-sn-glycero-3-phosphocholine, and the terpene limonene. The obtained invasomes are highly thermostable and display a spherical morphology with an average size of 150 nm and an encapsulation efficiency of 80%; moreover, the ex vivo epidermis diffusion tests established that nanovesicles containing the terpene led to a much higher skin penetration (up to 80% in 3 h) compared to those without limonene and to the free fluorescent tracer (less than 50%). Finally, in vitro studies with 2D and 3D human cell models of melanoma proved the biocompatibility of invasomes, the enhanced intracellular transport of 5-aminolevulinic acid, its ability to generate ROS upon irradiation, and consequently, its antiproliferative effect. A simplified scaffold-based 3D skin model containing melanoma spheroids was also prepared. Considering the results obtained, we conclude that the lecithin invasomes loaded with 5-aminolevulinic acid have a good therapeutic potential and may represent an efficient tool that can be considered a valid alternative in the topical treatment of melanoma and other skin diseases.

Nanotechnology-empowered strategies in treatment of skin cancer

In current scenario skin cancer is a serious condition that has a significant impact on world health. Skin cancer is divided into two categories: melanoma skin cancer (MSC) and non-melanoma skin cancer (NMSC). Because of its significant psychosocial effects and need for significant investment in new technology and therapies, skin cancer is an illness of global health relevance. From the patient's perspective chemotherapy considered to be the most acceptable form of treatment. However, significant negatives of chemotherapy such as severe toxicities and drug resistance pose serious challenges to the treatment. The field of nanomedicine holds significant promise for enhancing the specificity of targeting neoplastic cells through the facilitation of targeted drug delivery to tumour cells. The integration of multiple therapeutic modalities to selectively address cancer-promoting or cell-maintaining pathways constitutes a fundamental aspect of cancer treatment. The use of mono-therapy remains prevalent in the treatment of various types of cancer, it is widely acknowledged in the academic community that this conventional approach is generally considered to be less efficacious compared to the combination treatment strategy. The employment of combination therapy in cancer treatment has become increasingly widespread due to its ability to produce synergistic anticancer effects, mitigate toxicity associated with drugs, and inhibit multi-drug resistance by means of diverse mechanisms. Nanotechnology based combination therapy represents a promising avenue for the development of efficacious therapies for skin cancer within the context of this endeavour. The objective of this article is to provide a description of distinct challenges for efficient delivery of drugs via skin. This article also provides a summary of the various nanotechnology based combinatorial therapy available for skin cancer with their recent advances. This review also focuses on current status of clinical trials of such therapies.

The Application of Nanogels as Efficient Drug Delivery Platforms for Dermal/Transdermal Delivery

The delivery of active molecules via the skin seems to be an efficient technology, given the various disadvantages of oral drug administration. Skin, which is the largest human organ of the body, has the important role of acting as a barrier for pathogens and other molecules including drugs; in fact, it serves as a primary defense system blocking any particle from entering the body. Therefore, to overcome the skin barriers and poor skin permeability, researchers implement novel carriers which can effectively carry out transdermal delivery of the molecules. Another significant issue which medical society tries to solve is the effective dermal delivery of molecules especially for topical wound delivery. The application of nanogels is only one of the available approaches offering promising results for both dermal and transdermal administration routes. Nanogels are polymer-based networks in nanoscale dimensions which have been explored as potent carriers of poorly soluble drugs, genes and vaccines. The nanogels present unique physicochemical properties, i.e., high surface area, biocompatibility, etc., and, importantly, can improve solubility. In this review, authors aimed to summarize the available applications of nanogels as possible vehicles for dermal and transdermal delivery of active pharmaceutical ingredients and discuss their future in the pharmaceutical manufacturing field.

Advances in transdermal siRNAs delivery: A review of current research progress

Small interfering RNA (siRNAs) is a double-stranded RNA molecule which can hybridize with a specific mRNA sequence and block the translation of numerous genes to regulate endogenous genes and to defend the genome from invasive nucleic acids. The use of siRNAs has been studied as a treatment option for various skin conditions. One of the main obstacles in the dermal or transdermal delivery of this compound is low skin permeability, and application is limited by its negative charge, high polarity, susceptibility to degradation by nucleases, and difficulty in penetrating the skin barrier. Effective delivery of therapeutic biomolecules to their target is a challenging issue, which can be solved by innovations in drug delivery systems and lead to improvement of the efficiency of many new biopharmaceuticals. Designing of novel transdermal delivery systems garnered tremendous attention in both cosmeceutical and pharmaceutical research and industries, which offers a number of advantages. Developing safe and efficient siRNAs delivery vectors is essential for effective treatment of skin diseases. In recent years, significant progress has been made in the creation of delivery systems using lipids, polymers, cell-penetrating peptides, nanoparticles and other biologically active agents. In this review we will focus on the recent advancements in transdermal siRNAs delivery vectors, such as liposomes, dendrimers, cell-penetrating peptides, and spherical nucleic acid nanoparticles.

Development and Evaluation of Nanoformulations Containing Timur Oil and Rosemary Oil for Treatment of Topical Fungal Infections

The pervasiveness of fungal infections is an issue for skin health globally, and there are a reported 40 million cases in developed and developing countries. Novel drug delivery systems provide better therapeutic efficacy over conventional drug therapy due to their lower side effects and toxicity. Furthermore, combinations of essential oils can represent alternative therapies for fungal infections that are resistant to synthetic drugs. This study is aimed at developing Timur oil into a nanoemulgel and evaluating its antifungal effects. The development of the formulation involved the preparation of a nanoemulsion by the titration method, followed by its evaluation for various physicochemical properties. The antifungal activity of the nanoemulgel against Candida albicans was evaluated. The zone of inhibition was determined using the disk diffusion method. The results show that the developed nanoemulgel has a particle size of 139 ± 6.11 nm, a PDI of 0.309, and a zeta potential of -19.12 ± 2.73 mV. An in vitro drug release study showed a sustained release of 70 ± 0.289% of the drug over a period of 24 h. The % drug permeation across the skin was found to be 79.11 ± 0.319% over 24 h. However, the amount of drug retained in the skin was 56.45 µg/g. The flux for the nanoemulgel was found to be 94.947 µg/cm²/h, indicating a better permeability profile. The nanoemulgel formulation showed a zone of inhibition of 15 ± 2.45 mm, whereas the 1% ketoconazole cream (marketed preparation) exhibited a zone of inhibition of 13 ± 2.13 mm. The results of this study suggest that developed nanoemulgel containing Timur oil and rosemary oil has the potential to be used for treating topical fungal infections caused by Candida albicans.

Folate receptor targeted NIR cleavable liposomal delivery system augment penetration and therapeutic efficacy in breast cancer

BACKGROUND

Liposomes are predominantly used sorts of nanocarriers for active targeted delivery through surface functionalization using targeting ligand. The folate receptors are overexpressed in various cancers including breast cancer and because of its binding aptitude specifically to folate receptors, folic acid became the attractive ligand.

METHODS

In this research, we have developed a folate and Poly-l-Lysine conjugate and coated this conjugate onto the liposomes. The prepared liposomes were characterized using DLS, FTIR, NMR, SEM, TEM, XRD, AFM, stability and drug release studies. Furthermore, In vitro studies were carried out on FR overexpressed breast cancer cell line.

RESULTS

The FA-LUT-ABC-Lip have diameter of 183 ± 3.17 nm with positive surface charge +33.65 ± 3 mV and the drug release studies confirm the NIR responsive payload cleavage. The coated formulation (in presence of NIR light) effectively reduced the IC₅₀ values and kills breast cancer cells through FR mediated internalization and accelerated drug release. Moreover, LUT Formulation shows anticancer effect due to significant inhibition of cell migration and proliferation by regulating VEGF expression and induced apoptosis through the caspase-3 up-regulation.

CONCLUSION

It is evident from the in vitro studies that the formulation was found to be very effective and can be explored for triggered and targeted delivery of the substances through active targeting.

GENERAL SIGNIFICANCE

Combining receptor mediated drug delivery with triggered release aid in more amounts of drug reaching the target site and achieving enhanced therapeutic activity.

Potential of Lipid-Based Nanocarriers against Two Major Barriers to Drug Delivery-Skin and Blood-Brain Barrier

Over the past few years, pharmaceutical and biomedical areas have made the most astounding accomplishments in the field of medicine, diagnostics and drug delivery. Nanotechnology-based tools have played a major role in this. The implementation of this multifaceted nanotechnology concept encourages the advancement of innovative strategies and materials for improving patient compliance. The plausible usage of nanotechnology in drug delivery prompts an extension of lipid-based nanocarriers with a special reference to barriers such as the skin and blood-brain barrier (BBB) that have been discussed in the given manuscript. The limited permeability of these two intriguing biological barriers restricts the penetration of active moieties through the skin and brain, resulting in futile outcomes in several related ailments. Lipid-based nanocarriers provide a possible solution to this problem by facilitating the penetration of drugs across these obstacles, which leads to improvements in their effectiveness. A special emphasis in this review is placed on the composition, mechanism of penetration and recent applications of these carriers. It also includes recent research and the latest findings in the form of patents and clinical trials in this field. The presented data demonstrate the capability of these carriers as potential drug delivery systems across the skin (referred to as topical, dermal and transdermal delivery) as well as to the brain, which can be exploited further for the development of safe and efficacious products.

Transfersome Encapsulated with the R-carvedilol Enantiomer for Skin Cancer Chemoprevention

The R-carvedilol enantiomer, present in the racemic mixture of the chiral drug carvedilol, does not bind to the β-adrenergic receptors, but exhibits skin cancer preventive activity. For skin delivery, R-carvedilol-loaded transfersomes were prepared using various ratios of drug, lipids, and surfactants, and characterized for particle size, zeta potential, encapsulation efficiency, stability, and morphology. Transfersomes were compared for in vitro drug release and ex vivo skin penetration and retention. Skin irritation was evaluated by viability assay on murine epidermal cells and reconstructed human skin culture. Single-dose and repeated-dose dermal toxicity was determined in SKH-1 hairless mice. Efficacy was evaluated in SKH-1 mice exposed to single or multiple ultraviolet (UV) radiations. Transfersomes released the drug at a slower rate, but significantly increased skin drug permeation and retention compared with the free drug. The transfersome with a drug-lipid-surfactant ratio of 1:3:0.5 (T-RCAR-3) demonstrated the highest skin drug retention and was selected for further studies. T-RCAR-3 at 100 µM did not induce skin irritation in vitro and in vivo. Topical treatment with T-RCAR-3 at 10 µM effectively attenuated acute UV-induced skin inflammation and chronic UV-induced skin carcinogenesis. This study demonstrates feasibility of using R-carvedilol transfersome for preventing UV-induced skin inflammation and cancer.

ELASTIC CATIONIC LIPOSOMES FOR VITAMIN C DELIVERY: DEVELOPMENT, CHARACTERIZATION AND SKIN ABSORPTION STUDY

The influence of hydrophilic surfactants acting on the membrane elasticity of liposomes on the skin absorption of vitamin C is investigated. The purpose of encapsulation inside cationic liposomes is to improve the skin delivery of vitamin C. The properties of elastic liposomes (ELs) are compared to that of conventional liposomes (CLs). ELs are formed by the addition of the "edge activator" Polysorbate 80 to the CLs composed of soybean lecithin, cationic lipid DOTAP (1,2-dioleoyl-3-trimethylammoniopropane chloride), and cholesterol. The liposomes are characterized by dynamic light scattering and electron microscopy. No toxicity is detected in human keratinocyte cells. Evidences of Polysorbate 80 incorporation into liposome bilayers and of the higher flexibility of ELs are given by isothermal titration calorimetry and pore edge tension measurements in giant unilamellar vesicles. The presence of a positive charge in the liposomal membrane increases the encapsulation efficacy by approximately 30% for both CLs and ELs. Skin absorption of vitamin C from CLs, ELs and a control aqueous solution measured in Franz cells shows a high delivery of vitamin C into each skin layer and the acceptor fluid from both liposome types. These results suggest that another mechanism drives skin diffusion, involving interactions between cationic lipids and vitamin C depending on the skin pH.

Development and optimization of transethosomal gel of apigenin for topical delivery: In-vitro, ex-vivo and cell line assessment

The main aim of this study was to optimize the transethosomes of apigenin formulated by the thin film hydration method using surfactant Span 80. Response surface Box-Behnken design with three levels of three factors was used to design and optimize the formulations. The prepared transethosomal formulations were characterized for entrapment efficiency, vesicle size, and flux to obtain the optimized formulation batch. The optimized batch was further incorporated into the gel and characterized for the in-vitro, ex-vivo, and cytotoxic studies. The result showed the optimized transethosomes were smooth, nanosized, unilamellar, and spherical with an entrapment efficiency of 78.75 ± 3.14 %, a vesicle size of 108.75 ± 2.31 nm, and a flux of 4.10 ± 0.63 µg/cm²/h. In-vitro cumulative drug release of transethosomal gel of apigenin (TEL gel) and the conventional gel was 92.25 ± 3.5 % and 53.40 ± 3.10 %, respectively, after 24 h study. Ex-vivo permeation of TEL gel and conventional gel showed 86.20 ± 3.60 % and 51.20 ± 3.20 % permeation of apigenin at 24 h, respectively. A cytotoxic study confirmed that TEL gel significantly reduces cell viability compared to conventional gel. The results suggested that topical application of apigenin transethosomal gel may be a better treatment strategy for skin cancer because of the prolonged sustained release of the drug and the better permeability of apigenin through the skin.

Film Forming Systems for Delivery of Active Molecules into and across the Skin

We have investigated delivery systems that can form a structured matrix film on the skin after their application. In a previous work, we have shown that Weblike film forming systems (also called Pouches Drug Delivery Systems, PDDS) enable enhanced skin delivery of the incorporated molecules. These delivery systems are composed of one or more phospholipids, a short-chain alcohol, a polymer and optionally water. In this work, we continue the investigation and characterization of Weblike carriers focusing on some factors affecting the delivery properties such as components concentration and mode of application on the skin. Upon non-occluded application on the skin, the systems dry rapidly, forming a web-like structured film. Lidocaine, Ibuprofen, FITC and Cannabidiol are molecules with various physico-chemical properties that were incorporated in the carrier. The systems were tested in a number of in vitro and in vivo experiments. Results of the in vitro permeation of Ibuprofen through porcine skin indicated two-fold delivery through the skin of Ibuprofen when applied from our Weblike system in comparison with a nanovesicular carrier, the ethosome. We also have investigated weblike systems containing hemp seed oil (HSO). This addition enhanced the film's ability to deliver lipophilic molecules to the deeper skin layers, leading to an improved pharmacodynamic effect. In analgesic tests carried out in a pain mice model following one hour application of CBD in Weblike system with and without HSO, the number of writhing episodes was decreased from 29 in the untreated animals to 9.5 and 18.5 writhes, respectively. The results of our work open the way towards a further investigation of Weblike film forming systems containing drugs for improved dermal and transdermal treatment of various ailments.

Ethosomes and their monotonous effects on Skin cancer disruption

Skin cancer is one of the most prominent diseases, affecting all continents worldwide, and has shown a significant rise in mortality and prevalence. Conventional therapy, including chemotherapy and surgery, has a few drawbacks. The ethosomal systems would be thoroughly reviewed in this compilation, and they would be classified based on constituents: classical ethosomes, binary ethosomes, and transethosomes. Ethosomes systems are model lipid vesicular carriers with a substantial portion of ethanol. The impacts of ethosomal system components, preparation techniques, and their major roles in selecting the final characteristics of these nanocarriers are comprehensively reviewed in this chapter. The special techniques for ethosomes, including the cold approach, hot approach, injection method, mechanical dispersion method, and conventional method, are explained in this chapter. Various evaluation parameters of ethosomes were also explained. Furthermore, ethosomal gels, patches, and creams can be emphasised as innovative pharmaceutical drug formulations. Some hybrid ethosomal vesicles possessing combinatorial cancer therapy using nanomedicine could overcome the current drug resistance of specific cancer cells. Through the use of repurpose therapy, phytoconstituents may be delivered more effectively. A wide range of in vivo models are employed to assess their effectiveness. Ethosomes have provided numerous potential skin cancer therapeutic approaches in the future.

Development of skin-permeable flexible liposome using ergosterol esters containing unsaturated fatty acids

Ergosterol (Ergo) and cholesterol contribute to performances of liposomes by increasing membrane packing density and physical stability. However, as these sterols can reduce membrane flexibility, they can lower skin permeability of liposomes. We synthesized ergosterol ester (Ergo-Est) containing unsaturated fatty acid different from Ergo in size and physical properties. In this work, we investigated effects of Ergo-Est and Ergo on physical properties of liposomes. We incorporated Ergo, Ergo-oleate (EO^18:1), Ergo-linoleate (EL^18:2), and Ergo-linolenate (ELn^18:3) into the liposomal membrane of egg phosphatidylcholine and soybean lecithin. Ergo-Est did not reduce membrane fluidity as much as Ergo. Nevertheless, Ergo-Est increased membrane packing density and physical stability of liposomes. EL^18:2 and ELn^18:3 almost maintained membrane flexibility and skin permeability of liposomes, while Ergo significantly reduced them. Skin permeation test demonstrated that EL^18:2 and ELn^18:3 liposomes permeated to the dermis, whereas Ergo liposome mostly remained in the stratum corneum. This is the first report to show that EL^18:2 and ELn^18:3 can be efficient sterol compounds for flexible liposome formulation.

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.

Development of a nanotechnological hydrogel containing desonide nanocapsules in association with acai oil: design and in vivo evaluation

Nanotechnological products have been used as strategies to optimize the therapy and minimize the side effects of topical corticoids. The objective of this study was to develop hydrogels by the addition of sclerotium gum to the suspensions of desonide-loaded açai oil-based nanocapsules and to study their biological effect using an animal model of acute skin inflammation. The hydrogels presented a pH compatible with topical application (4.4 to 5.0), nanometric mean diameter (131 to 165 nm), pseudoplastic behavior, and stability under room conditions during 30 days. The in vitro skin permeation/penetration study demonstrated that a higher amount of desonide (p < 0.05) was retained in the epidermis from the nanotechnological-hydrogels (0.33 to 0.36 µg.cm²) in comparison to the commercial gel cream (0.16 µg.cm²). In the dermis, the nanostructured hydrogels promoted a lower DES retention compared to the non-nanostructured formulations (p < 0.05). This result may indicate a smaller amount of drug reaching the bloodstream and, thus, fewer side effects can be expected. Concerning the anti-inflammatory effect, the developed hydrogels reduced both ear edema and inflammatory cell infiltration, showing an effect comparable to the commercially available formulation, which presents twice the drug concentration. The hydrogels developed may be considered a promising approach to treat dermatological disorders.

Multicomponent Copolymer Planar Membranes with Nanoscale Domain Separation

Domain separation is crucial for proper cellular function and numerous biomedical technologies, especially artificial cells. While phase separation in hybrid membranes containing lipids and copolymers is well-known, the membranes' overall stability, limited by the lipid part, is hindering the technological applications. Here, we introduce a fully synthetic planar membrane undergoing phase separation into domains embedded within a continuous phase. The mono- and bilayer membranes are composed of two amphiphilic diblock copolymers (PEO₄₅-b-PEHOx₂₀ and PMOXA₁₀-b-PDMS₂₅) with distinct properties and mixed at various concentrations. The molar ratio of the copolymers in the mixture and the nature of the solid support were the key parameters inducing nanoscale phase separation of the planar membranes. The size of the domains and resulting morphology of the nanopatterned surfaces were tailored by adjusting the molar ratios of the copolymers and transfer conditions. Our approach opens new avenues for the development of biomimetic planar membranes with a nanoscale texture.

Ammonium Glycyrrhizinate and Bergamot Essential Oil Co-Loaded Ultradeformable Nanocarriers: An Effective Natural Nanomedicine for In Vivo Anti-Inflammatory Topical Therapies

Bergamot essential oil (BEO) and Ammonium glycyrrhizinate (AG), naturally derived compounds, have remarkable anti-inflammatory properties, thus making them suitable candidates for the treatment of skin disorders. Despite this, their inadequate physicochemical properties strongly compromise their topical application. Ultradeformable nanocarriers containing both BEO and AG were used to allow their passage through the skin, thus maximizing their therapeutic activity. Physicochemical characterization studies were performed using Zetasizer Nano ZS and Turbiscan Lab^®. The dialysis method was used to investigate the release profile of the active compounds. In vivo studies were performed on human healthy volunteers through the X-Rite spectrophotometer. The nanosystems showed suitable features for topical cutaneous administration in terms of mean size, surface charge, size distribution, and long-term stability/storability. The co-delivery of BEO and AG in the deformable systems improved both the release profile kinetic of ammonium glycyrrhizinate and deformability properties of the resulting nanosystems. The topical cutaneous administration on human volunteers confirmed the efficacy of the nanosystems. In detail, BEO and AG-co-loaded ultradeformable vesicles showed a superior activity compared to that recorded from the ones containing AG as a single agent. These results are promising and strongly encourage a potential topical application of AG/BEO co-loaded nanocarriers for anti-inflammatory therapies.

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.

Characterization and Ex vivo Evaluation of Curcumin Nanoethosomes for Melanoma treatment

This study aimed at developing curcumin nanoethosomes (Cur-Ets) with superior skin permeation intended for melanoma treatment. Although curcumin is active against many types of skin cancers, a suitable topical formulation is still lacking due to its hydrophobicity and poor skin permeation. The formulation was characterized using Scanning Transmission Electron Microscopy (STEM), atomic force microscopy (AFM), ATR-FTIR, DSC, and XRD. In vitro skin permeation was carried out using human skin, and the cytotoxicity of the formulation was evaluated on human melanoma cells (SK-MEL28). The vesicle size and zeta potential of the Cur-Ets were determined as 67 ± 1.6 nm and - 87.3 ± 3.3 mV, respectively. STEM and AFM analysis further support the size and morphology of the formulation. Curcumin's compatibility with formulation additives was confirmed by ATR-FTIR analysis. In addition, DSC and XRD analyses showed successful drug encapsulation in nanoethosomes. The drug encapsulation efficiency was determined as 87 ± 0.9%. The skin permeation of curcumin from Cur-Ets showed a superior flux (0.14 ± 0.03 µg cm^-2 h^-1) compared to the control (p < 0.05). Cytotoxicity of the formulation demonstrated a time-dependent and concentration-dependent antiproliferative activity against melanoma cells. The developed Cur-Ets is suggested as a promising topical formulation for melanoma treatment.

Liposomal Encapsulation Increases the Efficacy of Azithromycin against Chlamydia trachomatis

Chlamydia trachomatis (C. trachomatis) is an obligate intracellular bacterium linked to ocular and urogenital infections with potentially serious sequelae, including blindness and infertility. First-line antibiotics, such as azithromycin (AZT) and doxycycline, are effective, but treatment failures have also been reported. Encapsulation of antibiotics in liposomes is considered an effective approach for improving their local effects, bioavailability, biocompatibility and antimicrobial activity. To test whether liposomes could enhance the antichlamydial action of AZT, we encapsulated AZT in different surface-charged elastic liposomes (neutral, cationic and anionic elastic liposomes) and assessed their antibacterial potential against the C. trachomatis serovar D laboratory strain as well as the clinical isolate C. trachomatis serovar F. A direct quantitative polymerase chain reaction (qPCR) method was used to measure chlamydial genome content 48 h post infection and to determine the recoverable chlamydial growth. All the liposomes efficiently delivered AZT to HeLa 229 cells infected with the laboratory Chlamydia strain, exhibiting the minimal inhibitory concentrations (MIC) and the minimal bactericidal concentrations (MBC) of AZT even 4–8-fold lower than those achieved with the free AZT. The tested AZT-liposomes were also effective against the clinical Chlamydia strain by decreasing MIC values by 2-fold relative to the free AZT. Interestingly, the neutral AZT-liposomes had no effect on the MBC against the clinical strain, while cationic and anionic AZT-liposomes decreased the MBC 2-fold, hence proving the potential of the surface-charged elastic liposomes to improve the effectiveness of AZT against C. trachomatis.

Mapping hair follicle-targeted delivery by particle systems: What has science accomplished so far?

The importance of the hair follicle in the process of cutaneous drug penetration has been established since this skin appendage was recognized as an entry point for topically applied substances. A comprehensive review on the hair follicle as a target per se is here provided, exploring the current knowledge on both targeted regions and delivery systems that take advantage of this permeation route. The follicular penetration is a complex process, whose effectiveness and efficiency strongly depends on a diversity of different factors including follicular density and size, activity status of hair follicles and physicochemical properties of the topically applied substances. Nanocarriers represent a heterogeneous assembly of molecules organized into particles and they have revolutionized drug delivery in several areas of medicine, pharmacology and cosmetics. As they possess an inherent ability to use the follicular route, they are reviewed here having in perspective the hair follicle zones that they are able to reach as reported. In this way, a follicular road map for the different delivery systems was compiled to assist as a guiding tool for those that have interest in the development and/or application of such delivery systems for hair and skin treatment or care.

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.

Transdermal Drug Delivery Systems and Their Use in Obesity Treatment

Transdermal drug delivery (TDD) has recently emerged as an effective alternative to oral and injection administration because of its less invasiveness, low rejection rate, and excellent ease of administration. TDD has made an important contribution to medical practice such as diabetes, hemorrhoids, arthritis, migraine, and schizophrenia treatment, but has yet to fully achieve its potential in the treatment of obesity. Obesity has reached epidemic proportions globally and posed a significant threat to human health. Various approaches, including oral and injection administration have widely been used in clinical setting for obesity treatment. However, these traditional options remain ineffective and inconvenient, and carry risks of adverse effects. Therefore, alternative and advanced drug delivery strategies with higher efficacy and less toxicity such as TDD are urgently required for obesity treatment. This review summarizes current TDD technology, and the main anti-obesity drug delivery system. This review also provides insights into various anti-obesity drugs under study with a focus on the recent developments of TDD system for enhanced anti-obesity drug delivery. Although most of presented studies stay in animal stage, the application of TDD in anti-obesity drugs would have a significant impact on bringing safe and effective therapies to obese patients in the future.

Development and characterization of catechin-in-cyclodextrin-in-phospholipid liposome to eradicate MRSA-mediated surgical site infection: Investigation of their anti-infective efficacy through in vitro and in vivo studies

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the prime pathogens responsible for surgical site infection (SSI). Treatment of SSI remains challenging because of resistant nature of MRSA, which is a major threat in recent years. Our previous work revealed the antibacterial potential of catechin isolated from cashewnut shell against MRSA. However, the application of catechin to treat MRSA-mediated SSI is hampered because of its poor solubility and low trans-dermal delivery. Hence, the present study focused on developing catechin-in-cyclodextrin-in-phospholipid liposome (CCPL) and evaluating its physicochemical characteristics and anti-infective efficacy through in vitro and in vivo models. Encapsulation of catechin with β-cyclodextrin and soybean lecithin was confirmed through UV-Vis spectroscopy, FTIR, and XRD techniques, while TEM imaging revealed the size of CCPL (206 nm). The CCPL displayed a higher level of water solubility (25.13%) and in vitro permeability (42.14%) compared to pure catechin. A higher level of encapsulation efficiency (98.9%) and antibacterial activity (19.8 mm of ZOI and 31.25 μg/mL of MIC) were noted in CCPL compared to the catechin/cyclodextrin complex. CCPL recorded significant and dose-dependent healing of the incision, significant reduction of bacterial count, improved epithelization, and effective prevention of inflammation in skin samples of SSI-induced Balb/c mice. Data of the present work suggest that the CCPL could be considered as a novel and potential candidate to mitigate MRSA-mediated SSI after clinical trials.

Brucine-Loaded Ethosomal Gel: Design, Optimization, and Anti-inflammatory Activity

Brucine, one of the natural medications obtained from Nux vomica seeds, is used as an anti-inflammatory drug. Several investigations were performed to overcome its drawbacks, which will affect significantly its pharmaceutical formulation. The goal of the current investigation was to design, optimize, and evaluate the anti-inflammatory performance of BRU ethosomal gel. Brucineethosomal formulations were prepared using thin film hydration method and optimized by central composite design approach using three independent variables (lecithin concentration, cholesterol concentration, and ethanol percentage) and three response variables (vesicular size, encapsulation efficiency, and skin permeation). The optimized formulation was examined for its stability and then incorporated into HPMC gel to get BRU ethosomal gel. The obtained BRU-loaded ethosomal gel was evaluated for its physical properties, in vitro release, and ex vivo permeation and skin irritation. Finally, carrageenan-induced rat hind paw edema test was adopted for the anti-inflammatory activity. The developed BRU ethosomal gel exhibited good physical characteristics comparable with the conventional developed BRU gel. In vitro release of BRU from ethosomal gel was effectively extended for 6 h. Permeation of BRU from ethosomes was significantly higher than all formulations (p < 0.05), since it recorded steady state transdermal flux value 0.548 ± 0.03 μg/cm² h with enhancement ratio 2.73 ± 0.23. Eventually, BRU ethosomal gel exhibited potent anti-inflammatory activity as manifested by a significant decrease in rat hind paw inflammation following 24 h. In conclusion, the study emphasized the prospective of ethosomal gel as a fortunate carrier for intensifying the anti-inflammatory effect of Brucine.

Insightful exploring of advanced nanocarriers for the topical/transdermal treatment of skin diseases

Dermatological products constitute a big segment of the pharmaceutical market. From conventional products to more advanced ones, a wide variety of dosage forms have been developed till current date. A representative of the advanced delivery means is carrier-based systems, which can load large number of drugs for treatment of dermatological diseases, or simply for cosmeceutical purposes. To make them more favorable for topical delivery, further incorporation of these carriers in a topical vehicle, such as gels or creams is made. Therefore in this review article, an overview is compiled of the most commonly encountered novel carrier based topical delivery systems; namely lipid based (nanoemulsions, microemulsions, solid lipid nanoparticles [SLNs] and nanostructured lipid carriers [NLCs]), and vesicular carriers (non-deformable, such as liposomes, niosomes, emulsomes and cerosomes, and deformable, such as transfersomes, ethosomes, transethosomes, and penetration enhancer vesicles), with special emphasis on those loaded in a secondary gel vehicle. A special focus was made on the commonly encountered dermatological diseases, such as bacterial and fungal infections, psoriasis, dermatitis, eczema, vitiligo, oxidative damage, aging, alopecia, and skin cancer.

Transfersomes as alternative topical nanodosage forms for the treatment of skin disorders

Topical drug delivery is a promising approach to treat different skin disorders. However, it remains a challenge mainly due to the nature and rigidity of the nanosystems, which limit deep skin penetration, and the unsuccessful demonstration of clinical benefits; greater penetration by itself, does not ensure pharmacological success. In this context, transfersomes have appeared as promising nanosystems; deformability, their unique characteristic, allows them to pass through the epidermal microenvironment, improving the skin drug delivery. This review focuses on the comparison of transfersomes with other nanosystems (e.g., liposomes), discusses recent therapeutic applications for the topical treatment of different skin disorders and highlights the need for further studies to demonstrate significant clinical benefits of transfersomes compared with conventional therapies.

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.

Advanced nanomedicine approaches applied for treatment of skin carcinoma

Skin-cancer is the commonest malignancy affecting huge proportion of the population, reaching heights in terms of morbidity. The treatment strategies are presently focusing on surgery, radiation and chemotherapy, which eventually cause destruction to unaffected cells. To overcome this limitation, wide range of nanoscaled materials have been recognized as potential carriers for delivering selective response to cancerous cells and neoplasms. Nanotechnological approach has been tremendously exploited in several areas, owing to their functional nanometric dimensions. The alarming incidence of skin cancer engenders burdensome effects worldwide, which is further awakening innovational medicinal approaches, accompanying target specific drug delivery tools for coveted benefits to provide reduced toxicity and tackle proliferative episodes of skin cancer. The developed nanosystems for anti-cancer agents include liposomes, ethosomes, nanofibers, solid lipid nanoparticles and metallic nanoparticles, which exhibit pronounced outcomes for skin carcinoma. In this review, skin cancer with its sub-types is explained in nutshell, followed by compendium of specific nanotechnological tools presented, in addition to therapeutic applications of drug-loaded nano systems for skin cancer.