Interactions of surfactants (edge activators) and skin penetration enhancers with liposomes

Functionalized liposomes: an enticing nanocarrier for management of glioma

Glioma is one of the most severe central nervous systems (CNS)-specific tumors, with rapidly growing malignant glial cells accounting for roughly half of all brain tumors and having a poor survival rate ranging from 12 to 15 months. Despite being the most often used technique for glioma therapy, conventional chemotherapy suffers from low permeability of the blood-brain barrier (BBB) and blood-brain tumor barrier (BBTB) to anticancer drugs. When it comes to nanocarriers, liposomes are thought of as one of the most promising nanocarrier systems for glioma treatment. However, owing to BBB tight junctions, non-targeted liposomes, which passively accumulate in most cancer cells primarily via the increased permeability and retention effect (EPR), would not be suitable for glioma treatment. The surface modification of liposomes with various active targeting ligands has shown encouraging outcomes in the recent times by allowing various chemotherapy drugs to pass across the BBB and BBTB and enter glioma cells. This review article introduces by briefly outlining the landscape of glioma, its classification, and some of the pathogenic causes. Further, it discusses major barriers for delivering drugs to glioma such as the BBB, BBTB, and tumor microenvironment. It further discusses modified liposomes such as long-acting circulating liposomes, actively targeted liposomes, stimuli responsive liposomes. Finally, it highlighted the limitations of liposomes in the treatment of glioma and the various actively targeted liposomes undergoing clinical trials for the treatment of glioma.

The Evolution of Emerging Nanovesicle Technologies for Enhanced Delivery of Molecules into and across the Skin

This review focuses on nanovesicular carriers for enhanced delivery of molecules into and across the skin, from their design to recent emerging technologies. During the last four decades, several approaches have been used aiming to design new nanovesicles, some of them by altering the properties of the classic phospholipid vesicle, the liposome. Phospholipid nanovesicular systems, including the phospholipid soft vesicles as well as the non-phospholipid vesicular carries, are reviewed. The altered nanovesicles have served in the manufacture of various cosmetic products and have been investigated and used for the treatment of a wide variety of skin conditions. The evolution and recent advances of these nanovesicular technologies are highlighted in this review.

Limosomes versus hyalurolimosomes loaded with piperine for management of skin cancer

Skin cancer is considered the fifth most commonly occurring cancer worldwide hampering both health and economy. Piperine had proven efficacy in fighting skin cancer cells. Unfortunately, this natural agent had limited ability to penetrate the skin. The aim of the current study was to formulate piperine-loaded limosomes and hyalurolimosomes incorporating limonene as an edge activator and hyaluronic acid as bioactive gelling agent for managing skin cancer. Titration method followed by homogenization was adopted to prepare the nanoliposomal formulations. Characterization involved size, & zeta potential measurements, examination using transmission electron microscope (TEM) and stability study. Biological evaluation of the antitumor activity of piperine nanoliposomal formulations against Ehrlich's (EAC) solid tumor was also performed. Drug loaded limosomes and hyalurolimosomes had particle size; 346.55 ± 8.55 & 372.70 ± 10.83 nm, respectively. Zeta potential was high enough to ensure their stability. TEM micrographs detected the surrounding layer of Hyaluronic acid formed around the spherical limosomal nano-carrier ensuring the formation of Hyalurolimosomes. All stored formulations showed non-significant differences compared with freshly prepared ones at p < 0.05. In addition, A DAD-HPLC method was developed and validated for Piperine analysis in the skin. Upon application of this method, it was found that hyalurolimosomes deliver double the concentration delivered by limosomes. The piperine hyalurolimosome group showed a significant reduction in tumor size with a smaller AUC compared to piperine gel, which was confirmed by in vivo studies. Consequently, hyalurolimosomes loaded with piperine is considered a promising nanocarrier system and a step forward better management of skin cancer introducing new hope in beating this deadly disease.

Resolving acne with optimized adapalene microspongeal gel, in vivo and clinical evaluations

In our pursuit of enhancing acne treatment while minimizing side effects, we developed tailored Adapalene microsponges (MS) optimized using a Box-Behnken design 33. The independent variables, Eudragit RS100 percentage in the polymer mixture, organic phase volume, and drug to polymer percentage, were explored. The optimized formulation exhibited remarkable characteristics, with a 98.3% ± 1.6 production yield, 97.3% ± 1.64 entrapment efficiency, and a particle size of 31.8 ± 1.1 µm. Notably, it achieved a 24 h cumulative drug release of 75.1% ± 1.4. To delve deeper into its efficacy, we evaluated the optimized microspongeal-gel in vitro, in vivo, and clinically. It demonstrated impressive retention in the pilosebaceous unit, a target for acne treatment. Comparative studies between our optimized Adapalene microspongeal gel and marketed Adapalene revealed superior performance. In vivo studies on Propionibacterium acnes-infected mice ears showed a remarkable 97% reduction in ear thickness, accompanied by a significant decrease in inflammatory signs and NF-κB levels, as confirmed by histopathological and histochemical examination. Moreover, in preliminary clinical evaluation, it demonstrated outstanding effectiveness in reducing comedonal lesions while causing fewer irritations. This not only indicates its potential for clinical application but also underscores its ability to enhance patient satisfaction, paving the way for future commercialization.

Deformable Vesicles with Edge Activators for the Transdermal Delivery of Non-Psychoactive Cannabinoids

BACKGROUND

Transdermal delivery of highly lipophilic molecules is challenging due to the strong barrier function of the skin. Vesicles with penetration enhancers are safe and efficient systems that could improve the transdermal delivery of non-psychoactive cannabinoids such as cannabidiol and desoxy-cannabidiol. In the last decades, research interest in desoxy-cannabidiol as a potent drug with anti-nociceptive properties has risen. Still, its scarce market availability poses a limit for both research and clinical applications. Therefore, it is necessary to improve the synthesis to produce sufficient amounts of desoxy-cannabidiol. Moreover, also the formulation aspects for this drug are challenging and require to be addressed to meet an efficient delivery to the patients.

OBJECTIVE

This work aimed to develop innovative phospholipid-based vesicles with propylene glycol (PG), oleic acid (OA), or limonene as edge activators, for the transdermal delivery of highly lipophilic drugs such as non-psychoactive cannabinoids. In particular, desoxy-cannabidiol was selected thanks to its anti-nociceptive activity, and its synthesis was improved enhancing the stereoselectivity of its synthon's production.

METHODS

Desoxy-cannabidiol was synthesized by Lewis acid-mediated condensation of p-mentha-2,8-dien- 1-ol and m-pentylphenol, improving the stereoselectivity of the first synthon's production. Transethosomes containing 20-50% w/w PG, 0.4-0.8% w/w OA, or 0.1-1% w/w limonene were optimized and loaded with cannabidiol or desoxy-cannabidiol (0.07-0.8% w/w, 0.6-7.0 mg/mL). Ex-vivo studies were performed to assess both the skin permeation and accumulation of the cannabinoids, as well as the penetration depth of fluorescein- loaded systems used as models.

RESULTS

An enantioselective bromination was added to the pathway, thus raising the production yield of pmentha- 2,8-dien-1-ol to 81% against 35%, and the overall yield of desoxy-cannabidiol synthesis from 12% to 48%. Optimized transethosomes containing 0.6 mg/mL cannabinoids were prepared with 1:10 PG:lipid weight ratio, 0.54 OA:lipid molar ratio, and 0.3 limonene:lipid molar ratio, showing good nanometric size (208 ± 20.8 nm - 321 ± 26.3 nm) and entrapment efficiency (> 80%). Ex-vivo tests showed both improved skin permeation rates of cannabinoids (up to 21.32 ± 4.27 μg/cm2 cannabidiol), and skin penetration (depth of fluorescein up to 240 μm, with PG).

CONCLUSION

Desoxy-cannabidiol was successfully produced at high yields, and formulated into transethosomes optimized for transdermal delivery. Loaded vesicles showed improved skin penetration of desoxy-cannabidiol, cannabidiol and a lipophilic probe. These results suggest the potential of these carriers for the transdermal delivery of highly lipophilic drugs.

Nanotransethosomes for enhanced transdermal delivery of mangiferin against rheumatoid arthritis: formulation, characterization, invivo pharmacokinetic and pharmacodynamic evaluation

The present research study limns the preparation of MNF loaded transethosomes (MNF-TE) to improve MNF solubility, bioavailability and permeation through skin layers for transdermal delivery. MNF-TE was formulated using thin-film hydration method and optimization was done using Box-Behnken design (BBD). MNF-TEopt was characterized for Polydispersity index (PDI), vesicle size, entrapment efficiency, zeta potential and in vitro MNF release. For further evaluation, Pharmacokinetic study, Transmission electron microscopy (TEM), Skin permeation study and Confocal scanning laser microscopy (CLSM) were performed withal. The MNF-TEopt presented spherical and sealed shape vesicles with small vesicle size of 148.6 nm, entrapment efficiency of 74.23%, PDI of 0.1139 and in vitro release of 65.32%. The CLSM study unveiled that the developed formulation has greater permeation of MNF across the skin layers in comparison with the MNF suspension gel. The pharmacokinetic study demonstrated C_max and AUC_0-24 h of 6.94 ± 0.51 μg/ml and 43.92 ± 7.90 μg.h/ml via transdermal route in comparison to C_max and AUC_0-24 h of 3.74 ± 1.91 μg/ml and 22.96 ± 9.76 μg.h/ml presented by MNF-TE oral administration. The in vivo study revealed that the MNF-TE gel has good anti-arthritic potential in comparison with the standard diclofenac gel which was evinced by radiographic analysis and histopathological studies. Further, skin irritation study on Wistar albino rats confirm that the developed MNF-TE formulation is safer for skin application. The current investigation corroborated that the prepared TE vesicle formulation is a treasured carrier for the MNF transdermal delivery for the management of rheumatoid arthritis.

Transethosome: An ultra-deformable ethanolic vesicle for enhanced transdermal drug delivery

Drug delivery through the skin improves solubility, bioavailability, and unwanted systemic side effects of the drug. The selection of a suitable carrier is a challenging process. The conventional lipid vesicles have some limitations. They deliver the drug in the stratum corneum and have poor colloidal stability. Here comes the need for ultra-deformable lipid vesicles to provide the drug beyond the stratum corneum. Transethosomes are novel ultra-deformable vesicles that can deliver drugs into deeper tissues. The composition of transethosomes includes phospholipid, ethanol and surfactants. Each ingredient has a pivotal role in the properties of the carrier. This review covers the design, preparation method, characterisation, and characteristics of the novel vesicle. Also, we cover the impact of surfactants on vesicular properties and the skin permeation behaviour of novel vesicles.

Intranasal Nanotransferosomal Gel for Quercetin Brain Targeting: I. Optimization, Characterization, Brain Localization, and Cytotoxic Studies

Numerous neurological disorders have a pathophysiology that involves an increase in free radical production in the brain. Quercetin (QER) is a nutraceutical compound that shields the brain against oxidative stress-induced neurodegeneration. Nonetheless, its low oral bioavailability diminishes brain delivery. Therefore, the current study aimed to formulate QER-loaded transferosomal nanovesicles (QER-TFS) in situ gel for QER brain delivery via the intranasal route. This study explored the impacts of lipid amount, edge activator (EA) amount, and EA type on vesicle diameter, entrapment, and cumulative amount permeated through nasal mucosa (24 h). The optimum formulation was then integrated into a thermosensitive gel after its physical and morphological characteristics were assessed. Assessments of the optimized QER-TFS showed nanometric vesicles (171.4 ± 3.4 nm) with spherical shapes and adequate entrapment efficiency (78.2 ± 2.8%). The results of short-term stability and high zeta potential value (-32.6 ± 1.4 mV) of QER-TFS confirmed their high stability. Compared with the QER solution, the optimized QER-TFS in situ gel formulation exhibited sustained release behavior and augmented nasal mucosa permeability. CT scanning of rat brains demonstrated the buildup of gold nanoparticles (GNPs) in the brains of all treatment groups, with a greater level of GNPs noted in the rats given the transferosomal gel. Additionally, in vitro studies on PCS-200-014 cells revealed minimal cytotoxicity of QER-TFS in situ gel. Based on these results, the developed transferosomal nanovesicles may be a suitable nanocarrier for QER brain targeting through the intranasal route.

pH-Responsive Nano-transferosomes of Purpurin-18 Sodium Salt and Doxorubicin for Enhanced Anticancer Efficiency by Photodynamic and Chemo Combination Therapy

Cancer is a devastating disease and a major human health concern. Various combination treatments have been developed to combat cancer. To obtain superior cancer therapy, the objective of this study was to synthesize purpurin-18 sodium salt (P18Na) and design P18Na- and doxorubicin hydrochloride (DOX)-loaded nano-transferosomes as a combination of photodynamic therapy (PDT) and chemotherapy for cancer. The characteristics of P18Na- and DOX-loaded nano-transferosomes were assessed, and the pharmacological efficacy of P18Na and DOX was determined using the HeLa and A549 cell lines. The nanodrug delivery system characteristics of the product were found to range from 98.38 to 217.50 nm and -23.63 to -41.10 mV, respectively. Further, the release of P18Na and DOX from nano-transferosomes exhibited a sustained pH-responsive behavior and burst in physiological and acidic environments, respectively. Accordingly, the nano-transferosomes effectively delivered P18Na and DOX into cancer cells, with less leakage in the body, and exhibited pH-responsive release in cancer cells. A photo-cytotoxicity study to HeLa and A549 cell lines revealed a size-dependent anti-cancer effect. These results suggest that the combined nano-transferosomes of P18Na and DOX are effective in the combination of PDT and chemotherapy for cancer.

Structural Characterization and Optimization of a Miconazole Oral Gel

The development of semisolid formulations, gels in particular, has raised the attention of scientists more and more over the last decades. Because of their biocompatibility, hydrophilic nature, and capacity of absorbing large quantities of water, hydrogels are still one of the most promising pharmaceutical formulations in the pharmaceutical industry. The purpose of this study is to develop an optimal formulation capable of incorporating a water-poorly soluble active ingredient such as miconazole used in the treatment of fungal infections with Candida albicans and Candida parapsilosis. A D-optimal design was applied to study the relationship between the formulation parameter and the gel characteristics. The independent parameters used in this study were the Carbopol 940 concentration (the polymer used to obtain the gel matrix), the sodium hydroxide amount, and the presence/absence of miconazole. Ten different dependent parameters (Y1-Y10) were evaluated (penetrometry, spreadability, viscosity, and tangential tension at 1 and 11 levels of speed whilst destructuring and during the reorganization of the gel matrix). The consistency of the gels ranged from 23.2 mm (GO2) to 29.6 mm (GM5). The least spreadable gel was GO7 (1384 mm²), whilst the gel that presented the best spreadability was GO1 (3525 mm²). The viscosity and the tangential stress at the selected levels (1 and 11) varied due to the different compositions of the proposed gels. The gels were also tested for drug content and antifungal activity. All determinations had satisfying results; the drug content was within limits accepted by Ph. Eur. 10 and all formulations containing miconazole exhibited antifungal activity. An optimal formulation with miconazole was attained, consisting of 0.84% Carbopol 940 and 0.32% sodium hydroxide.

Menthol augmented niosomes for enhanced intestinal absorption of lopinavir

Lopinavir is effective in treatment of HIV infection but experiences low oral bioavailability due to poor solubility, pre-systemic metabolism, and P-gp intestinal efflux. Co-processing with menthol enhanced its dissolution and intestinal permeability. Niosomes comprising Span 60, cholesterol and poloxamer 407 were formulated in absence and presence of menthol. These were evaluated for size, morphology, entrapment efficiency (EE%), lopinavir release and intestinal absorption. The later employed in situ rabbit intestinal absorption model. Niosomes were spherical with vesicle size of 140.2 ± 23 and 148.2 ± 27nm for standard and menthol containing niosomes, respectively. The EE% values were 94.4% and 96.3% for both formulations, respectively. Niosomes underwent slow release during the time course of absorption with menthol hastening lopinavir release, but the release did not exceed 9%. Niosmoal encapsulation enhanced lopinavir intestinal absorption compared with drug solution. This was reflected from the fraction absorbed from duodenum which was 24.15%, 73.09% and 83.23% for solution, standard niosomes and menthol containing vesicles, respectively. These values were 34.32%, 80.8% and 86.56% for the same formulations in case of jejuno-ileum. Lopinavir absorption from niosomes didn't depend on release supporting intact vesicle absorption. The study introduced menthol containing niosomes as carriers for enhanced lopinavir intestinal absorption.

Lipid vesicular gels for topical administration of antioxidants

The application of a formulation on the skin represents an effective way to deliver bio-active molecules for therapeutical purposes. Moreover, the outermost skin layer, the stratum corneum, can be overcome by employing chemical permeation enhancers and edge activators as components. Several lipids can be considered as permeation enhancers, such as the ubiquitous monoolein, one of the most used building blocks for the preparation of lipid liquid crystalline nanoparticles which are applied as drug carriers for nanomedicine applications. Recent papers highlighted how bile salts can affect the phase behavior of monoolein to obtain drug carriers suitable for topical administration, given their role as edge activators into the formulation. Herein, the encapsulation of natural antioxidants (caffeic acid and ferulic acid) into lipid vesicular gels (LVGs) made by monoolein and sodium taurocholate (TC) in water was studied to produce formulations suitable for topical application. TC induces a bicontinuous cubic to multilamellar phase transition for monoolein in water at the given concentrations, and by increasing its content into the formulations, unilamellar LVGs are formed. The encapsulation of the two antioxidants did not affect significantly the structure of the gels. The oscillating rheological studies showed that ferulic acid has a structuring effect on the lipid matrix, in comparison with the empty dispersion and the one containing caffeic acid. These gels were then tested in vitro on new-born pig skin to evaluate their efficacy as drug carriers for topical administration, showing that caffeic acid is mostly retained in the gel whereas ferulic acid is released at a higher degree. The data herein reported provide some further information on the effect of bile salts on the lipid self-assembly to evaluate useful compositions for topical administration of natural antioxidants.

Experimental Design and Optimization of Nano-Transfersomal Gel to Enhance the Hypoglycemic Activity of Silymarin

Current advancements in the research investigations focused at using natural products to generate novel dosage forms with a potential therapeutic impact. Silymarin is a natural product obtained from the herb Silybum marianum that has been shown to have remarkable hypoglycemic activity. Owing to the low enteral absorption, instability in stomach secretion, and poor solubility of Silymarin, it was better to be produced as a topical dosage form. A three-factor, three-level Box Behnken (3³ BB) design was constructed to develop 15 formulations using three independent variables (phospholipid concentration, surfactant concentration, and sonication time) and two dependent variables (encapsulation efficiency and in vitro drug release). The optimized formula was added to HPMC gel and the resulting transfersomal gel was investigated for its characteristics, in vitro, ex vivo and hypoglycemic behaviors. The pH of the Silymarin-loaded transfersomal gel was 7.05, the spreadability was 55.35 mm, and the viscosity was 6.27 Pa. Furthermore, Silymarin loaded transfersomal gel had the greatest transdermal flux (92.41 µg/cm²·h), which was much greater than all other formulations. In vivo observations revealed that Silymarin loaded transfersomal gel significantly reduced blood glucose levels, compared to either Silymarin gel or oral Silymarin suspension. The findings show that the developed transfersomal gel could be an effective carrier for Silymarin transdermal delivery.

Drug delivery to the intestinal lymph by oral formulations

Oral drug delivery systems (DDS) targeting lymphocytes in intestinal lymphatic vessels, ducts, and nodes are useful for treating diverse diseases. The intestinal lymph harbors numerous lymphocyte subsets, and DDS containing lipids such as triglycerides and fatty acids can deliver drugs to the lymph through the chylomicron pathway. DDS are efficient, thus allowing the administration of reduced drug doses, which mitigate systemic adverse effects. Here we review orally administered lipid formulations comprising oil solutions, suspensions, micro/nanoemulsions, self-micro/nano emulsifying DDS, liposomes, micelles, solid lipid nanoparticles, and nanostructured lipid carriers for targeting drugs to the lymph. We first describe the structures of lymphatic vessels and lymph nodes and the oral absorption of lipids and drugs into the intestinal lymph. We next summarize the effects of the properties and amounts of lipids and drugs delivered into the lymph and lymphocytes, as well as their effects on drug delivery ratios of lymph to blood. Finally, we describe lymphatic DDS containing saquinavir, tacrolimus, and methotrexate, and their potency that reduce drug concentrations in blood, which are associated with systemic adverse effects.

Design and Characterisation of pH-Responsive Photosensitiser-Loaded Nano-Transfersomes for Enhanced Photodynamic Therapy

Photodynamic therapy (PDT) is a non-invasive and tumour-specific therapy. Photosensitizers (PSs) (essential ingredients in PDT) aggregate easily owing to their lipophilic properties. The aim of this study was to synthesise a PS (methyl pheophorbide a, MPa) and design a biocompatible lipid-based nanocarrier to improve its bioavailability and pharmacological effects. MPa-loaded nano-transfersomes were fabricated by sonication. The characteristics of synthesised PS and nano-transfersomes were assessed. The effects of PDT were evaluated by 1,3-diphenylisobenzofuran assay and by measuring photo-cytotoxicity against HeLa and A549 cell lines. The mean particle size and zeta potential for nano-transfersomes ranged from 95.84 to 267.53 nm and −19.53 to −45.08 mV, respectively. Nano-transfersomes exhibited sustained drug release for 48 h in a physiological environment (as against burst release in an acidic environment), which enables its use as a pH-responsive drug release system in PDT with enhanced photodynamic activity and reduced side effects. The formulations showed light cytotoxicity, but no dark toxicity, which meant that light irradiation resulted in anti-cancer effects. Additionally, formulations with the smallest size exhibited photodynamic activity to a larger extent than those with the highest loading capacity or free MPa. These results suggest that our MPa-loaded nano-transfersome system is a promising anti-cancer strategy for PDT.

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.

Liposome composition in drug delivery design, synthesis, characterization, and clinical application

Liposomal drug delivery represents a highly adaptable therapeutic platform for treating a wide range of diseases. Natural and synthetic lipids, as well as surfactants, are commonly utilized in the synthesis of liposomal drug delivery vehicles. The molecular diversity in the composition of liposomes enables drug delivery with unique physiological functions, such as pH response, prolonged blood circulation, and reduced systemic toxicity. Herein, we discuss the impact of composition on liposome synthesis, function, and clinical utility.

3D printed ocusert laden with ultra-fluidic glycerosomes of ganciclovir for the management of ocular cytomegalovirus retinitis

Cytomegalovirus (CMV) retinitisis a vision-threatening disease that principally afflicts immunosuppressed patients. For the management of the disease, Ganciclovir (GCV) is usually administered systemically, where patients may suffer severe untoward effects. The ocularly-applied alternatives are either the intravitreal injections, which are frequently administered due to GCV short half-life, or the sustained-release implants, which require surgical removal upon drug depletion. Both therapies are invasive and should be completed by a medical expert. The objective of this research was to formulate a non-invasive alternative represented in GCV loaded ultra-fluidic glycerosomes (UFGs), which are glycerosomes containing sodium taurocholate as an edge activator (EA), then incorporating the optimal UFGs in polylactic acid (PLA)-based 3D printed ocusert to prolong the release of GCV. The experimental design, the statistical analysis, and the optimization were performed via Design-Expert® software. The optimal formulation (UFGs 6; composed of 600 mg Phosphatidylcholine (PC), 20 mg cholesterol, 0.1:1 weight molar ratio of EA: PC and 1 gm glycerol) possessed nanovesicles (441.70 ± 1.13 nm) that entrapped 69.33 ± 0.28 % of GCV, with zeta potential value of -37.00 ± 0.42 mV and deformability index value of 74.68 ± 0.71. The confocal microscopy results showed the supreme penetration power of UFGs through the rabbit's cornea, compared to edge-activated vesicles and conventional glycerosomes from the laden ocusert. Moreover, the topical application of the ocusert laden with the optimal GCV loaded UFGs to the rabbits' eyes evidenced their safety as per the histopathological findings. Furthermore, a pharmacokinetic study in the rabbit's aqueous humor demonstrated the sustained release of GCV from the ocusert laden with the optimal GCV loaded UFGs over 5 days. Inclusively, the ocusert laden with UFGs could be considered as a non-invasive sustaining drug delivery system of GCV for the management of CMV retinitis.

Omega-3- and Resveratrol-Loaded Lipid Nanosystems for Potential Use as Topical Formulations in Autoimmune, Inflammatory, and Cancerous Skin Diseases

Resveratrol (RSV) and omega 3 (ω₃), because of their biological favorable properties, have become subjects of interest for researchers in dermocosmetic and pharmaceutical industries; however, these bioactives present technological limitations that hinder their effective delivery to the target skin layer. To overcome the stability and skin permeation limitations of free bioactives, this work proposes a combined strategy involving two different lipid nanosystems (liposomes and lipid nanoparticles) that include ω₃ in their lipid matrix. Additionaly, RSV is only encapsulated in liposomes that provid an adequate amphiphilic environment. Each formulation is thoroughly characterized regarding their physical–chemical properties. Subsequently, the therapeutic performance of the lipid nanosystems is evaluated based on their protective roles against lipid peroxidation, as well as inhibition of cicloxygenase (COX) and nitric oxid (NO) production in the RWA264.7 cell line. Finally, the lipid nanosystems are incorporated in hydrogel to allow their topical administration, then rheology, occlusion, and RSV release–diffusion assays are performed. Lipid nanoparticles provide occlusive effects at the skin surface. Liposomes provide sustained RSV release and their flexibility conferred by edge activator components enhances RSV diffusion, which is required to reach NO production cells and COX cell membrane enzymes. Overall, the inclusion of both lipid nanosystems in the same semisolid base constitutes a promising strategy for autoimmune, inflammatory, and cancerous skin diseases.

Vitamin D3/phospholipid complex decorated caseinate nanomicelles for targeted delivery of synergistic combination therapy in breast cancer

Targeted delivery of cytotoxic drugs has shown great potential in cancer therapy. In this light, vitamin D3 (vit.D3)-coated micelles were fabricated to encapsulate the cytotoxic drug; etoposide (ETP). Sodium caseinate micelles were first utilized to encapsulate vit.D3 and ETP within their hydrophobic core, then drug-loaded micelles were further decorated with an envelope of vit.D3/ phospholipid complex to enhance the active targeting potency of fabricated micelles via exploiting vit.D3 receptors (VDRs) overexpressed on the outer surface of breast cancer cells. In vitro cytotoxicity studies showed that fabricated micelles exhibited improved anticancer effect on MDA MB-231 and MCF-7 human breast cancer cell lines in comparison to free vit.D3 + ETP without any significant toxicity on normal human lung fibroblast (Wi-38) cells. In vivo biodistribution and efficacy studies in Ehrlich ascites tumor animal model revealed that fabricated micelles manifested improved accumulation in tumor tissue due to active targeting potential of vit.D3 without any remarkable toxicity. More importantly, fabricated micelles resulted in enhanced tumor apoptosis, reduced angiogenesis, invasion and autophagy, besides a decline in the tumor expression levels of both miR-21 and miR-192. Therefore, vit.D3/ETP micelles could serve as a favorable actively targeted anticancer delivery system having a superior effect over the free combination.

Experimental Design Based Optimization and Ex Vivo Permeation of Desmopressin Acetate Loaded Elastic Liposomes Using Rat Skin

The study aimed to develop elastic-liposome-based transdermal delivery of desmopressin acetate for enhanced permeation to control enuresis, central diabetes insipidus, and traumatic injury. Elastic liposomes (ELs)-loaded desmopressin acetate was prepared, optimized, and evaluated for improved transdermal permeation profiles using rat skin. Full factorial design with independent factors (X₁ for lipid and X₂ for surfactant) at three levels was used against four responses (Y₁, Y₂, Y₃, and Y₄) (dependent variables). Formulations were characterized for vesicle size, polydispersity index (PDI), zeta potential, % entrapment efficiency (% EE), in vitro drug release, in vitro hemolysis potential, ex vivo drug permeation and drug deposition (DD), and ex vivo vesicle–skin interaction using scanning electron microscopy studies. The optimized formulation ODEL1 based on desirability function was found to have vesicle size, % EE, % DR, and permeation flux values of 118.7 nm, 78.9%, 75.1%, and 5.3 µg/h·cm², respectively, which were close to predicted values. In vitro release profiles indicated slow and sustained delivery. Permeation flux values of ODEL1 and ODEL2 were 5.3 and 3.1 µg/h·cm², respectively, which are 7.5- and 4.4-fold higher as compared to DS (0.71 µg/h·cm²). The obtained flux was relatively higher than the clinical target value of the drug for therapeutic efficacy. Moreover, the DD value of ODEL1 was significantly higher than ODEL2 and DS. Hemocompatibility study confirmed safety concerns. Finally, vesicle–skin interaction corroborated mechanistic views of permeation through rat skin. Conclusively, the transdermal delivery may be a suitable alternative to oral and nasal delivery to treat nocturnal enuresis, central diabetes insipidus, hemophilia A and von Willebrand’s disease, and any traumatic injuries.

Ethosomes and Transethosomes for Mangiferin Transdermal Delivery

Mangiferin is a natural glucosyl xanthone with antioxidant and anti-inflammatory activity, making it suitable for protection against cutaneous diseases. In this study ethosomes and transethosomes were designed as topical delivery systems for mangiferin. A preformulation study was conducted using different surfactants in association with phosphatidylcholine. Vesicle dimensional distribution was monitored by photon correlation spectroscopy, while antioxidant capacity and cytotoxicity were respectively assessed by free radical scavenging analysis and MTT on HaCaT keratinocytes. Selected nanosystems were further investigated by cryogenic transmission electron microscopy, while mangiferin entrapment capacity was evaluated by ultracentrifugation and HPLC. The diffusion kinetics of mangiferin from ethosomes and transethosomes evaluated by Franz cell was faster in the case of transethosomes. The suitability of mangiferin-containing nanovesicles in the treatment of skin disorders related to pollutants was investigated, evaluating, in vitro, the antioxidant and anti-inflammatory effect of ethosomes and transethosomes on human keratinocytes exposed to cigarette smoke as an oxidative and inflammatory challenger. The ability to induce an antioxidant response (HO-1) and anti-inflammatory status (IL-6 and NF-kB) was determined by RT-PCR and immunofluorescence. The data demonstrated the effectiveness of mangiferin loaded in nanosystems to protect cells from damage. Finally, to gain insight into the keratinocytes’ uptake of ethosome and transethosome, transmission electron microscopy analyses were conducted, showing that both nanosystems were able to pass intact within the cells.

Identifying Underlying Issues Related to the Inactive Excipients of Transfersomes based Drug Delivery System

Transfersomes are bilayer vesicles composed of phospholipid and edge activators, which are mostly surfactant. Transfersomes based drug delivery system has gained a lot of interest of the pharmaceutical researchers for their ability to improve drug penetration and permeation through the skin. Transdermal drug delivery via transfersomes has the potential to overcome the challenge of low systemic availability. However, this complex vesicular system has different issues to consider for developing a successful transdermal delivery system. One of the major ingredients, phospholipid, has versatile sources and variable effect on the vesicle size and drug entrapment in transfersomes. The other one, termed as edge activators or surfactant, has some crucial consideration of skin damage and toxicity depending upon its type and concentration. A complex interaction between type and concentration of phospholipid and surfactant was observed, which affect the physicochemical properties of transfersomes. This review focuses on the practical factors related to these two major ingredients, such as phospholipid and surfactant. The origin, purity, desired concentration, the susceptibility of degradation, etc. are the important factors for selecting phospholipid. Regarding surfactants, the major aspects are type and desired concentration. A successful development of transfersomes based drug delivery system depends on the proper considerations of these factors and practical aspects.

Intriguing Biomedical Applications of Synthetic and Natural Cell-Derived Vesicles: A Comparative Overview

The significant role of a vesicle is well recognized; however, only lately has the advancement in biomedical applications started to uncover their usefulness. Although the concept of vesicles originates from cell biology, it later transferred to chemistry and material science to develop nanoscale artificial vesicles for biomedical applications. Herein, we examine different synthetic and biological vesicles and their applications in the biomedical field in general. As our understanding of biological vesicles increases, more suitable biomimicking synthetic vesicles will be developed. The comparative discussion between synthetic and natural vesicles for biomedical applications is a relevant topic, and we envision this could enable the development of a proper approach to realize the next-generation treatment goals.

Non-ionic surfactants as innovative skin penetration enhancers: insight in the mechanism of interaction with simple 2D stratum corneum model system

Transdermal drug delivery is a passive diffusion process of an active compound through the skin which is affected by drug solubility in the multilamellar lipidic matrix of the stratum corneum (SC). Widely used non-ionic surfactants (NIS) can be added into transdermal formulations to enhance the penetration of drugs by influencing the packing of the stratum corneum lipidic matrix. Objective of our study was to analyse the interaction between selected NIS and a simple SC lipidic matrix model system using a variety of surface-sensitive techniques based on the application of Langmuir monolayers. In this work, the well-known surfactant Polysorbate 80 was compared with a modern surfactant Sucrose monolaurate. Infrared reflection-absorption spectroscopy (IRRAS) and epifluorescence microscopy provide information about the effects of those surfactants on the SC model system. Monolayer isotherms of the SC model mixture indicate a very stiff and well-packed layer, however, packing defects are evidenced in epifluorescence studies. The injection of the two NIS underneath the SC monolayers proved their potential to penetrate into the SC model at the air-water interface having a maximum insertion pressure (MIP) above the assumed lateral pressure of biological membranes. The NIS adsorbed preferentially into packing defects seen in epifluorescence microscopy studies with Sucrose monolaurate being more active than Polysorbate 80 in disordering the SC monolayer.

Proniosomal Gel for Topical Delivery of Rutin: Preparation, Physicochemical Characterization and In Vitro Toxicological Profile Using 3D Reconstructed Human Epidermis Tissue and 2D Cells

Rutin (Rut) is a natural flavonol, well-known for its broad-spectrum of therapeutic effects, including antioxidant and antitumoral activities; still, it has a reduced clinical outcome due to its limited solubility in aqueous solutions. To overcome this drawback, this study proposes a novel formulation for rutin as a proniosomal gel for cutaneous applications. The gel was prepared by coacervation phase-separation method and complies with the standard requirements in terms of particle size (140.5 ± 2.56 nm), zeta potential (−27.33 ± 0.09 mV), encapsulation capacity (> 50%), pH (7.002 ± 0.18) and rheological properties. The results showed high biocompatibility of the gel on the 3D reconstructed human epidermis model characterized by increased viability of the cells and a lack of irritant and phototoxic potential. The evaluations on 2D cells confirm the preferential cytotoxic effect of Rut on melanoma cells (IC₅₀ value = 8.601 µM, nuclear fragmentation) compared to normal keratinocytes. Our data suggest that the proniosomal gel is a promising drug carrier for Rut in the management and prevention of skin disorders.

Ratite oils for local transdermal therapy of 4-OH tamoxifen: development, characterization, and ex vivo evaluation

The anti-inflammatory property of ratite oils as well as its ability to act as a penetration enhancer makes it an ideal agent to be used in transdermal formulations. The present study aims to develop an effective transfersomal delivery of 4-hydroxytamoxifen (4-OHT), an anti-cancer drug, using ratite oil as a carrier agent for the treatment of breast cancer (BC). The 4-OHT transfersomes were prepared with and without ratite oils using soy phosphatidylcholine and three different edge activators (EAs) in five different molar ratios using the rotary evaporation-ultrasonication method. Optimal transfersome formulations were selected using physical-chemical characterization and ex vivo studies. Results from physical-chemical characterization of the developed formulations found sodium taurocholate to be the most suitable EA, which recorded highest entrapment efficiency of 95.1 ± 2.70% with 85:15, (w/w) and lowest vesicle size of 82.3 ± 0.02 nm with 75:25, (w/w) molar ratios. TEM and DSC studies showed that the vesicles were readily identified and present in a nearly perfect spherical shape. In addition, formulations with emu oil had better stability than formulations with ostrich oil. Physical stability studies at 4 °C showed that ratite oil transfersomes were stable up to 4 weeks, while transfersomes without ratite oils were stable for 8 weeks. Ex vivo permeability studies using porcine skin concluded that 4-OHT transfersomal formulations with (85:15, w/w) without emu oil have the potential to be used in transdermal delivery approach to enhance permeation of 4-OHT, which may be beneficial in the treatment of BC.

Lipid Drug Carriers for Cancer Therapeutics: An Insight into Lymphatic Targeting, P-gp, CYP3A4 Modulation and Bioavailability Enhancement

In the treatment of cancer, chemotherapy plays an important role though the efficacy of anti-cancer drug administered orally is limited, due to their poor solubility in physiological medium, inability to cross biological membrane, high Para-glycoprotein (P-gp) mediated drug efflux, and pre-systemic metabolism. These all factors cumulatively reduce drug exposure at the target site leading to multidrug resistance (MDR). Lipid based carriers systems has been explored to overcome solubility and permeability related issues of anti-cancer drugs. The lipid based formulations have also been reported to circumvent the effect of P-gp and CYP3A4. Further long chain triglycerides (LCT) has shown their ability to access Lymphatic route over Medium Chain Triglycerides, as the former has been extensively used for targeting anti-cancer drugs at proliferating cells through lymphatic route. Therefore this review tries to reflect the usefulness of lipid based drug carriers systems (viz. liposome, solid lipid nanoparticle, nano-lipid carriers, self-emulsifying, lipidic pro-drugs) in targeting lymphatic system and overcoming issues related to solubility and permeability of anti-cancer drugs. Moreover, we have also tried to reflect how critically lipid based carriers are important in maximizing therapeutic safety and efficacy of anti-cancer drugs.

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

Aim

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

Methods

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

Results

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

Conclusion

ETH9-INV8 is a promising transdermal system for VRD.

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.

Transdermal delivery systems in cosmetics

Transdermal delivery systems have been intensively studied over the past 2 decades, with the focus on overcoming the skin barrier for more effective application of pharmaceutical and cosmetic products. Although the cosmeceutical industry has made a substantial progress in the development and incorporation of new and effective actives in their products, the barrier function of the skin remains a limiting factor in the penetration and absorption of these actives. Enhancement via modification of the stratum corneum by hydration, acting of chemical enhancers on the structure of stratum corneum lipids, and partitioning and solubility effects are described. This review summarizes the advances in the development and mechanisms of action of chemical components that act as permeation enhancers, as well as the advances in appropriate vehicles, such as gels, emulsions, and vesicular delivery systems, that can be used for effective transdermal delivery.

Transferosomes as nanocarriers for drugs across the skin: Quality by design from lab to industrial scale

Transferosomes, also known as transfersomes, are ultradeformable vesicles for transdermal applications consisting of a lipid bilayer with phospholipids and an edge activator and an ethanol/aqueous core. Depending on the lipophilicity of the active substance, it can be encapsulated within the core or amongst the lipid bilayer. Compared to liposomes, transferosomes are able to reach intact deeper regions of the skin after topical administration delivering higher concentrations of active substances making them a successful drug delivery carrier for transdermal applications. Most transferosomes contain phosphatidylcholine (C18) as it is the most abundant lipid component of the cell membrane, and hence, it is highly tolerated for the skin, decreasing the risk of undesirable effects, such as hypersensitive reactions. The most common edge activators are surfactants such as sodium deoxycholate, Tween® 80 and Span® 80. Their chain length is optimal for intercalation within the C18 phospholipid bilayer. A wide variety of drugs has been successfully encapsulated within transferosomes such as phytocompounds like sinomenine or apigenin for rheumatoid arthritis and leukaemia respectively, small hydrophobic drugs but also macromolecules like insulin. The main factors to develop optimal transferosomal formulations (with high drug loading and nanometric size) are the optimal ratio between the main components as well as the critical process parameters for their manufacture. Application of quality by design (QbD), specifically design of experiments (DoE), is crucial to understand the interplay among all these factors not only during the preparation at lab scale but also in the scale-up process. Clinical trials of a licensed topical ketoprofen transferosomal gel have shown promising results in the alleviation of symptons in orthreothritis with non-severe skin and subcutaneous tissue disorders. However, the product was withdrawn from the market which probably was related to the higher cost of the medicine linked to the expensive manufacturing process required in the production of transferosomes compared to other conventional gel formulations. This example brings out the need for a careful formulation design to exploit the best properties of this drug delivery system as well as the development of manufacturing processes easily scalable at industrial level.

Stabilization of Deformable Nanovesicles Based on Insulin-Phospholipid Complex by Freeze-Drying

Deformable nanovesicles have been extensively investigated due to their excellent ability to penetrate biological barriers. However, suffering from serious physical and chemical instabilities, the wide use of deformable nanovesicles in medical applications is still limited. Moreover, far less work has been done to pursue the lyophilization of deformable nanovesicles. Here, we aimed to obtain stable deformable nanovesicles via freeze-drying technology and to uncover the underlying protection mechanisms. Firstly, the density of nanovesicles before freeze-drying, the effect of different kinds of cryoprotectants, and the types of different reconstituted solvents after lyophilization were investigated in detail to obtain stable deformable nanovesicles based on insulin-phospholipid complex (IPC-DNVs). To further investigate the underlying protection mechanisms, we performed a variety of analyses. We found that deformable nanovesicles at a low density containing 8% lactose and trehalose in a ratio of 1:4 (8%-L-T) have a spherical shape, smooth surface morphology in the lyophilized state, a whorl-like structure, high entrapment efficiency, and deformability after reconstitution. Importantly, the integrity of IPC, as well as the secondary structure of insulin, were well protected. Accelerated stability studies demonstrated that 8%-L-T remained highly stable during storage for 6 months at 25 °C. Based on in vivo results, lyophilized IPC-DNVs retained their bioactivity and had good efficacy. Given the convenience of preparation and long term stability, the use of combined cryoprotectants in a proper ratio to protect stable nanovesicles indicates strong potential for industrial production.

Bilosomes as a novel carrier for the cutaneous delivery for dapsone as a potential treatment of acne: preparation, characterization and in vivo skin deposition assay

In our study, the potential of bilosomes as novel vesicular carrier for the cutaneous delivery of the sulphone compound, Dapsone, for topical treatment of acne was investigated. The effect of different formulation variables (type and concentration of bile salt, and molar ratio of Span 60:cholesterol) on the properties of DPS-loaded bilosomes was investigated using a full factorial design. Design Expert software was used for data analysis and optimization of DPS-loaded bilosomes. The optimized bilosomes, chosen on the basis of their superior properties giving maximum entrapment, in vitro release after different time intervals and RE% with minimum vesicle size. Results showed that the bilosome system prepared using Span^® 60: Cholesterol (5:1) and containing 0.25 M sodium deoxycholate as the bile salt was found to obey these criteria, with a desirability value of 0.637. Therefore, this system was chosen for further assessment for its morphological properties, zeta potential, thermal analysis using differential scanning calorimetry and X-ray diffractometry. Results revealed that the chosen bilosomes were spherical in shape with no aggregation, and contained DPS in a molecularly dispersed amorphous form. Finally, the capability of the optimized DPS-loaded bilosomes to deliver DPS through rat skin layers will be investigated and compared with that of DPS alcoholic solution. Results showed that the amounts of DPS retained in the skin treated with DPS-loaded bilosomes, and DPS alcoholic solution after 24 h were found to be 170.57 ± 55.12 and 120.24 ± 10.7 µg/mL, respectively, representing about 1.5-fold higher drug retained in the bilosomes-treated skin. Finally, the safety and the tolerability of the prepared bilosomes were assessed using histopathological examination, and revealed that the control untreated skin sections and skin sections treated with DPS-loaded bilosomes showed normal histological structures characterized by absence of defects or inflammation. Such results can be considered a good addition in the field of pharmaceutical drug delivery for effective topical therapy of acne.

Transdermal patches: Design and current approaches to painless drug delivery

Use of transdermal patches can evade many issues associated with oral drug delivery, such as first-pass hepatic metabolism, enzymatic digestion attack, drug hydrolysis and degradation in acidic media, drug fluctuations, and gastrointestinal irritation. This article reviews various transdermal patches available in the market, types, structural components, polymer role, and the required assessment tools. Although transdermal patches have medical applications for smoking cessation, pain relief, osteoporosis, contraception, motion sickness, angina pectoris, and cardiac disorders, advances in formulation development are ongoing to make transdermal patches capable of delivering more challenging drugs. Transdermal patches can be tailored and developed according to the physicochemical properties of active and inactive components, and applicability for long-term use. Therefore, a number of chemical approaches and physical techniques for transdermal patch development are under investigation.

The anti MRSA biofilm activity of Thymus vulgaris essential oil in nanovesicles

BACKGROUND

Thymus vulgaris essential oil (T) could be an alternative to classical antibiotics against bacterial biofilms, which show increased tolerance to antibiotics and host defence systems and contribute to the persistence of chronic bacterial infections.

HYPOTHESIS

A nanovesicular formulation of T may chemically protect the structure and relative composition of its multiple components, potentially improving its antibacterial and antibiofilm activity.

STUDY DESIGN

We prepared and structurally characterized T in two types of nanovesicles: nanoliposomes (L80-T) made of Soybean phosphatidylcholine (SPC) and Polysorbate 80 (P80) [SPC:P80:T 1:0.75:0.3 w:w], and nanoarchaeosomes (A80-T) made of SPC, P80 and total polar archaeolipids (TPA) extracted from archaebacteria Halorubrum tebenquichense [SPC:TPA:P80:T 0.5:0.50.75:0.7 w:w]. We determined the macrophage cytotoxicity and the antibacterial activity against Staphylococcus aureus ATCC 25,923 and four MRSA clinical strains.

RESULTS

L80-T (Z potential -4.1 ± 0.6 mV, ∼ 115 nm, ∼ 22 mg/ml T) and A80-T (Z potential -6.6 ± 1.5 mV, ∼ 130 nm, ∼ 42 mg/ml T) were colloidally and chemically stable, maintaining size, PDI, Z potential and T concentration for at least 90 days. While MIC₉₀ of L80-T was > 4 mg/ml T, MIC₉₀ of A80-T was 2 mg/ml T for all S. aureus strains. The antibiofilm formation activity was maximal for A80-T, while L80-T did not inhibit biofilm formation compared to untreated control. A80-T significantly decreased the biomass of preformed biofilms of S. aureus ATCC 25,923 strain and of 3 of the 4 clinical MRSA isolates at 4 mg/ml T. It was found that the viability of J774A.1 macrophages was decreased significantly upon 24 h incubation with A80-T, L80-T and T emulsion at 0.4 mg/ml T. These results show that from 0.4 mg/ml T, a value lower than MIC₉₀ and the one displaying antibiofilm activity, with independence of its formulation, T significantly decreased the macrophages viability.

CONCLUSION

Overall, because of its lower MIC₉₀ against planktonic bacteria, higher antibiofilm formation capacity and stability during storage, A80-T resulted better antibacterial agent than T emulsion and L80-T. These results open new avenues to explode the A80-T antimicrobial intracellular activity.

Liposomes for delivery of antioxidants in cosmeceuticals: Challenges and development strategies

Antioxidants (AOs) play a crucial role in the protection and maintenance of health and are also integral ingredients in beauty products. Unfortunately, most of them are sensitive due to their instability and insolubility. The use of liposomes to protect AOs and expand their applicability to cosmeceuticals, thereby, is one of the most effective solutions. Notwithstanding their offered advantages for the delivery of AOs, liposomes, in their production and application, present many challenges. Here, we provide a critical review of the major problems complicating the development of liposomes for AO delivery. Along with issues related to preparation techniques and encapsulation efficiency, the loss of protective function and inefficiency of skin permeability are the main disadvantages of liposomes. Corresponding development strategies for resolving these problems, with their respective advantages and drawbacks, are introduced, discussed in some depth, and summarized in these pages as well. Advanced liposomes have a vital role to play in the development and delivery of AOs in practical cosmeceutical product applications.