Glycerosomes: Use of hydrogenated soy phosphatidylcholine mixture and its effect on vesicle features and diclofenac skin penetration

Lipid-based nanoparticles as a promising treatment for the skin cancer

The prevalence of skin disorders, especially cancer, is increasing worldwide. Several factors are involved in causing skin cancer, but ultraviolet (UV) light, including sunlight and tanning beds, are considered the leading cause. Different methods such as chemotherapy, radiotherapy, cryotherapy, and photodynamic therapy are mostly used for the skin cancer treatment. However, drug resistance and toxicity against cancer cells are related to these treatments. Lipid-nanoparticles have attracted significant interest as delivery systems due to non-invasive and targeted delivery based on the type of active drug. However, the stratum corneum, the outer layer of the skin, is inherently impervious to drugs. Due to their ability to penetrate the deep layers of the skin, skin delivery systems are capable of delivering drugs to target cells in a protected manner. The aim of this review was to examine the properties and applications of nanoliposomes used in the treatment and prevention of numerous types of skin cancer.

Preparation, characterization, and ex-vivo evaluation of curcumin-loaded niosomal nanoparticles on the equine sperm quality during cooled storage

Oxidative damage to sperm during cooled storage is a significant issue, and curcumin, with its antioxidant properties, could be a solution. However, its low bioavailability presents a challenge that this study aims to address. The primary objective of this study was to investigate the potential of curcumin-loaded niosomal nanoparticles (Cur-LNN) to enhance the antioxidant properties of curcumin and its effect on sperm quality during 72 h cooled storage. The thin-film hydration procedure was applied to prepare Cur-LNN. The fabricated noisomal nanocarriers were characterized using dynamic light scattering (DLS), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), and Fourier-transform infrared (FT-IR) spectroscopy. Moreover, the encapsulation and loading efficiency, in vitro release study, and ex-vivo antioxidant functionality of Cur-LNN on the stallion sperm preserved under cooled storage conditions were assessed. The fabricated Cur-LNN was spherical in shape and had an average particle size of 163.1 ± 1.8 nm, a zeta potential of -34.1 ± 1.9 mV, a poly-dispersity index of 0.339 ± 0.045, an encapsulation efficiency of 92.34 ± 0.18 %, and a loading efficiency of 35.57 ± 1.36 %. Ex-vivo evaluation revealed that supplementation of the semen extender with Cur-LNN has the potential to enhance sperm quality by improving total and progressive motility, plasma membrane functionality, and lipid peroxidation. These results demonstrate that Cur-LNN exhibited stronger antioxidant and protective effects than curcumin. Although further in vivo investigations are warranted, our ex-vivo results suggest that Cur-LNN has the potential to attenuate oxidative damage and can be used to fortify the antioxidant capacity of equine semen under cooled storage conditions.

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.

Synergistic approach for acne vulgaris treatment using glycerosomes loaded with lincomycin and lauric acid: Formulation, in silico, in vitro, LC-MS/MS skin deposition assay and in vivo evaluation

This study aims to develop a pharmaceutical formulation that combines the potent antibacterial effect of lincomycin and lauric acid against Cutibacterium acnes (C. acnes), a bacterium implicated in acne. The selection of lauric acid was based on an in silico study, which suggested that its interaction with specific protein targets of C. acnes may contribute to its synergistic antibacterial and anti-inflammatory effects. To achieve our aim, glycerosomes were fabricated with the incorporation of lauric acid as a main constituent of glycerosomes vesicular membrane along with cholesterol and phospholipon 90H, while lincomycin was entrapped within the aqueous cavities. Glycerol is expected to enhance the cutaneous absorption of the active moieties via hydrating the skin. Optimization of lincomycin-loaded glycerosomes (LM-GSs) was conducted using a mixed factorial experimental design. The optimized formulation; LM-GS4 composed of equal ratios of cholesterol:phospholipon90H:Lauric acid, demonstrated a size of 490 ± 17.5 nm, entrapment efficiency-values of 90 ± 1.4 % for lincomycin, and97 ± 0.2 % for lauric acid, and a surface charge of -30.2 ± 0.5mV. To facilitate its application on the skin, the optimized formulation was incorporated into a carbopol hydrogel. The formed hydrogel exhibited a pH value of 5.95 ± 0.03 characteristic of pH-balanced skincare and a shear-thinning non-Newtonian pseudoplastic flow. Skin deposition of lincomycin was assessed using an in-house developed and validated LC-MS/MS method employing gradient elution and electrospray ionization detection. Results revealed that LM-GS4 hydrogel exhibited a two-fold increase in skin deposition of lincomycin compared to lincomycin hydrogel, indicating improved skin penetration and sustained release. The synergistic healing effect of LM-GS4 was evidenced by a reduction in inflammation, bacterial load, and improved histopathological changes in an acne mouse model. In conclusion, the proposed formulation demonstrated promising potential as a topical treatment for acne. It effectively enhanced the cutaneous absorption of lincomycin, exhibited favorable physical properties, and synergistic antibacterial and healing effects. This study provides valuable insights for the development of an effective therapeutic approach for acne management.

Simultaneous Detection of Two Extracellular Vesicle Subpopulations in Saliva Assisting Tumor T Staging of Oral Squamous Cell Carcinoma

Extracellular vesicles (EVs), acting as important mediators of intercellular communication, play an essential role in physiological processes, which have unique potential in the medical field. However, the heterogeneity of EVs limits their development for disease diagnosis and therapy, making the EV subpopulation analysis extremely valuable. In this article, a simple microfluidic approach was presented for the on-chip specific isolation and detection of two phenotypes of EVs (Annexin V⁺ EGFR⁺ EVs and Annexin V^- EGFR⁺ EVs) based on different biomolecule-modified magnetic nanospheres and a fluorescence labeling technique. Combined with the control of the magnetic field in the microzone and fluid flow, it was easy to form two separate functional regions in the chip to capture different EV subpopulations. This method was successfully applied to the tests of clinical saliva samples in 75 oral squamous cell carcinoma (OSCC) patients and 10 healthy people. The results showed that the total level of EGFR⁺ EVs was much higher in OSCC patients that in healthy people. Meantime, the ratio of Annexin V⁺ EGFR⁺ EVs to Annexin V^- EGFR⁺ EVs was found to be negatively correlated with tumor T stage of OSCC patients with a statistical difference, which suggested the ratio as a clinical index for monitoring the progression of OSCC in real time based on a noninvasive method. The approach provided a novel idea for evaluating the tumor T stage of OSCC and a powerful tool for clinical application.

Skin drug delivery using lipid vesicles: A starting guideline for their development

Lipid vesicles can provide a cost-effective enhancement of skin drug absorption when vesicle production process is optimised. It is an important challenge to design the ideal vesicle, since their properties and features are related, as changes in one affect the others. Here, we review the main components, preparation and characterization methods commonly used, and the key properties that lead to highly efficient vesicles for transdermal drug delivery purposes. We stand by size, deformability degree and drug loading, as the most important vesicle features that determine the further transdermal drug absorption. The interest in this technology is increasing, as demonstrated by the exponential growth of publications on the topic. Although long-term preservation and scalability issues have limited the commercialization of lipid vesicle products, freeze-drying and modern escalation methods overcome these difficulties, thus predicting a higher use of these technologies in the market and clinical practice.

Centella asiatica extract-SiO2 nanocomposite: More than a drug-delivery system for skin protection from oxidative damage

An innovative nanotechnology-based approach was used for the preparation of Centella asiatica (C. asiatica) extract-SiO2 nanocomposites, specifically tailored for skin protection from oxidative damage. Different amounts of C. asiatica glycolic extract (1.0, 3.0, 5.0, and 10.0 wt %) and fumed silica were used to prepare the nanocomposites by means of ball milling method. The influence of both composition of the starting mixture and milling time on the final products was evaluated by different techniques such as X-ray powder diffraction, scanning electron microscopy, infrared spectroscopy, thermogravimetric analysis, and nitrogen sorption analysis. Results confirmed the integrity of the natural extract after the milling process, and its successful loading in the silica matrix. No cytotoxicity was observed for the obtained nanocomposites, which showed high in-vitro ability to scavenge 2,2-diphenyl-1-picrylhydrazyl and to protect human keratinocytes from damages induced with hydrogen peroxide.

Current Advances in Lipid Nanosystems Intended for Topical and Transdermal Drug Delivery Applications

Skin delivery is an exciting and challenging field. It is a promising approach for effective drug delivery due to its ease of administration, ease of handling, high flexibility, controlled release, prolonged therapeutic effect, adaptability, and many other advantages. The main associated challenge, however, is low skin permeability. The skin is a healthy barrier that serves as the body's primary defence mechanism against foreign particles. New advances in skin delivery (both topical and transdermal) depend on overcoming the challenges associated with drug molecule permeation and skin irritation. These limitations can be overcome by employing new approaches such as lipid nanosystems. Due to their advantages (such as easy scaling, low cost, and remarkable stability) these systems have attracted interest from the scientific community. However, for a successful formulation, several factors including particle size, surface charge, components, etc. have to be understood and controlled. This review provided a brief overview of the structure of the skin as well as the different pathways of nanoparticle penetration. In addition, the main factors influencing the penetration of nanoparticles have been highlighted. Applications of lipid nanosystems for dermal and transdermal delivery, as well as regulatory aspects, were critically discussed.

Optimized D-α-tocopherol polyethylene glycol succinate/phospholipid self-assembled mixed micelles: A promising lipid-based nanoplatform for augmenting the antifungal activity of fluconazole

Fluconazole (FLZ) is the most widely used antifungal agent for treating cutaneous candidiasis. Although oral FLZ has been proved to be effective, the incidence of side effects necessitates the development of an effective formulation that could surpass the pitfalls associated with systemic availability. Accordingly, this research aimed at developing a self-assembled mixed micelles topical delivery system to enhance the topical delivery of the drug. Self-assembled mixed micelles were developed using D-α-tocopheryl polyethylene glycol 1000 succinate and phospholipids and optimized using Box-Behnken design. The optimized formulation with minimized size was then tested in vivo for the antifungal activity against C. albicans in immunocompromised mice. Treatment with the optimized formulation led to decreased peripheral erythema as well as lesions due to fungal infection in comparison to raw FLZ loaded gel. Therefore, the developed formulation was found to be a promising vehicle for the treatment of cutaneous candidiasis.

Stability of Non-Ionic Surfactant Vesicles Loaded with Rifamycin S

These days, the eradication of bacterial infections is more difficult due to the mechanism of resistance that bacteria have developed towards traditional antibiotics. One of the medical strategies used against bacteria is the therapy with drug delivery systems. Non-ionic vesicles are nanomaterials with good characteristics for encapsulating drugs, due to their bioavailability and biodegradability, which allow the drugs to reach the specific target and reduce their side effects. In this work, the antibiotic Rifamycin S was encapsulated. The rifamycin antibiotics family has been widely used against Mycobacterium tuberculosis, but recent studies have also shown that rifamycin S and rifampicin derivatives have bactericidal activity against Staphylococcus epidermidis and Staphylococcus aureus. In this work, a strain of S. aureus was selected to study the antimicrobial activity through Minimum Inhibitory Concentration (MIC) assay. Three formulations of niosomes were prepared using the thin film hydration method by varying the composition of the aqueous phase, which included MilliQ water, glycerol solution, or PEG400 solution. Niosomes with a rifamycin S concentration of 0.13 μg/g were satisfactorily prepared. Nanovesicles with larger size and higher encapsulation efficiency (EE) were obtained when using glycerol and PEG400 in the aqueous media. Our results showed that niosomes consisting of an aqueous glycerol solution have higher stability and EE across a diversity of temperatures and pHs, and a lower MIC of rifamycin S against S. aureus.

New Vehiculation Systems of Mometasone Furoate for the Treatment of Inflammatory Skin Diseases

A pre-formulation study was carried out to obtain liposomal formulations of mometasone furoate as an alternative system to marketed forms of corticosteroid for the treatment of inflammatory skin lesions. Mometasone furoate was loaded in glycerosomes and glyceroethosomes, which were also modified with hyaluronic acid (glyceroethohyalurosomes). Vesicles were designed, elaborated, and characterized, and their biocompatibility, efficacy against oxidative stress and skin lesions were assessed in vitro, in human epidermal cells, and in vivo, in a mouse skin epidermal hyperplasia model. All formulations tested showed great encapsulation efficiency, nanometric size, formed monodispersed systems and a highly negative Z potential. Similar values were obtained over nine months storage at 4 °C, which indicates the great stability of the three types of nanoliposomes at least during the time tested. Among them, 0.1% mometasone furoate glyceroethohyalurosomes were the best formulation to protect cells against oxidative stress and their anti-inflammatory efficacy was confirmed in vivo, being even more effective than the marketed form (Elocom^®), as the reduction in the inflammation was even ~15% higher than that achieved with the commercial cream. Selected formulations could be potential candidates as new vehiculation systems for mometasone furoate. The presence of hyaluronic acid in glyceroethohyalurosomes makes them the best candidates in preventing/treating skin inflammatory lesions.

Glycerosomal thermosensitive in situ gel of duloxetine HCl as a novel nanoplatform for rectal delivery: in vitro optimization and in vivo appraisal

Duloxetine HCl (DXH) is a reuptake inhibitor of serotonin and norepinephrine used to treat the major depressive disorder. Following its extensive hepatic metabolism, acid-labile nature, and limited aqueous solubility, DXH has poor oral bioavailability (40%). The rectal route has been suggested as another route of administration to surmount such challenges. The present study aimed to prepare DXH-loaded glycerosomal (DXH-GLYS) in situ gel for rectal administration to increase DXH permeability and improve its bioavailability. Box-Behnken design (BBD) was adopted to prepare and optimize nanoglycerosomes. The impact of Phospholipon 90G (PL90G), Tween 80 concentrations, and glycerol percentage on encapsulation efficiency, nanoglycerosomal size, % cumulative DXH released, and the cumulative DXH permeated per unit area after 24 h were studied by the design. The pharmacokinetic and pharmacodynamic behavior of optimized formulation was investigated in rats. The formulated DXH-GLYS had a vesicle size ranging between 135.9 and 430.6 nm and an entrapment efficiency between 69.11 and 98.12%. The permeation experiment revealed that the optimized DXH-GLYS in situ gel increased DXH permeation by 2.62-fold compared to DXH solution. Pharmacokinetics studies disclosed that the DXH-GLYS in situ rectal gel exhibited 2.24-times increment in DXH bioavailability relative to oral DXH solution. The pharmacodynamic study revealed that the DXH-GLYS rectal treatment significantly improved the behavioral analysis parameters and was more efficacious as an antidepressant than the oral DXH solution. Collectively, these findings demonstrate that GLYS can be considered a potentially valuable rectal nanocarrier that could boost the DXH efficacy.

Optimizing glycerosome formulations via an orthogonal experimental design to enhance transdermal triptolide delivery

Triptolide exerts strong anti-inflammatory and immunomodulatory effects; however, its oral administration might be associated with side effects. Transdermal administration can improve the safety of triptolide. In this study, glycerosomes were prepared as the transdermal vehicle to enhance the transdermal delivery of triptolide. With entrapment efficiency and drug loading as dependent variables, the glycerosome formulation was optimized using an orthogonal experimental design. Phospholipid-to-cholesterol and phospholipid-to-triptolide mass ratios of 30:1 and 5:1, respectively and a glycerol concentration of 20 % (V/V) were used in the optimization. The glycerosomes prepared with the optimized formulation showed good stability, with an average particle size of 153.10 ± 2.69 nm, a zeta potential of -45.73 ± 0.60 mV and an entrapment greater than 75 %. Glycerosomes significantly increased the transdermal delivery of triptolide compared to conventional liposomes. As efficient carriers for the transdermal delivery of drugs, glycerosomes can potentially be used as an alternative to oral triptolide administration.

Mouthwash Formulation Co-Delivering Quercetin and Mint Oil in Liposomes Improved with Glycol and Ethanol and Tailored for Protecting and Tackling Oral Cavity

The aim of this work was the simultaneous loading of quercetin and mint essential oil (mint oil) in phospholipid vesicles specifically tailored to obtain an antibacterial and antioxidant mouthwash. The vesicles were prepared using soy lecithin and Tween 80 as bilayer components, and a mixture of phosphate buffer solution (33%), propylene glycol (33%) and ethanol (33%) as dispersing phase. The formation of regularly shaped, spherical and unilamellar vesicles was confirmed by cryogenic transmission electron microscopy analyses. Similarly, light scattering results disclosed that the size of the vesicles increased by increasing the concentration of mint oil, but at the same time the high amount of mint oil ensured high stability, as the size of these vesicles remained unchanged during 12 months of storage. All tested formulations were highly biocompatible towards epithelial cells and capable of counteracting oxidative cell damages caused by hydrogen peroxide. Moreover, the vesicles prepared with the highest concentration of mint oil inhibited the proliferation of the cariogenic Streptococcus mutans (S. mutans) and Lactobacillus acidophilus (L. acidophilus).

Multicompartment systems: A putative carrier for combined drug delivery and targeting

In this review, we discuss recent developments in multicompartment systems commonly referred to as vesosomes, as well as their method of preparation, surface modifications, and clinical potential. Vesosomal systems are able to entrap more than one drug moiety and can be customized for site-specific delivery. We focus in particular on the possible reticuloendothelial system (RES) - mediated accumulation of vesosomes, and their application in tumor targeting, as areas for further investigation.

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.

Oleuropein multicompartment nanovesicles enriched with collagen as a natural strategy for the treatment of skin wounds connected with oxidative stress

Aim: Collagen-enriched transfersomes, glycerosomes and glytransfersomes were specifically tailored for skin delivery of oleuropein. Methods: Vesicles were prepared by direct sonication and their main physicochemical and technological properties were measured. Biocompatibility, protective effect and promotion of the healing of a wounded cell monolayer were tested in vitro using fibroblasts. Results: Vesicles were mainly multicompartment, small (∼108 nm), slightly polydispersed (approximately 0.27) and negatively charged (~-49 mV). Oleuropein was incorporated in high amounts (approximately 87%) and vesicles were stable during four months of storage. In vitro studies confirmed the low toxicity of formulations (viability ≥95%), their effectiveness in counteracting nitric oxide generation and damages caused by free oxygen radicals, especially when collagen glytransfersomes were used (viability ~100%). These vesicles also promoted the regeneration of a wounded area by promoting the proliferation and migration of fibroblasts. Conclusion: Collagen-enriched vesicles are promising formulations capable of speeding up the healing of the wounded skin.

Ultradeformable vesicles: concepts and applications relating to the delivery of skin cosmetics

Skin aging is a phenomenon resulting in reduced self-confidence, thus becoming a major factor in social determinants of health. The use of active cosmetic ingredients can help prevent skin aging. Transfersomes are well known to be capable of deeply penetrating the dermis. This scoping review provides an insight into transfersomes and their prospective use in anti-aging cosmetics. Numerous reports exist highlighting the successful skin delivery of therapeutic agents such as high-molecular-weight, poorly water soluble and poorly permeable active ingredients by means of transfersomes. Moreover, in vitro and in vivo studies have indicated that transfersomes increase the deposition, penetration and efficacy of active ingredients. However, the use of transfersomes in the delivery of active cosmetic ingredients is limited. Considering their similar physicochemical properties, transfersomes should possess considerable potential as a delivery system for anti-aging cosmetics.

Extraction of the antioxidant phytocomplex from wine-making by-products and sustainable loading in phospholipid vesicles specifically tailored for skin protection

The present study is aimed at valorizing grape pomace, one of the most abundant winery-making by-products of the Mediterranean area, through the extraction of the main bioactive compounds from the skin of grape pomace and using them to manufacture innovative nanoformulations capable of both avoiding skin damages and promoting skincare. The phytochemicals were recovered through maceration in hydroethanolic solution. Catechin, quercetin, fisetin and gallic acid, which are known for their antioxidant power, were detected as the main compounds of the extract. Liposomes and phospholipid vesicles modified with glycerol or Montanov 82® or a combination of both, were used as carriers for the extract. The vesicles were small (~183 nm), slightly polydispersed (PI ≥ 0.28), and highly negatively charged (~-50 mV). The extract was loaded in high amounts in all vesicles (~100%) irrespective of their composition. The antioxidant activity of the extract, measured by using the DPPH (2,2-Diphenyl-1-picrylhydrazyl) test, was 84 ± 1%, and slightly increased when loaded into the vesicles (~89%, P < 0.05). The grape pomace extract loaded vesicles were highly biocompatible and able to protect fibroblasts (3T3) from the oxidative stress induced by hydrogen peroxide.

Nasal Spray Formulations Based on Combined Hyalurosomes and Glycerosomes Loading Zingiber officinalis Extract as Green and Natural Strategy for the Treatment of Rhinitis and Rhinosinusitis

A total green nanotechnological nasal spray has been manufactured and proposed as an alternative treatment of rhinitis and rhinosinusitis. It was obtained by combining the strengthening effect of liposomes on barrier function, the hydrating and lubricating properties of sodium hyaluronan and the anti-inflammatory and antioxidant activities of the extract of Zingiber officinalis. To this purpose, the extract was loaded in special phospholipid vesicles immobilized with hyaluronic acid (hyalurosomes), which were further enriched with glycerol in the water phase. Liposomes and glycerosomes were prepared as well and used as reference. Vesicles were oligolamellar and multicompartment, as confirmed by cryogenic transmission electron microscopy (cryo-TEM) observation, small in size (~140 nm) and negatively charged (~−23 mV). Spray characteristics were evaluated by using the Spraytec^® and instant images, from which the plume angle was measured. The range of the droplet size distribution and the narrow spray angle obtained suggest a good nebulization and a possible local deposition in the nasal cavity. In vitro studies performed by using human keratinocytes confirmed the high biocompatibility of vesicles and their ability to effectively counteract oxidative damage on cells induced by hydrogen peroxide. The overall collected data suggest that our vesicles are suitable as nasal spray.

Nanotechnology for Natural Medicine: Formulation of Neem Oil Loaded Phospholipid Vesicles Modified with Argan Oil as a Strategy to Protect the Skin from Oxidative Stress and Promote Wound Healing

Neem oil, a plant-derived product rich in bioactives, has been incorporated in liposomes and hyalurosomes modified by adding argan oil and so called argan-liposomes and argan-hyalurosomes. Argan oil has also been added to the vesicles because of its regenerative and protective effects on skin. In the light of this, vesicles were specifically tailored to protect the skin from oxidative stress and treat lesions. Argan-liposomes were the smallest vesicles (~113 nm); the addition of sodium hyaluronate led to an increase in vesicle size (~143 nm) but it significantly improved vesicle stability during storage. In vitro studies confirmed the free radical scavenging activity of formulations, irrespective of their composition. Moreover, rheological investigation confirmed the higher viscosity of argan-hyalurosomes, which avoid formulation leakage after application. In vitro studies performed by using the most representative cells of the skin (i.e., keratinocytes and fibroblasts) underlined the ability of vesicles, especially argan-liposomes and argan-hyalurosomes, to counteract oxidative stress induced in these cells by using hydrogen peroxide and to improve the proliferation and migration of cells ensuring the more rapid and even complete closure of the wound (scratch assay).

Thymoquinone, extract from Nigella sativa seeds, protects human skin keratinocytes against UVA-irradiated oxidative stress, inflammation and mitochondrial dysfunction

Ultraviolet A (UVA) irradiation caused skin keratinocytes to accumulate reactive oxygen species (ROS) leading to the skin injury. Thymoquinone (TQ) was identified as the prominent bioactive ingredient in Nigella sativa seeds which was applied in therapying various human diseases. This study aimed to illustrate the role and mechanism of TQ in UVA-induced skin injury. We pre-treated HaCaT cells with TQ and irradiated them by UVA. MTT and Elisa assays were used to evaluate cell viability and apoptosis, as well as cytokine levels. To detect the related parameters of oxidative stress and mitochondrial function, colorimetry, spectrophotometry, bioluminescence, and dual-luciferase reporter methods were used. RT-qPCR and western blotting were performed for expressions of related mRNAs and proteins. TQ significantly improved the UVA-induced cytotoxicity on HaCaT cells. TQ treatment alleviated the oxidative stress and inflammation in UVA-irradiated keratinocytes. Besides, UVA irradiation promoted mitochondrial dysregulation in HaCaT cells leading to cell apoptosis, which could be reversed by TQ treatment. More importantly, NrF2/ARE pathway was activated in TQ-treated cells, while COX-2 was depressed, and inhibiting the pathway or activating COX-2 blocked the therapeutic effect of TQ on UVA-induced skin cell injury. Our study suggested that TQ treatment attenuated the UVA-induced oxidative and inflammatory responses, as well as mitochondrial apoptosis in keratinocytes by COX-2 inhibition via activating NrF2/ARE pathway. This might be a novel sight for preventing the solar radiation damage to the skin.

In vivoorganized neovascularization induced by 3D bioprinted endothelial-derived extracellular vesicles

Extracellular vesicles (EVs) have become a key tool in the biotechnological landscape due to their well-documented ability to mediate intercellular communication. This feature has been explored and is under constant investigation by researchers, who have demonstrated the important role of EVs in several research fields ranging from oncology to immunology and diagnostics to regenerative medicine. Unfortunately, there are still some limitations to overcome before clinical application, including the inability to confine the EVs to strategically defined sites of interest to avoid side effects. In this study, for the first time, EV application is supported by 3D bioprinting technology to develop a new strategy for applying the angiogenic cargo of human umbilical vein endothelial cell-derived EVs in regenerative medicine. EVs, derived from human endothelial cells and grown under different stressed conditions, were collected and used as bioadditives for the formulation of advanced bioinks. Afterin vivosubcutaneous implantation, we demonstrated that the bioprinted 3D structures, loaded with EVs, supported the formation of a new functional vasculaturein situ, consisting of blood-perfused microvessels recapitulating the printed pattern. The results obtained in this study favour the development of new therapeutic approaches for critical clinical conditions, such as the need for prompt revascularization of ischaemic tissues, which represent the fundamental substrate for advanced regenerative medicine applications.

Lipid nanovesicles for biomedical applications: 'What is in a name'?

Vesicles, generally defined as self-assembled structures formed by single or multiple concentric bilayers that surround an aqueous core, have been widely used for biomedical applications. They can either occur naturally (e.g. exosomes) or be produced artificially and range from the micrometric scale to the nanoscale. One the most well-known vesicle is the liposome, largely employed as a drug delivery nanocarrier. Liposomes have been modified along the years to improve physicochemical and biological features, resulting in long-circulating, ligand-targeted and stimuli-responsive liposomes, among others. In this process, new nomenclatures were reported in an extensive literature. In many instances, the new names suggest the emergence of a new nanocarrier, which have caused confusion as to whether the vesicles are indeed new entities or could simply be considered modified liposomes. Herein, we discussed the extensive nomenclature of vesicles based on the suffix "some" that are employed for drug delivery and composed of various types and proportions of lipids and others amphiphilic compounds. New names have most often been selected based on changes of vesicle lipid composition, but the payload, structural complexity (e.g. multicompartment) and new/improved proprieties (e.g. elasticity) have also inspired new vesicle names. Based on this discussion, we suggested a rational classification for vesicles.

HPLC method development/validation and skin diffusion study of caffeine, methyl paraben and butyl paraben as skin-diffusing model drugs

The focus of this research was to develop and validate a suitable HPLC method, which allows simultaneous determination of three proposed skin model penetrants to investigate the percutaneous diffusion behavior of their combination: caffeine, methyl paraben and butyl paraben. These penetrants were selected because they represent a wide range of lipophilicities. This model highlights the effect of combining penetrants of different molecular properties on their diffusion behavior through skin. The proposed method employed a gradient system that was systematically optimized for separation and quantification of the penetrants. The effect of the stationary phase (C18, C4 and cyano (CN)) was assessed with CN proven to be superior in terms of peak shape, retentivity and dynamic linear range. Significant differences in retention time, peak broadening, and quantifiability between different stationary phases could be demonstrated. The method was validated as per ICH guidelines Q2 (R1) with a satisfactory outcome. The method was successfully applied for real diffusion experiments, and revealed notable differences between the individual penetrants and their ternary mixture on transdermal permeation. The method could potentially be extended to determine these analytes in other related skin permeation investigations.

Development of novel polyglycerol fatty acid ester-based nanoparticles for the dermal delivery of tocopherol acetate

The aim of this study was to develop and evaluate novel polyglycerol fatty acid ester (PGFE)-based nanoparticles (NPs) for the dermal delivery of tocopherol acetate (TA). TA-loaded PGFE-based NPs (PGFE-NPs) were prepared by mixing PGFE, soya phosphatidylcholine, dimyristoylphosphatidylglycerol, and TA with film using the film rehydration and extrusion method. The prepared formulations were analyzed by dynamic light scattering, small-angle X-ray diffraction and polarization microscopy. An in vitro skin accumulation test was performed with TA under occlusive and non-occlusive applications, using Yucatan micropig skin. The size range of the TA-loaded liposome and PGFE-NPs was 107-128 nm, and they were encapsulated in 1.6-2.3 mg/mL TA. All PGFE-NP formulations were negatively charged and stable for 2 weeks. Under occlusive applications, all formulations induced small amounts of TA accumulation in the epidermis but not in the dermis. However, under non-occlusive applications, some of PGFE-NP formulations enhanced TA accumulation in the epidermis. Furthermore, only the polyglycerol 4-laurate (PG4L)-based formulation induced dermal TA accumulation with the change in the formulation from a vesicular to bilayer stacked structure following water evaporation under non-occlusive applications. These results indicated that the novel TA-loaded PG4L formulation enabled the dermal delivery of TA in non-occlusive applications.

Extraction, Characterization and Incorporation of Hypericum scruglii Extract in Ad Hoc Formulated Phospholipid Vesicles Designed for the Treatment of Skin Diseases Connected with Oxidative Stress

An extract of Hypericum scruglii, an endangered endemic plant of Sardinia (Italy), was prepared and characterized. It was loaded in special phospholipid vesicles, glycerosomes, which were modified by adding maltodextrin (glucidex) and a polymer (gelatin or hyaluronan). The corresponding liposomes were also prepared and used as reference. The vesicles disclosed suitable physicochemical features for skin delivery. Indeed, their mean diameter ranged from 120 to 160 nm, they were homogeneously dispersed (polydispersity index ≤ 0.30), and their zeta potential was highly negative (~−45 mV). The vesicle dispersions maintained unchanged characteristics during 60 days of storage, were highly biocompatible, and were able to protect keratinocytes against damages due to oxidative stress induced by treating them with hydrogen peroxide. Vesicles were also capable of promoting cell proliferation and migration in vitro by means of a scratch wound assay. The results confirmed the fruitful delivery of the extract of H. scruglii in glycerosomes modified with glucidex and gelatin and their promising ability for skin protection and treatment.

Polyoliposomes: novel polyol-modified lipidic nanovesicles for dermal and transdermal delivery of drugs

Various lipid nanovesicular systems have been developed with the aim to enhance the delivery of drugs via transdermal route. However, their clinical applications are often limited due to the barrier nature of skin and lack of flexibility. Herein, we have modified the conventional nanoliposomes (CLs) prepared by a thin-film hydration method by the addition of a polyol (glycerol) to form novel lipid nanovesicular structures termed 'POLYOLIPOSOMES' (PLs). They were further named as PL-B (before film formation) and PL-A (after film formation), depending on the stage of glycerol addition during production. Optimized CLs, PL-B and PL-A showed spherical nanovesicles and hydrodynamic diameter of 181.3 ± 4.11 nm, 114.2 ± 7.21 nm and 170.2 ± 6.51 nm, respectively. PLs showed significantly higher % entrapment efficiency and deformability index in comparison to CLs, indicating their higher flexibility. Furthermore, DSC and attenuated total relection (ATR)-Fourier transform infrared (FTIR) studies revealed the intercalation of glycerol into the lipid bilayer of PLs and interaction between nanovesicles and skin. Moreover, ex vivo and in vivo skin permeation studies confirmed the enhanced drug delivery of PLs via the transdermal route. Taken together, these results illustrate the potential of PLs as a novel lipid nanovesicular system for drug delivery via the transdermal route for both systematic (PL-B) as well as cutaneous diseases (PL-A).

Co-loading of finasteride and baicalin in phospholipid vesicles tailored for the treatment of hair disorders

Hair loss affects a large number of people worldwide and it has a negative impact on the quality of life. Despite the availability of different drugs for the treatment of hair disorders, therapeutic options are still limited and scarcely effective. An innovative strategy to improve the efficacy of alopecia treatment is presented in this work. Finasteride, the only oral synthetic drug approved by Unites States Federal Drug Administration, was loaded in phospholipid vesicles. In addition, baicalin was co-loaded as an adjuvant. Their effect on hair growth was evaluated in vitro and in vivo. Liposomes, hyalurosomes, glycerosomes and glycerol-hyalurosomes were manufactured by using a simple method that avoids the use of organic solvents. All the vesicles were small in size (∼100 nm), homogeneously dispersed (polydispersity index ≤0.27) and negatively charged (∼-16 mV). The formulations were able to stimulate the proliferation of human dermal papilla cells, which are widely used in hair physiology studies. The analysis of hair growth and hair follicles of C57BL/6 mice, treated with the formulations for 21 days, underlined the ability of the vesicles to improve hair growth by the simultaneous follicular delivery of finasteride and baicalin. Therefore, the developed nanosystems can represent a promising tool to ensure the efficacy of the local treatment of hair loss.

Liposomes Entrapped in Biopolymer Hydrogels Can Spontaneously Release into the External Solution

Hydrogels of biopolymers such as agar and gelatin are widely used in many applications, and in many cases, the gels are loaded with nanoparticles. The polymer chains in these gels are cross-linked by physical bonds into three-dimensional networks, with the mesh size of these networks typically being 10-100 nm. One class of "soft" nanoparticles are liposomes, which have an aqueous core surrounded by a lipid bilayer. Solutes encapsulated in the liposomal core can be delivered externally over time. In this paper, we create liposomes with diameters ∼150 nm from an unsaturated phospholipid (lecithin) and embed them in agar gels (the aqueous phase also contains 0-50% of glycerol, which is an active ingredient in cosmetic products). Upon placing this gel in quiescent water, we find that the liposomes release out of the gel into the water over a period of 1-3 days, even though the gel remains intact. This is a surprising result that runs contrary to our expectation that the liposomes would simply remain immobilized in the gel. We show that the release rate of liposomes can be tuned by several variables: for example, the release rate increases as the agar concentration is lowered and the rate increases steadily with temperature. In addition to agar, release of liposomes also occurs out of other physical gels including those of agarose and gelatin. However, liposomes made from a saturated phospholipid do not release out of any gels. We discuss a possible mechanism for liposomal release, which involves intact liposomes deforming and squeezing through transient large pores that arise in physical networks such as agar. Our findings have relevance to transdermal delivery: they suggest the possibility of systematically delivering liposomes loaded with actives out of an intact matrix.

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.

Investigating the potential of utilizing glycerosomes as a novel vesicular platform for enhancing intranasal delivery of lacidipine

Lacidipine is a potent dihydropyridine calcium channel blocker used for management of hypertension and atherosclerosis. The drug has low and fluctuating oral bioavailability owing to its extensive hepatic first-pass metabolism and reduced water solubility. Accordingly, this work aimed at overcoming the aforementioned challenges through the formulation of intranasal nano-sized lacidipine glycerosomes. Box-Behnken was successfully employed for the formulation and in vitro optimization of the glycerosomes. Statistical analysis revealed that cholesterol concentration exhibited a significant effect on the vesicle size, while Phospholipon® 90G and glycerol concentrations exhibited significant effects on both entrapment efficiency and deformability index. The optimized formulation showed spherical shape, good deformability, vesicular size of 220.25 nm, entrapment efficiency of 61.97%, and enhanced ex vivo permeation by 3.65 fold compared to lacidipine suspension. Confocal laser scattering microscope revealed higher penetration depth via nasal mucosa for rhodamine labelled glycerosomes (up to 60 µm) in comparison to rhoadamine dye solution (26 µm). In addition, the optimized lacidipine glycerosomes caused significant reduction in methylprednisolone acetate-induced hypertension in rats for up to 24 h in comparison to oral drug suspension. Histopathological assessment showed intact nasal mucosal epithelial lining with no signs of inflammation or necrosis confirming the safety and tolerability of the proposed glycerosomes. The declared results highlights the potential of utilizing the proposed glycerosomes as safe and effective platform for intranasal delivery of lacidipine.

Preparation and optimization of fisetin loaded glycerol based soft nanovesicles by Box-Behnken design

The present study focused on the development and optimization of glycerosomes for dermal delivery of fisetin. The fisetin loaded glycerosomes formulation was optimized by Box-Behnken design. The independent variables were the lipoid S 100, glycerol, and sonication time, whereas the dependent variables were the vesicles size, entrapment efficiency, and flux. The mechanism of skin penetration of fisetin loaded glycerosomes formulation was determined by the DSC and FTIR studies. Confocal scanning microscopy was used to detect the penetration ability of glycerosomes. The optimized fisetin loaded glycerosomes formulation was converted into a Carbopol® gel matrix, and the latter was analyzed for various parameters. The optimized formulation of glycerosomes presented vesicles size, entrapment efficiency and flux of 138.8 ± 4.09 nm, 86.41 ± 2.95% and 5.04 ± 0.17 µg/cm²/h, respectively. The transmission electron microscopy of optimized fisetin loaded formulation revealed the spherical and sealed structure of glycerosomes vesicles. The confocal study confirmed that the Rhodamine B incorporated glycerosomes penetrated up to deeper layers of skin. The DSC and FTIR studies revealed that the hydration of skin layers and skin lipid fluidization could be the penetration mechanism of fisetin glycerosomes formulation. The optimized fisetin loaded glycerosomes gel formulation presented a flux of 4.24 ± 0.14 μg/cm²/h, and exhibited zero-order release kinetics. The texture analysis of fisetin glycerosomes gel displayed a sufficient hardness, consistency, cohesiveness, and index of viscosity. It was concluded that the prepared fisetin loaded glycerosomes gel was suitable for the dermal application.

Molecular Effects of Glycerol on Lipid Monolayers at the Gas-Liquid Interface: Impact on Microbubble Physical and Mechanical Properties

The production and stability of microbubbles (MBs) is enhanced by increasing the viscosity of both the formation and storage solution, respectively. Glycerol is a good candidate for biomedical applications of MBs, since it is biocompatible, although the exact molecular mechanisms of its action is not fully understood. Here, we investigate the influence glycerol has on lipid-shelled MB properties, using a range of techniques. Population lifetime and single bubble stability were studied using optical microscopy. Bubble stiffness measured by AFM compression is compared with lipid monolayer behavior in a Langmuir-Blodgett trough. We deduce that increasing glycerol concentrations enhances stability of MB populations through a 3-fold mechanism. First, binding of glycerol to lipid headgroups in the interfacial monolayer up to 10% glycerol increases MB stiffness but has limited impact on shell resistance to gas permeation and corresponding MB lifetime. Second, increased solution viscosity above 10% glycerol slows down the kinetics of gas transfer, markedly increasing MB stability. Third, above 10%, glycerol induces water structuring around the lipid monolayer, forming a glassy layer which also increases MB stiffness and resistance to gas loss. At 30% glycerol, the glassy layer is ablated, lowering the MB stiffness, but MB stability is further augmented. Although the molecular interactions of glycerol with the lipid monolayer modulate the MB lipid shell properties, MB lifetime continually increases from 0 to 30% glycerol, indicating that its viscosity is the dominant effect on MB solution stability. This three-fold action and biocompatibility makes glycerol ideal for therapeutic MB formation and storage and gives new insight into the action of glycerol on lipid monolayers at the gas-liquid interface.

Optimization of Innovative Three-Dimensionally-Structured Hybrid Vesicles to Improve the Cutaneous Delivery of Clotrimazole for the Treatment of Topical Candidiasis

New three-dimensionally-structured hybrid phospholipid vesicles, able to load clotrimazole in a high amount (10 mg/mL), were obtained for the first time in this work by significantly reducing the amount of water (≤10%), which was replaced with a mixture of glycerol and ethanol (≈90%). A pre-formulation study was carried out to evaluate the effect of both the composition of the hydrating medium and the concentration of the phospholipid on the physico-chemical properties of hybrid vesicles. Four different three-dimensionally-structured hybrid vesicles were selected as ideal systems for the topical application of clotrimazole. An extensive physico-chemical characterization performed using transmission electron microscopy (TEM), cryogenic transmission electron microscopy (cryo-TEM), ³¹P-NMR, and small-angle X-ray scattering (SAXS) displayed the formation of small, multi-, and unilamellar vesicles very close to each other, and was capable of forming a three-dimensional network, which stabilized the dispersion. Additionally, the dilution of the dispersion with water reduced the interactions between vesicles, leading to the formation of single unilamellar vesicles. The evaluation of the in vitro percutaneous delivery of clotrimazole showed an improved drug deposition in the skin strata provided by the three-dimensionally-structured vesicles with respect to the commercial cream (Canesten^®) used as a reference. Hybrid vesicles were highly biocompatible and showed a significant antifungal activity in vitro, greater than the commercial cream Canesten^®. The antimycotic efficacy of formulations was confirmed by the reduced proliferation of the yeast cells at the site of infection in vivo. In light of these results, clotrimazole-loaded, three-dimensionally-structured hybrid vesicles appear to be one of the most innovative and promising formulations for the treatment of candidiasis infections.

Curcumin entrapped hyaluronan containing niosomes: preparation, characterisation and in vitro/in vivo evaluation

Curcumin, a natural polyphenolic compound, has numerous pharmacological activities; while it faces several bioavailability problems, due to its poor solubility and stability. So, many nanostructures have been designed to overcome these drawbacks. The aim of this study was to prepare a polymeric niosomal structure by incorporating hyaluronan to improve curcumin efficiencies. Hyaluronan containing niosomes were prepared by thin film hydration medium with slight modifications. In the formulation of hyaluronan containing niosomes size and zeta potential studies, Atomic Force Microscopy (AFM), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC), X-Ray Diffraction (XRD), in-vitro release test, DPPH antioxidant assay and in-vivo anti-inflammatory test were investigated. The results showed that hyaluronan containing niosomes were 249.83 ± 6.38 nm and the entrapment of curcumin was 98.28 ± 0.278% (w/w). In addition, the shape of the hyaluronan containing niosomes was spherical. 500 µl of the prepared formulation with 4.002 × 10^-7 moles of curcumin showed 100% antioxidant effect. Moreover, the anti-inflammatory effect of the hyaluronan containing niosomes was higher than the anti-inflammatory effect of the simple suspension of curcumin.

DOC-LS, a new liposome for dermal delivery, and its endocytosis by HaCaT and CCC-ESF-1 cells

The main objective of this work was to investigate the uptake channels of skin cells through which coumarin 6, transported by deoxycholate-mediated liposomes (DOC-LS), was internalised; this was also compared against the action of conventional LS. Coumarin 6-loaded DOC-LS and LS were characterised for size distribution, zeta potential, and shape, and analysed in vitro in human epidermal immortal keratinocyte (HaCaT) (epidermal) and human embryonic skin fibroblast (CCC-ESF-1) (dermal) cell lines. Various endocytosis inhibitors were incubated with cells treated with the nanocarriers. Flow cytometry results indicated that HaCaT and CCC-ESF-1 cells internalise the tested preparations through pinocytotic vesicles, macropinocytosis, clathrin-mediated endocytic pathways, and via lysosomes, which consume a considerable amount of energy. The endocytosis pathways of DOC-LS and LS showed no difference. This study provides a basis for the application of LS being combined with a microneedle system for efficient intracellular drug delivery, targeting cutaneous histocyte disorders.

Caffeine delivery in porcine skin: a confocal Raman study

Confocal Raman microscopy is a novel optical method for studies of pro-drug and drug delivery. This method is a promising technique that enables non-destructive measurement of the permeation profile through skin layers. Peaks of compounds are usually normalised to skin peaks (amino-acid and amide I) for semi-quantitative evaluation. The present study seeks to optimise a methodology for complete quantitative measurement of the amount of an active compound at different depths. Caffeine was used as a tracer to evaluate compound's skin penetration using confocal Raman microscopy. A semi-quantitative depth profile of caffeine was obtained with normalisation of the Raman intensities. These ratios of Raman intensities were correlated with the caffeine concentration using an external calibration curve. The calibration curve was carried out with porcine skin incubated in different concentrations of caffeine; afterwards, each skin sample was analysed by confocal Raman microscopy and HPLC to determine the relation between the Raman signal intensity and the caffeine concentration per skin mass and to create a depth profile. These correlation curves allow the full quantification of the caffeine in skin from Raman intensity ratios at different depths.

Functional G-Protein-Coupled Receptor (GPCR) Synthesis: The Pharmacological Analysis of Human Histamine H1 Receptor (HRH1) Synthesized by a Wheat Germ Cell-Free Protein Synthesis System Combined with Asolectin Glycerosomes

G-protein-coupled receptors (GPCRs) are membrane proteins distributed on the cell surface, and they may be potential drug targets. However, synthesizing GPCRs in vitro can be challenging. Recently, some cell-free protein synthesis systems have been shown to produce a large amount of membrane protein combined with chemical chaperones that include liposomes and glycerol. Liposomes containing high concentrations of glycerol are known as glycerosomes, which are used in new drug delivery systems. Glycerosomes have greater morphological stability than liposomes. Proteoglycerosomes are defined as glycerosomes that contain membrane proteins. Human histamine H₁ receptor (HRH1) is one of the most studied GPCRs. In this study, we synthesized wild-type HRH1 (WT-HRH1) proteoglycerosomes and D107A-HRH1, (in which Asp107 was replaced by Ala) in a wheat germ cell-free protein synthesis system combined with asolectin glycerosomes. The mutant HRH1 has been reported to have low affinity for the H₁ antagonist. In this study, the amount of synthesized WT-HRH1 in one synthesis reaction was 434 ± 66.6 μg (7.75 ± 1.19 × 10³pmol). The specific binding of [³H]pyrilamine to the WT-HRH1 proteoglycerosomes became saturated as the concentration of the radioligand increased. The dissociation constant (Kd) and maximum density (Bmax) of the synthesized WT-HRH1 were 9.76 ± 1.25 nM and 21.4 ± 0.936 pmol/mg protein, respectively. However, specific binding to D107A-HRH1 was reduced compared with WT-HRH1 and the binding did not become saturated. The findings of this study highlight that HRH1 synthesized using a wheat germ cell-free protein synthesis system combined with glycerosomes has the ability to bind to H₁ antagonists.

Technical challenges of working with extracellular vesicles

Extracellular Vesicles (EVs) are gaining interest as central players in liquid biopsies, with potential applications in diagnosis, prognosis and therapeutic guidance in most pathological conditions. These nanosized particles transmit signals determined by their protein, lipid, nucleic acid and sugar content, and the unique molecular pattern of EVs dictates the type of signal to be transmitted to recipient cells. However, their small sizes and the limited quantities that can usually be obtained from patient-derived samples pose a number of challenges to their isolation, study and characterization. These challenges and some possible options to overcome them are discussed in this review.

Glycerosomes: Investigation of role of 1,2-dimyristoyl-sn-glycero-3-phosphatidycholine (DMPC) on the assembling and skin delivery performances

Glycerosomes were formulated using 1,2-dimyristoyl-sn-glycero-3-phosphatidycholine (DMPC), diclofenac sodium salt and 10, 20 or 30% glycerol in the water phase, while corresponding liposomes were prepared with the same amount of DMPC and diclofenac, without glycerol. The aim of the present work was to evaluate the effect of the used phospholipid on vesicle features and ability to favour diclofenac skin deposition by comparing these results with those found in previous works performed using hydrogenated soy phosphatidylcholine (P90H) and dipalmitoylphosphatidylcholine (DPPC). Liposomes and glycerosomes were multilamellar, liposomes being smaller (72±6nm). Interactions among glycerol, phospholipids and drug led to the formation of a non-rigid bilayer structure and a variation of the main transition temperature, which shifted to lower temperature. The addition of glycerol led to the formation of more viscous systems (from ∼2.5mPa/s for basic liposomes to ∼5mPa/s for glycerosomes), which improved spread ability of the formulations on the skin.Results obtained in vitro were promising using glycerosomes, irrespective of the amount of glycerol used: the amount of drug, which accumulated into and permeated through the different skin strata, was high and comparable with that obtained using P90H, suggesting that glycerosomes may represent an efficient carrier for both local effect or systemic absorption.