Ethosomes for skin delivery of ropivacaine: preparation, characterization and ex vivo penetration properties

Design, statistical optimization, in vitro and biological characterization of Eudragit L100-gelatin based buccoadhesive bilayer patch for managing oral mucositis

This study deals with the development of a bilayer biodegradable mucoadhesive patch using the solvent casting approach, incorporating a ropivacaine (RC)-loaded gelatin layer and an itopride (IP)-loaded eudragit L100 layer for managing oral mucositis, nausea, vomiting, and gastrointestinal disorders. The patch was evaluated for several parameters including patch thickness, weight variation, folding endurance, moisture content, surface pH, drug content, in-vitro drug release, stability, swelling ratio, and water absorption capacity. The layers were optimized using a Box-Behnken Design, while studying the effect of concentration of gelatin or eudragit, plasticizer, drying temperature and drying time on dependent variables such as film weight, film thickness, swelling capacity, and disintegration time. The RC-gelatin layer exhibited weights ranging from 200 to 2120 mg, swelling of 35-85 %, and disintegration times between 8 and 22 h, with a drug content of 94-102 %. The eudragit layer demonstrated controlled drug release (60 % over 8 h). FTIR, TGA, DSC and XRD confirmed compatibility of ingredients, while SEM demonstrated homogeneous drug distribution. Negative zeta potential (-16.8 mV) confirmed the stability of patch. Tail flick tests in rats confirmed local anesthetic action, and strong mucoadhesive strength was observed in rabbits' buccal mucosa. Cytotoxicity studies exhibited enhanced cell survival, while histopathological analysis demonstrated no inflammatory or harmful effects, confirming the safety of the patch.

Karanjin-loaded soya lecithin-based ethosomal nanogel for the therapeutic intervention of psoriasis: formulation development, factorial design based-optimization,in vitroandin vivoassessment

This study aimed to develop and optimize karanjin-loaded ethosomal nanogel formulation and evaluate its efficacy in alleviating symptoms of psoriasis in an animal model induced by imiquimod. These karanjin-loaded ethosomal nanogel, were formulated to enhance drug penetration into the skin and its epidermal retention. Karanjin was taken to formulate ethosomes due to its potential ani-psoriatic activity. Ethosomes were formulated using the cold method using 32full factorial designs to optimize the formulation components. 9 batches were prepared using two independent variablesX1: concentration of ethanol andX2: concentration of phospholipid whereas vesicle size (Y1) and percentage entrapment efficiency (Y2) were selected as dependent variables. All the dependent variables were found to be statistically significant. The optimized ethosomal suspension (B3) exhibited a vesicle size of 334 ± 2.89 nm with an entrapment efficiency of 94.88 ± 1.24% and showed good stability. The morphology of vesicles appeared spherical with smooth surfaces through transmission electron microscopy analysis. X-ray diffraction analysis confirmed that the drug existed in an amorphous state within the ethosomal formulation. The optimized ethosome was incorporated into carbopol 934 to develop nanogel for easy application on the skin. The nanogel underwent characterization for various parameters including spreadability, viscosity, pH, extrudability, and percentage drug content. The ethosomal formulation remarkably enhanced the skin permeation of karanjin and increased epidermal retention of the drug in psoriatic skin compared to marketed preparation and pure drug. A skin retention study showed that ethosomal nanogel formulation has 48.33% epidermal retention in 6 h.In vivo,the anti-psoriatic activity of karanjin ethosomal nanogel demonstrated significant improvement in psoriasis, indicated by a gradual decrease in skin thickness and scaling as reflected in the Psoriasis Severity Index grading. Therefore, the prepared ethosomal nanogel is a potential vehicle for improved topical delivery of karanjin for better treatment of psoriasis.

Characterization Methods for Nanoparticle-Skin Interactions: An Overview

Research progresses have led to the development of different kinds of nanoplatforms to deliver drugs through different biological membranes. Particularly, nanocarriers represent a precious means to treat skin pathologies, due to their capability to solubilize lipophilic and hydrophilic drugs, to control their release, and to promote their permeation through the stratum corneum barrier. A crucial point in the development of nano-delivery systems relies on their characterization, as well as in the assessment of their interaction with tissues, in order to predict their fate under in vivo administration. The size of nanoparticles, their shape, and the type of matrix can influence their biodistribution inside the skin strata and their cellular uptake. In this respect, an overview of some characterization methods employed to investigate nanoparticles intended for topical administration is presented here, namely dynamic light scattering, zeta potential, scanning and transmission electron microscopy, X-ray diffraction, atomic force microscopy, Fourier transform infrared and Raman spectroscopy. In addition, the main fluorescence methods employed to detect the in vitro nanoparticles interaction with skin cell lines, such as fluorescence-activated cell sorting or confocal imaging, are described, considering different examples of applications. Finally, recent studies on the techniques employed to determine the nanoparticle presence in the skin by ex vivo and in vivo models are reported.

Delivery Strategies for Colchicine as a Critical Dose Drug: Reducing Toxicity and Enhancing Efficacy

Colchicine (COL), a widely used natural drug, has potent anti-inflammatory effects; however, as a narrow therapeutic index drug, its clinical application is limited by its serious gastrointestinal adverse effects, and only oral formulations are currently marketed worldwide. Recent studies have shown that transdermal, injection, and oral drug delivery are the three main delivery strategies for COL. This article elaborates on the research progress of different delivery strategies in terms of toxicity reduction and efficacy enhancement, depicting that the transdermal drug delivery route can avoid the first-pass effect and the traumatic pain associated with the oral and injection routes, respectively. Therefore, such a dosage form holds a significant promise that requires the development of further research to investigate effective COL delivery formulations. In addition, the permeation-promoting technologies utilized for transdermal drug delivery systems are briefly discussed. This article is expected to provide scientific ideas and theoretical guidance for future research and the exploration of COL delivery strategies.

Combination anesthetic therapy: co-delivery of ropivacaine and meloxicam using transcriptional transactivator peptide modified nanostructured lipid carriers in vitro and in vivo

Combination therapy combining two drugs in one modified drug delivery system is used to achieve synergistic analgesic effect, and bring effective control of pain management, especially postoperative pain management. In the present study, a combination of drug delivery technologies was utilized. Transcriptional transactivator (TAT) peptide modified, transdermal nanocarriers were designed to co-deliver ropivacaine (RVC) and meloxicam (MLX) and anticipated to achieve longer analgesic effect and lower side effect. TAT modified nanostructured lipid carriers (TAT-NLCs) were used to co-deliver RVC and MLX. RVC and MLX co-loaded TAT-NLCs (TAT-NLCs-RVC/MLX) were evaluated through in vitro skin permeation and in vivo treatment studies. NLCs-RVC/MLX showed uniform and spherical morphology, with a size of 133.4 ± 4.6 nm and a zeta potential of 20.6 ± 1.8 mV. The results illustrated the anesthetic pain relief ability of the present constructed system was significantly improved by the TAT modification through the enhanced skin permeation efficiency and the co-delivery of MLX along with RVC that improved pain management by reducing inflammation at the injured area. This study provides an efficient and facile method for preparing TAT-NLCs-RVC/MLX as a promising system to achieve synergistic analgesic effect.

Fabrication of Ropivacaine/Dexamethasone-Eluting Poly(D, L-lactide-co-glycolide) Microparticles via Electrospraying Technique for Postoperational Pain Control

Microencapsulation plays an important role in biomedical technology owing to its particular and attractive characteristics. In this work, we developed ropivacaine and dexamethasone loaded poly(D, L-lactide-co-glycolide) (PLGA) microparticles via electrospraying technique and investigated the release behavior of electrosprayed microparticles. The particle morphology of sprayed particles was assessed using scanning electron microscopy (SEM). The in vitro drug release kinetics were evaluated employing an elution method, and the in vivo pharmaceutical release as well as its efficacy on pain relief were tested using an animal activity model. The microscopic observation suggested that sprayed microparticles exhibit a size distribution of 5-6 µm. Fourier-transform infrared spectrometry and differential scanning calorimetry demonstrated the successful incorporation of pharmaceuticals in the PLGA particulates. The drugs-loaded particles discharged sustainably high concentrations of ropivacaine and dexamethasone at the target region in vivo for over two weeks, and the drug levels in the blood remained low. By adopting the electrospraying technique, we were able to prepare drug-embedded polymeric microparticles with effectiveness and with a sustainable capability for postoperative pain control.

The technology of transdermal delivery nanosystems: from design and development to preclinical studies

Transdermal administration has gained much attention due to the remarkable advantages such as patient compliance, drug escape from first-pass elimination, favorable pharmacokinetic profile and prolonged release properties. However, the major limitation of these systems is the limited skin penetration of the stratum corneum, the skin's most important barrier, which protects the body from the insertion of substances from the environment. Transdermal drug delivery systems are aiming to the disruption of the stratum corneum in order for the active pharmaceutical ingredients to enter successfully the circulation. Therefore, nanoparticles are holding a great promise because they can act as effective penetration enhancers due to their small size and other physicochemical properties that will be analyzed thoroughly in this report. Apart from the investigation of the physicochemical parameters, a comparison between the different types of nanoparticles will be performed. The complexity of skin anatomy and the unclear mechanisms of penetration should be taken into consideration to reach some realistic conclusions regarding the way that the described parameters affect the skin permeability. To the best of the authors knowledge, this is among the few reports on the literature describing the technology of transdermal delivery systems and how this technology affects the biological activity.

Characterization and Ex vivo Evaluation of Curcumin Nanoethosomes for Melanoma treatment

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

Anti-inflammatory ethosomal nanoformulation in combination with iontophoresis in chronic wound healing: An ex vivo study

Prescription of anti-inflammatory drugs may be considered as a promising strategy in chronic wound healing where the inflammatory disturbance has delayed the healing process. It seems that hydrocortisone 17-butyrate (HB17) would be promising in the form of a nano-formulation to enhance drug delivery efficacy. In the present study, transdermal delivery of nano-HB17 in combination with iontophoresis was investigated ex vivo. Ethosomal-HB17 was synthesised using lecithin, ethanol and cholesterol with a different ratio by hot method. The negative ethosomal-HB17 particle size was around 244 ± 4.3 nm with high stability of up to 30 days. Additionally, evaluated entrapment efficiency of HB17 in ethosomes by high performance liquid chromatography was 40.6 ± 2.21%. Moreover, the permeation speed and amount of H17B in complete-thickness rat skin in the presence and absence of iontophoresis showed that the penetration of free H17B and ethosomal-H17B formulations were zero and 7.98 μg/cm² in 120 min, respectively. Whereas in the case of applying iontophoresis, permeation amount obtained was zero and 19.69 μg/cm² in 30 min in free H17B and ethosomal-H17B formulations, respectively. It has been concluded that transdermal delivery of ethosomal-H17B is an effective strategy to enhance drug delivery and it will be improved when it is combined with iontophoresis.

Formulation and Evaluation of Resveratrol Loaded Cubosomal Nanoformulation for Topical Delivery

AIM

The aim of the study was to formulate, characterize, and evaluate the Resveratrol- loaded Cubosomes (RC) for topical application.

BACKGROUND

Resveratrol (RV) is a nutraceutical compound with exciting pharmacological potential in different diseases, including cancers. Many studies on resveratrol have been reported for anti- melanoma activity. Due to its low bioavailability, the therapeutic activities of resveratrol are strongly limited. Hence, an approach with nanotechnology has been made to increase its activity through transdermal drug delivery.

OBJECTIVE

To formulate, characterize, and evaluate the resveratrol-loaded cubosomes (RC). To evaluate Resveratrol-loaded Cubosomal Gel (RC-Gel) for its topical application.

METHODS

RC was formulated by homogenization technique and optimized using a 2-factor 3-level factorial design. Formulated RCs were characterized for particle size, zeta potential, and entrapment efficiency. Optimized RC was evaluated for in vitro release and stability study. Optimized RC was further formulated into cubosomal gel (RC-Gel) using carbopol and evaluated for drug permeation and deposition. Furthermore, developed RC-Gel was evaluated for its topical application using skin irritancy, toxicity, and in vivo local bioavailability studies.

RESULTS

The optimized RC indicated cubic-shaped structure with mean particle size, entrapment efficiency, and zeta potential were 113±2.36 nm, 85.07 ± 0.91%, and -27.40 ± 1.40 mV, respectively. In vitro drug release of optimized RC demonstrated biphasic drug release with the diffusion-controlled release of resveratrol (RV) (87.20 ± 3.91%). The RC-Gel demonstrated better drug permeation and deposition in mice skin layers. The composition of RC-Gel has been proved non-irritant to mice skin. In vivo local bioavailability study depicted the good potential of RC-Gel for skin localization.

CONCLUSION

The RC nanoformulation proposes a promising drug delivery system for melanoma treatment simply through topical application.

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

Background

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

Results

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

Conclusions

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

Supplementary Information

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

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

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

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

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

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

BACKGROUND

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Self-Assembled Lecithin/Chitosan Nanoparticles Based on Phospholipid Complex: A Feasible Strategy to Improve Entrapment Efficiency and Transdermal Delivery of Poorly Lipophilic Drug

PURPOSE

Lecithin/chitosan nanoparticles have shown great promise in the transdermal delivery of therapeutic agents. Baicalein, a natural bioactive flavonoid, possesses multiple biological activities against dermatosis. However, its topical application is limited due to its inherently poor hydrophilicity and lipophilicity. In this study, the baicalein-phospholipid complex was prepared to enhance the lipophilicity of baicalein and then lecithin/chitosan nanoparticles loaded with the baicalein-phospholipid complex were developed to improve the transdermal retention and permeability of baicalein.

METHODS

Lecithin/chitosan nanoparticles were prepared by the solvent-injection method and characterized in terms of particle size distribution, zeta potential, and morphology. The in vitro release, the ex vivo and in vivo permeation studies, and safety evaluation of lecithin/chitosan nanoparticles were performed to evaluate the effectiveness in enhancing transdermal retention and permeability of baicalein.

RESULTS

The lecithin/chitosan nanoparticles obtained by the self-assembled interaction of chitosan and lecithin not only efficiently encapsulated the drug with high entrapment efficiency (84.5%) but also provided sustained release of baicalein without initial burst release. Importantly, analysis of the permeation profile ex vivo and in vivo demonstrated that lecithin/chitosan nanoparticles prolonged the retention of baicalein in the skin and efficiently penetrated the barrier of stratum corneum without displaying skin irritation.

CONCLUSION

These results indicate the potential of drug-phospholipid complexes in enhancing the entrapment efficiency and self-assembled lecithin/chitosan nanoparticles based on phospholipid complexes in the design of a rational transdermal delivery platform to improve the efficiency of transdermal therapy by enhancing its percutaneous retention and penetration in the skin.

A brief overview on nano-sized materials used in the topical treatment of skin and soft tissue bacterial infections

Introduction: Skin and soft tissue infections are a significant clinical problem that can happen anywhere on the body. Bacteria are the most common cause of skin and soft tissue infections in humans. Despite the fact that there is a lot of antimicrobial agents and antibiotics for elucidating bacterial infections, the prevention and control of infectious diseases continue to be one of the greatest challenges for public health worldwide. At the present time, an alarming increase in multidrug resistance instantly requests to find suitable alternatives to current antibiotics. Therefore, drug resistance has been attempted to be resolved by the development of new classes of antimicrobial agents or targeted delivery systems for antibacterial drugs using nanotechnology.Area covered: The present review summarizes the emerging topical efforts to support the use of nano-sized materials as a new opportunity to combat today's skin infectious diseases.Expert opinion: Nano-sized materials can overcome the stratum corneum barrier and deliver drugs specifically to bacterial skin infections with trivial side effects. Depending on the physicochemical characteristics of nano-scaled materials, they can specifically be selected to target bacterial pathogens and also to get into the skin layers. These systems can overcome the antibiotic-resistance mechanisms and help us to the design of novel topical formulations that will make administration of antibacterial compounds safer, easier and more convenient.

Topical anesthetic analgesic therapy using the combination of ropivacaine and dexmedetomidine: hyaluronic acid modified long-acting nanostructured lipid carriers containing a skin penetration enhancer

Purpose

Hyaluronic acid-poly(ethylene glycol)-distearoyl phosphoethanolamine (HA-PEG-DSPE) modified and tocopheryl polyethylene glycol 1000 succinate (TPGS) contained nanostructured lipid carriers (NLCs) were prepared loading ropivacaine and dexmedetomidine to improve the topical anesthetic analgesic anesthesia efficiency.

Methods

NLCs were prepared by the solvent diffusion method. The average particle size, zeta potential, release behavior, and cytotoxicity of the NLCs were tested. Ex vivo skin permeation was studied using a Franz diffusion cell mounted with depilated rat skin. Local anesthesia antinociceptive efficiency was evaluated by rat tail flick latency study in vivo.

Results

NLCs have sizes of about 100 nm, with negative zeta potentials. All the NLCs formulations were found to be significantly less cytotoxic than free drugs at equivalent concentrations. The cumulative amount of drugs penetrated through rat skin from NLCs was 2.0–4.7 folds higher than that of the drugs solution. The in vivo anesthesia antinociception study displayed that NLCs showed stronger and longer anesthesia antinociceptive effect when compared with single drugs loaded NLCs and drugs solution even at a lower dosage of drugs.

Conclusion

The results demonstrated that the HA modified, TPGS contained, dual drugs loaded NLCs could perform a synergistic effect and may reduce the amount of drugs, which can lower the toxicity of the system and at the meanwhile, increase the anesthesia antinociceptive efficiency.

Factorial design based curcumin ethosomal nanocarriers for the skin cancer delivery: in vitro evaluation

Melanoma is the most deadly and life-threatening form of skin cancer with progressively higher rates of incidence worldwide. The objective of the present investigation is to develop and to statistically optimize and characterize curcumin (CUR) loaded ethosomes for treatment of melanoma. A two factor, three level (3²) factorial design approach was employed for the optimization of ethosomes. The prepared ethosomes were evaluated for size, zeta potential, entrapment efficiency, in vitro skin permeation and deposition ability. The optimized ethosomal formulation was evaluated for in vitro cytotoxicity and cellular uptake studies using A375 human melanoma cells. The optimized formulation has imperfect round shaped unilamellar structures with a mean vesicle size of 247 ± 5.25 nm and an entrapment efficiency of 92.24 ± 0.20%. The in vitro skin permeation studies proved the superiority of ethosomes over the traditional liposomes in terms of the amount of drug permeated and deposited in skin layers. Fluorescence microscopy showed the enhanced penetration of ethosomes into the deeper layers of the skin. In vitro cytotoxicity and cellular uptake studies revealed that curcumin ethosomes have significantly improved cytotoxicity and cellular uptake in A375 human melanoma cell lines. The colony formation assay results showed that curcumin ethosomes have a superior antiproliferative effect as they effectively inhibit the clonogenic ability of A375 cells. The flow cytometry results indicate that curcumin ethosomes induce cell death in A375 cells by apoptosis mechanism. The present study provides a strong rationale and motivation for further investigation of newly developed curcumin ethosomes as a potential therapeutic strategy for melanoma treatment.

Combined use of nanocarriers and physical methods for percutaneous penetration enhancement

Dermal and transdermal drug delivery (due to its non-invasiveness, avoidance of the first-pass metabolism, controlling the rate of drug input over a prolonged time, etc.) have gained significant acceptance. Several methods are employed to overcome the permeability barrier of the skin, improving drug penetration into/through skin. Among chemical penetration enhancement methods, nanocarriers have been extensively studied. When applied alone, nanocarriers mostly deliver drugs to skin and can be used to treat skin diseases. To achieve effective transdermal drug delivery, nanocarriers should be applied with physical methods, as they act synergistically in enhancing drug penetration. This review describes combined use of frequently used nanocarriers (liposomes, novel elastic vesicles, lipid-based and polymer-based nanoparticles and dendrimers) with the most efficient physical methods (microneedles, iontophoresis, ultrasound and electroporation) and demonstrates superiority of the combined use of nanocarriers and physical methods in drug penetration enhancement compared to their single use.

Current progress and challenges of nanoparticle-based therapeutics in pain management

Pain is a widespread and growing health problem worldwide that exerts a considerable social and economic impact on both patients and healthcare systems and, therefore, on society in general. Although current treatment modalities include a wide variety of pharmacological and non-pharmacological approaches, due to the complexity of pain and individual differences in clinical response these options are not always effective in mitigating and relieving pain. In addition, some pain drugs such as non-steroidal anti-inflammatory drugs (NSAIDs), local anesthetics and opioids show several unfavorable side effects. Therefore, current research advances in this medical field are based on the development of potential treatments to address many of the unmet needs and to overcome the existing limitations in pain management. Nanoparticle drug delivery systems present an exciting opportunity as alternative platforms to improve efficacy and safety of medications currently in use. Herein, we review a broad range of nanoparticle formulations (organic nanostructures and inorganic nanoparticles), which have been developed to encapsulate an array of painkillers, paying special attention to the key advantages that these systems offer, (compared to the use of the free drug), as well as to the more relevant results of preclinical studies in animal models. Additionally, we will briefly discuss the impact of some of these nanoformulations in clinical trials.

A novel local anesthetic system: transcriptional transactivator peptide-decorated nanocarriers for skin delivery of ropivacaine

Purpose

Barrier properties of the skin and physicochemical properties of drugs are the main factors for the delivery of local anesthetic molecules. The present work evaluates the anesthetic efficacy of drug-loaded nanocarrier (NC) systems for the delivery of local anesthetic drug, ropivacaine (RVC).

Methods

In this study, transcriptional transactivator peptide (TAT)-decorated RVC-loaded NCs (TAT-RVC/NCs) were successfully fabricated. Physicochemical properties of NCs were determined in terms of particle size, zeta potential, drug encapsulation efficiency, drug-loading capacity, stability, and in vitro drug release. The skin permeation of NCs was examined using a Franz diffusion cell mounted with depilated mouse skin in vitro, and in vivo anesthetic effect was evaluated in mice.

Results

The results showed that TAT-RVC/NCs have a mean diameter of 133.2 nm and high drug-loading capacity of 81.7%. From the in vitro skin permeation results, it was observed that transdermal flux of TAT-RVC/NCs was higher than that of RVC-loaded NCs (RVC/NCs) and RVC injection. The evaluation of in vivo anesthetic effect illustrated that TAT-RVC/NCs can enhance the transdermal delivery of RVC by reducing the pain threshold in mice.

Conclusion

These results indicate that TAT-decorated NCs systems are useful for overcoming the barrier function of the skin, decreasing the dosage of RVC and enhancing the anesthetic effect. Therefore, TAT-decorated NCs can be used as an effective transdermal delivery system for local anesthesia.

Recent Advances in Lipid-Based Vesicles and Particulate Carriers for Topical and Transdermal Application

In the recent decade, skin delivery (topical and transdermal) has gained an unprecedented popularity, especially due to increased incidences of chronic skin diseases, demand for targeted and patient compliant delivery, and interest in life cycle management strategies among pharmaceutical companies. Literature review of recent publications indicates that among various skin delivery systems, lipid-based delivery systems (vesicular carriers and lipid particulate systems) have been the most successful. Vesicular carriers consist of liposomes, ultradeformable liposomes, and ethosomes, while lipid particulate systems consist of lipospheres, solid lipid nanoparticles, and nanostructured lipid carriers. These systems can increase the skin drug transport by improving drug solubilization in the formulation, drug partitioning into the skin, and fluidizing skin lipids. Considering that lipid-based delivery systems are regarded as safe and efficient, they are proving to be an attractive delivery strategy for the pharmaceutical as well as cosmeceutical drug substances. However, development of these delivery systems requires comprehensive understanding of physicochemical characteristics of drug and delivery carriers, formulation and process variables, mechanism of skin delivery, recent technological advancements, specific limitations, and regulatory considerations. Therefore, this review article encompasses recent research advances addressing the aforementioned issues.