Development of triptolide-nanoemulsion gels for percutaneous administration: physicochemical, transport, pharmacokinetic and pharmacodynamic characteristics

Enhanced in vivo Stability and Antitumor Efficacy of PEGylated Liposomes of Paclitaxel Palmitate Prodrug

Purpose

The clinical use of paclitaxel (PTX) in cancer treatment is limited by its poor water solubility, significant toxicity, and adverse effects. This study aimed to propose a straightforward and efficient approach to enhance PTX loading and stability, thereby offering insights for targeted therapy against tumors.

Patients and Methods

We synthesized a paclitaxel palmitate (PTX-PA) prodrug by conjugating palmitic acid (PA) to PTX and encapsulating it into liposomal vehicles using a nano delivery system. Subsequently, we investigated the in vitro and in vivo performance as well as the underlying mechanisms of PTX-PA liposomes (PTX-PA-L).

Results

PTX had a remarkable antitumor effect in vivo and significantly decreased the myelosuppressive toxicity of PTX. Moreover, the introduction of PA increased the lipid solubility of PTX, forming a phospholipid bilayer as a membrane stabilizer, prolonging the circulation time of the drug and indirectly increasing the accumulation of liposomes at the tumor site. Our in vivo imaging experiments demonstrated that PTX-PA-L labeled with DiR has greater stability in vivo than blank liposomes and that PTX-PA-L can target drugs to the tumor site and efficiently release PTX to exert antitumor effects. In a mouse model, the concentration of PTX at the tumor site in the PTX-PA-L group was approximately twofold greater than that of Taxol. However, in a nude mouse model, the concentration of PTX at the tumor site in the PTX-PA-L group was only approximately 0.8-fold greater than that of Taxol. Furthermore, the originally observed favorable pharmacodynamics in normal mice were reversed following immunosuppression. This may be caused by differences in esterase distribution and immunity.

Conclusion

This prodrug technology combined with liposomes is a simple and effective therapeutic strategy with promising developmental prospects in tumor-targeted therapy owing to its ability to convert PTX into a long-circulating nano drug with low toxicity, high pharmacodynamics, and good stability in vivo.

Colistin-niclosamide-loaded nanoemulsions and nanoemulsion gels for effective therapy of colistin-resistant Salmonella infections

Colistin (COL) is regarded as a last-resort treatment for infections by multidrug-resistant (MDR) Gram-negative bacteria. The emergence of colistin-resistant Enterobacterales poses a significant global public health concern. Our study discovered that niclosamide (NIC) reverses COL resistance in Salmonella via a checkerboard assay. However, poor solubility and bioavailability of NIC pose challenges. In this study, we prepared a self-nanoemulsifying drug delivery system (SNEDDS) co-encapsulating NIC and COL. We characterized the physicochemical properties of the resulting colistin-niclosamide-loaded nanoemulsions (COL/NIC-NEs) and colistin-niclosamide-loaded nanoemulsion gels (COL/NIC-NEGs), assessing their antibacterial efficacy in vitro and in vivo. The COL/NIC-NEs exhibited a droplet size of 19.86 nm with a zeta potential of -1.25 mV. COL/NIC-NEs have excellent stability, significantly enhancing the solubility of NIC while also demonstrating a pronounced sustained-release effect. Antimicrobial assays revealed that the MIC of COL in COL/NIC-NEs was reduced by 16-128 times compared to free COL. Killing kinetics and scanning electron microscopy confirmed enhanced antibacterial activity. Antibacterial mechanism studies reveal that the COL/NIC-NEs and COL/NIC-NEGs could enhance the bactericidal activity by damaging cell membranes, disrupting proton motive force (PMF), inhibiting multidrug efflux pump, and promoting oxidative damage. The therapeutic efficacy of the COL/NIC-NEs and COL/NIC-NEGs is further demonstrated in mouse intraperitoneal infection models with COL-resistant Salmonella. To sum up, COL/NIC-NEs and COL/NIC-NEGs are a potentially effective strategies promising against COL-resistant Salmonella infections.

Active pharmaceutical ingredient-ionic liquids assisted follicular co-delivery of ferulic acid and finasteride for enhancing targeted anti-alopecia

Androgenetic alopecia (AGA) is the primary hair loss with impairing patients' quality of life. Finasteride (FIN) is an SRD5A2 inhibitor for AGA treatment, but oral FIN causes systemic adverse effects. Topical FIN delivery is anticipated to overcome this problem. Ferulic acid (FA) is a natural phenolic acid with vascular remodeling and anti-inflammatory effects. Herein, an active pharmaceutical ingredient ionic liquid (API IL) based on choline and FA (CF-IL) is for the first time constructed to load FIN for fabricating FIN CF-IL. CF-IL aims to act as carriers and cargos and enhance hair follicle (HF) co-delivery of FA and FIN for synergistic anti-alopecia. Thermal and spectroscopic analysis combined with quantum chemistry calculations and molecular dynamics confirm the formation of CF-IL. The CF-IL simultaneously increases the solubility of FA (∼648-fold) and FIN (∼686-fold), enhances the permeation and retention of FIN and FA through the follicular pathway, and promotes cellular uptake. FIN CFIL regulates the abnormal mRNA expressions in dihydrotestosterone-irritated hDPCs, and promotes hair regrowth in AGA mice in a combined manner with FIN and FA. These findings suggest that FA-based API IL is a promising approach for percutaneously co-delivering FA and FIN to HF, providing an enhanced targeting treatment for AGA.

Topical Formulations Based on Ursolic Acid-Loaded Nanoemulgel with Potential Application in Psoriasis Treatment

Psoriasis is a chronic disorder that causes a rash with itchy, scaly patches. It affects nearly 2-5% of the worldwide population and has a negative effect on patient quality of life. A variety of therapeutic approaches, e.g., glucocorticoid topical therapy, have shown limited efficacy with systemic adverse reactions. Therefore, novel therapeutic agents and physicochemical formulations are in constant need and should be obtained and tested in terms of effectiveness and minimization of side effects. For that reason, the aim of our study was to design and obtain various hybrid systems, nanoemulgel-macroemulsion and nanoemulgel-oleogel (bigel), as vehicles for ursolic acid (UA) and to verify their potential as topical formulations used in psoriasis treatment. Obtained topical formulations were characterized by conducting morphological, rheological, texture, and stability analysis. To determine the safety and effectiveness of the prepared ursolic acid carriers, in vitro studies on human keratinocyte cell-like HaCaT cells were performed with cytotoxicity analysis for individual components and each formulation. Moreover, a kinetic study of ursolic acid release from the obtained systems was conducted. All of the studied UA-loaded systems were well tolerated by keratinocyte cells and had suitable pH values and stability over time. The obtained formulations exhibit an apparent viscosity, ensuring the appropriate time of contact with the skin, ease of spreading, soft consistency, and adherence to the skin, which was confirmed by texture tests. The release of ursolic acid from each of the formulations is followed by a slow, controlled release according to the Korsmeyer-Peppas and Higuchi models. The elaborated systems could be considered suitable vehicles to deliver triterpene to psoriatic skin.

Freeze-Dried Camelina Lipid Droplets Loaded with Human Basic Fibroblast Growth Factor-2 Formulation for Transdermal Delivery: Breaking through the Cuticle Barrier to Accelerate Deep Second-Degree Burn Healing

Transdermal administration of chemo therapeutics into burn healing may be an effective treatment to reduce toxic side effects and improve patient compliance for burns. As a transdermal delivery system, Camelina lipid droplets (CLDs) have received great attention due to their biocompatibility, high drug payload, and rapid absorption. However, the absorbed-related mechanisms of Camelina lipid droplets have not yet been reported. Thus, this paper not only demonstrated that CLD can accelerate skin burn healing through promoting hFGF2 absorption, but also elucidated the mechanism between the skin tissue and keratinocytes using Franz, HE staining, DSC, FTIR spectroscopy, and atomic force microscopy with the presence of CLD-hFGF2 freeze-dried powder. We found that the cumulative release rate of CLD-hFGF2 freeze-dried powder was significantly higher than that of free hFGF2 freeze-dried powder into the skin. At the same time, CLD can change the structure and content of lipids and keratin to increase the permeability of hFGF2 freeze-dried powder in skin tissue. Unlike the free state of hFGF2, the biophysical properties of single cells, including height and adhesion force, were changed under CLD-hFGF2 freeze-dried powder treatment. Meanwhile, CLD-hFGF2 freeze-dried powder was more easily taken up through keratinocytes without damaging cell integrity, which provided a new viewpoint for understanding the absorption mechanism with the CLD system for cellular physiology characteristics. Overall, our findings demonstrated that CLD could break through the stratum corneum (SC) barrier and elucidated the transport mechanism of lipid droplets in skin tissue, which provides a crucial guideline in drug delivery applications for future engineering.

Development and Characterization of a Hydrogel Containing Curcumin-Loaded Nanoemulsion for Enhanced In Vitro Antibacteria and In Vivo Wound Healing

Curcumin (CUR) is a natural compound extracted from turmeric (Curcuma longa L.) used to cure acne, wound healing, etc. Its disadvantages, such as poor solubility and permeability, limit its efficacy. Nanoemulsion (NE)-based drug delivery systems have gained popularity due to their advantages. This study aimed to optimize a CUR-NE-based gel and evaluate its physicochemical and biological properties. A NE was prepared using the catastrophic phase inversion method and optimized using the Design Expert 12.0 software. The CUR-NE gel was characterized in terms of visual appearance, pH, drug release, antibacterial and wound healing effects. The optimal formulation contained CUR, Capryol 90 (oil), Labrasol:Cremophor RH40 (1:1) (surfactants), propylene glycol (co-surfactant), and water. The NE had a droplet size of 22.87 nm and a polydispersity index of 0.348. The obtained CUR-NE gel had a soft, smooth texture and a pH of 5.34 ± 0.05. The in vitro release of CUR from the NE-based gel was higher than that from a commercial gel with nanosized CUR (21.68 ± 1.25 µg/cm2, 13.62 ± 1.63 µg/cm2 after 10 h, respectively). The CUR-NE gel accelerated in vitro antibacterial and in vivo wound healing activities as compared to other CUR-loaded gels. The CUR-NE gel has potential for transdermal applications.

Nanotechnology-Based Topical Delivery of Natural Products for the Management of Atopic Dermatitis

Atopic dermatitis (AD) is a chronic eczematous inflammatory disease that may arise from environmental, genetic, and immunological factors. Despite the efficacy of current treatment options such as corticosteroids, such approaches are mainly focused on symptom relief and may present certain undesirable side effects. In recent years, isolated natural compounds, oils, mixtures, and/or extracts have gained scientific attention because of their high efficiency and moderate to low toxicity. Despite their promising therapeutic effects, the applicability of such natural healthcare solutions is somewhat limited by their instability, poor solubility, and low bioavailability. Therefore, novel nanoformulation-based systems have been designed to overcome these limitations, thus enhancing the therapeutic potential, by promoting the capacity of these natural drugs to properly exert their action in AD-like skin lesions. To the best of our knowledge, this is the first literature review that has focused on summarizing recent nanoformulation-based solutions loaded with natural ingredients, specifically for the management of AD. We suggest that future studies should focus on robust clinical trials that may confirm the safety and effectiveness of such natural-based nanosystems, thus paving the way for more reliable AD treatments.

Liquid crystalline nanoparticles enable a multifunctional approach for topical psoriasis therapy by co-delivering triptolide and siRNAs

Liquid crystalline nanoparticles (LCNs) are an attractive drugs topical delivery system due to the great internal ordering, wide interfacial area and structural similarities with the skin. In this work, LCNs were designed to encapsulate triptolide (TP) and to complex on its surface small interfering RNAs (siRNA) targeting TNF-α and IL-6, aiming at topical co-delivery and regulating multi-targets in psoriasis. These multifunctional LCNs showed appropriate physicochemical properties for topical application, such as a mean size of 150 nm, low polydispersion, TP encapsulation greater than 90% and efficient complexation with siRNA. The internal reverse hexagonal mesostructure of LCNs was confirmed by SAXS while their morphology was assessed by cryo-TEM. In vitro permeation studies revealed an increase of more than 20-fold in the distribution of TP through the porcine epidermis/dermis was achieved after the application of LCN-TP or LCN TP in hydrogel. In cell culture, LCNs showed good compatibility and rapid internalization, which was attributed to macropinocytosis and caveolin-mediated endocytosis. Anti-inflammatory potential of multifunctional LCNs was assessed by reducing of TNF-α, IL-6, IL-1β and TGF-β1 levels in LPS-stimulated macrophages. These results support the hypothesis that the co-delivery of TP and siRNAs by LCNs may be a new strategy for psoriasis topical therapy.

Pharmacokinetic Study of Triptolide Nanocarrier in Transdermal Drug Delivery System-Combination of Experiment and Mathematical Modeling

Compared with traditional oral and injection administration, the transdermal administration of traditional Chinese medicine has distinctive characteristics and advantages, which can avoid the "first pass effect" of the liver and the destruction of the gastrointestinal tract, maintain a stable blood concentration, and prolong drug action time. However, the basic theory and technology research in transdermal drug delivery are relatively limited at present, especially regarding research on new carriers of transdermal drug delivery and pharmacokinetic studies of the skin, which has become a bottleneck of transdermal drug delivery development. Triptolide is one of the main active components of Tripterygium wilfordii, which displays activities against mouse models of polycystic kidney disease and pancreatic cancer but its physical properties and severe toxicity limit its therapeutic potential. Due to the previously mentioned advantages of transdermal administration, in this study, we performed a detail analysis of the pharmacokinetics of a new transdermal triptolide delivery system. Triptolide nanoemulsion gels were prepared and served as new delivery systems, and the ex vivo characteristics were described. The metabolic characteristics of the different triptolide transdermal drug delivery formulations were investigated via skin-blood synchronous microdialysis combined with LC/MS. A multiscale modeling framework, molecular dynamics and finite element modeling were adopted to simulate the transport process of triptolide in the skin and to explore the pharmacokinetics and mathematical patterns. This study shows that the three-layer model can be used for transdermal drug delivery system drug diffusion research. Therefore, it is profitable for transdermal drug delivery system design and the optimization of the dosage form. Based on the drug concentration of the in vivo microdialysis measurement technology, the diffusion coefficient of drugs in the skin can be more accurately measured, and the numerical results can be verified. Therefore, the microdialysis technique combined with mathematical modeling provides a very good platform for the further study of transdermal delivery systems. This research will provide a new technology and method for the study of the pharmacokinetics of traditional Chinese medicine transdermal drug delivery. It has important theoretical and practical significance in clarifying the metabolic transformation of percutaneous drug absorption and screening for appropriate drugs and dosage forms of transdermal drug delivery.

Recent Trends in Nanocarriers for the Management of Atopic Dermatitis

BACKGROUND

Atopic dermatitis (AD) is a pruritic inflammatory skin condition with increasing global prevalence, almost affecting 15% to 30% of children and 5% of adults. AD results due to a complex interaction between the impaired skin barrier function, allergens, and immunological cells. Topical corticosteroids or calcineurin inhibitors in the form of creams or ointments are the mainstay of therapy, but they have low skin penetration and skin barrier repair efficiency.

OBJECTIVE

The above limitations of conventional dosage forms have motivated the development of nanoformulations of drugs for improved penetration and deposition in the skin for better management of AD.

METHODS

Databases, such as Pubmed, Elsevier, and Google Scholar, were reviewed for the investigations or reviews published related to the title.

RESULTS

The present review discusses the advantages of nanoformulations for the management of AD. Further, it also discusses the various types of topically investigated nanoformulations, i.e., polymeric nanoparticles, inorganic nanoparticles, solid lipid nanoparticles, liposomes, ethosomes, transfersomes, cubosomes, and nanoemulsion for the management of atopic dermatitis. In addition, it also discusses advancements in nanoformulations, such as nanofibres, nanosponges, micelles, and nanoformulations embedded textiles development for the management of AD.

CONCLUSION

The nanoformulations of drugs can be a better alternative for the topical management of AD with enhanced skin penetration and deposition of drugs with reduced systemic side effects and better patient compliance.

Transdermal delivery of inflammatory factors regulated drugs for rheumatoid arthritis

Rheumatoid arthritis is a chronic autoimmune disease, with the features of recurrent chronic inflammation of synovial tissue, destruction of cartilage, and bone erosion, which further affects joints tissue, organs, and systems, and eventually leads to irreversible joint deformities and body dysfunction. Therapeutic drugs for rheumatoid arthritis mainly reduce inflammation through regulating inflammatory factors. Transdermal administration is gradually being applied to the treatment of rheumatoid arthritis, which can allow the drug to overcome the skin stratum corneum barrier, reduce gastrointestinal side effects, and avoid the first-pass effect, thus improving bioavailability and relieving inflammation. This paper reviewed the latest research progress of transdermal drug delivery in the treatment of rheumatoid arthritis, and discussed in detail the dosage forms such as gel (microemulsion gel, nanoemulsion gel, nanomicelle gel, sanaplastic nano-vesiclegel, ethosomal gel, transfersomal gel, nanoparticles gel), patch, drug microneedles, nanostructured lipid carrier, transfersomes, lyotropic liquid crystal, and drug loaded electrospinning nanofibers, which provide inspiration for the rich dosage forms of transdermal drug delivery systems for rheumatoid arthritis.

Ex vivo UV-vis and FTIR photoacoustic spectroscopy of natural nanoemulsions from cellulose nanocrystals and saponins topically applied into the skin: Diffusion rates and physicochemical evaluation

Nanoemulsions are increasingly gaining importance in the development of topically applied medicine and cosmetic products because their small droplets favor the penetration rates of active compounds into the body. In this scenario, the measurements of their diffusion rates as well as eventual physicochemical changes in the target tissues are of utmost importance. It is also recognized that the use of natural surfactants can avoid allergic reactions as frequently observed for synthetic products. The natural saponins extracted from Sapindus Saponaria have the property of forming foam and are exploited as biocompatible and biodegradable, while cellulose nanocrystals are known to increase the stability of a formulation avoiding the coalescence of drops at the interface. Therefore, nanoemulsions combining natural saponins and cellulose nanocrystals are promising systems that may facilitate greater diffusion rates of molecules into the skin, being candidates to substitute synthetic formulations. This study applied the Photoacoustic Spectroscopy technique to measure the diffusion rates and the physicochemical properties of nanoemulsified formulations containing saponins and cellulose nanocrystals topically applied to the skin. The ex vivo study combined the first-time photoacoustic measurements performed in both ultraviolet-visible and mid-infrared spectral regions. The toxicity of these formulations in L929 cells was also evaluated. The results showed that the formulations were able to propagate throughout the skin to a depth of approximately 756 μm, reaching the dermal side. The non-observation of absorbing band shifting or new bands in the FTIR spectra suggests that there were no structural changes in the skin as well as in the formulations after the nanoemulsions administration. The cytotoxicity results showed that the increase of cellulose nanocrystals concentration decreased cellular toxicity. In conclusion, the results demonstrated the advantage of combining photoacoustic methods in the ultraviolet-visible and mid-infrared spectral regions to analyze drug diffusion and interaction with the skin tissues. Both methods complement each other, allowing the confirmation of the nanoemulsion diffusion through the skin and also suggesting there were no detectable physicochemical changes in the tissues. Formulations stabilized with saponins and cellulose nanocrystals showed great potential for the development of topically administered cosmetics and drugs.

Preparation of Triptolide Nano Drug Delivery System and Its Antitumor Activity In-Vitro

Triptolide (as an effective antitumor drug) is limited in clinical application because of its poor solubility and absorption in-vivo. Herein, we prepared folic acid modified polymer micelles to encapsulate triptolide and enhance its biologicalavailability coupled with antitumor effect. We prepared nano-micelles of triptolide through thin lipid film hydrational method. Physical properties and in vitro release characterization of Fol-Plla-cl-Peg-Plla-cl-Tmicelles were evaluated, while bioavailability of the formulation in rats was investigated. Tumor targeting potential of micelles was determined by observing the uptake of A549 cells. In-Vitro antitumor activity of micelles and free triptolide (API) was investigated with MTT assay. The prepared polymer material exhibited no cytotoxicity. The particle size distribution of Fol-Plla-cl-Peg-Plla-cl-T micelles was uniform and small, with good stability and high efficiency of entrapment. Triptolide In-Vitro release from micelles demonstrated slow and continuous released for 24 h. Compared with API, the half-life of micelles was prolonged, whilst its bioavailability in-vivo was increased by about 6.35 times. More importantly, Fol-Plla-cl-Peg-Plla-cl-T micelles significantly improved the antitumor activity of triptolide and showed good tumor targeting potential. Fol-Plla-cl-Peg-Plla-cl-T micelles could improve the bioavailability and antitumor activity of triptolide, amid demonstration of good tumor targeting and high safety.

Novel Curcumin-Encapsulated α-Tocopherol Nanoemulsion System and Its Potential Application for Wound Healing in Diabetic Animals

Objective

This project was aimed at formulating a novel nanoemulsion system and evaluating it for open incision wound healing in diabetic animals.

Methods

The nanoemulsions were characterized for droplet size and surface charge, drug content, antioxidant and antimicrobial profiling, and wound healing potential in diabetic animals. The skin samples excised were also analyzed for histology, mechanical strength, and vibrational and thermal analysis.

Results

The optimized nanoemulsion (CR-NE-II) exhibited droplet size of26.76 ± 0.9 nm with negative surface charge (−10.86 ± 1.06 mV), was homogenously dispersed with drug content of68.05 ± 1.2%, released almost82.95 ± 2.2%of the drug within first 2 h of experiment with synergistic antioxidant (95 ± 2.1%) and synergistic antimicrobial activity against selected bacterial strains in comparison to blank nanoemulsion, and promoted significantly fast percent reepithelization (96.47%). The histological, vibrational, thermal, and strength analysis of selected skin samples depicted a uniform and even distribution of collagen fibers which translated into significant increase in strength of skin samples in comparison to the control group.

Conclusions

The optimized nanoemulsion system significantly downregulated the oxidative stress, enhanced collagen deposition, and precluded bacterial contamination of wound, thus accelerating the skin tissue regeneration process.

Nanoemulsion-based dosage forms for the transdermal drug delivery applications: A review of recent advances

INTRODUCTION

Nanoemulsion-based drug delivery approaches have witnessed massive acceptance over the years and acquired a significant foothold owing to their tremendous benefits over the others. It has widely been used for transdermal delivery of hydrophobic and hydrophilic drugs with solubility, lipophilicity, and bioavailability issues.

AREAS COVERED

The review highlights the recent advancements and applications of transdermal nanoemulsions. Their utilities and characteristics, clinical pertinence showcasing intellectual properties and advancements, potential in treating disorders accompanying liquid, semisolid, and solid dosage forms, the ability to modulate a drug's physicochemical properties, and regulatory status are thoroughly summarized.

EXPERT OPINION

Despite tremendous therapeutic utilities and extensive investigations, this field of transdermal nanoemulsion-based technologies yet tackles several challenges such as optimum use of surfactant mixtures, economic burden due to high energy consumption during production, lack of concrete regulatory requirement, etc. Provided with the concrete guidelines on the safe use of surfactants, stability, use of scalable and economical methods, and the use of NE as a transdermal system would solve the purpose best as nanoemulsion shows remarkable improvement in drug release profiles and bioavailability of many drugs. Nevertheless, a better understanding of nanoemulsion technology holds a promising outlook and would land more opportunities and better delivery outcomes.

Development of Chitosan-Based Nanoemulsion Gel Containing Microbial Secondary Metabolite with Effective Antifungal Activity: In vitro and in vivo Characterizations

Purpose

Microbial resistance to antibiotics is one of the most important public health concerns of the 21^st century. We isolated, purified, and structurally elucidated antifungal secondary metabolites from red soil microbes and encapsulated them into chitosan (CS)-based nanoemulsion (NE) gel (NEG).

Methods

Three compounds were isolated and purified of which only one compound (Pure 2) showed potent antifungal activity (MFC: 8–132 µg/mL), which was also significantly (P<0.05) more efficient than fluconazole (MFC: 32–132 µg/mL). Pure 2 was structurally elucidated using 1D- and 2D-NMR before its incorporation into NEG. The formulations were prepared by high-speed homogenization technique. Physicochemical and pharmacological characterizations of formulations (ie, droplet size, PDI, zeta potential, drug content, viscosity, SEM, FTIR, spreadability, in vitro drug release, ex vivo permeation, in vitro antifungal and in vivo antifungal activities) were assessed.

Results

NMR analyses identified the compound as a derivative of phthalic acid ester (PAE). The optimized formulations displayed a droplet size <100 nm, -ve zeta potential, and PDI <0.45. The drug content was within the official limit of pharmacopeia (ie, 100±10%). Insignificant changes (P>0.05) in the viscosity of the formulations stored were observed. The morphology of the formulations indicated mesh-like structure. The FTIR study indicated that there were no interactions between the drug and other ingredients of the formulations. Optimum spreadability was observed in all formulations. NEG released 75.3±1.12% of Pure 2 after 12 hrs while NE released 85.33±1.88% of the compound. The skin permeation of F2 (71.15±1.28%) was significantly different (P<0.05) from F3 (81.80±1.91%) in rabbits. Complete and apparently safe recovery from the fungal infection was achieved in rabbits treated topically with Pure 2-loaded NEGs.

Conclusion

Hence, the NEG-loaded PAE isolated from Pseudomonas fluorescens represents a possible alternative for the treatment of fungal infections as compared to available therapies.

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.

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

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

Development and in vitro and in vivo evaluations of a microemulsion formulation for the oral delivery of oxaprozin

BACKGROUND

Oxaprozin is labeled as a Class II drug in the biopharmaceutical classification system, and its poor solubility in the entire gastrointestinal tract may be the main reason for its poor oral absorption capacity.

OBJECTIVE

The purpose of this study was to develop an oxaprozin formulation to enhance its oral absorption.

METHOD

Oxaprozin-loaded microemulsions were prepared using the titration method and pseudoternary phase diagram. Characterization experiments were performed on microemulsion preparations, including pH, particle size, shape, zeta potential and stability (thermodynamic, dilution, and differential scanning calorimetry). Then, the in vitro release of the microemulsion and in vivo pharmacokinetics in rats were evaluated.

RESULTS

Several microemulsion formulations were prepared. The optimal formulation was 15% oleoyl macrogolglycerides, 35% Tween 20/isopropanol (Km=2) and 50% distilled water. Its particle size met the requirements, and it had a spherical shape with a negatively charged surface. This microemulsion-loaded drug was applied to in vitro release and in vivo pharmacokinetic experiments at 7.47 mg/mL. In vitro release of the oxaprozin-loaded microemulsion best fit the first-order model, while the microemulsion preparation had a certain sustained release effect. In vivo pharmacokinetic experiments indicated that the microemulsion formulation significantly delayed the peak time of the blood concentration and simultaneously prolonged the half-life of drug elimination.

CONCLUSION

The obtained data revealed satisfactory results for this novel microemulsion of oxaprozin, which is very meaningful for clinical trials.

Optical Coherence Tomography and Microdialysis for Microneedle-Mediated Penetration Enhancement Study of Paeoniflorin-Loaded Ethosomes

BACKGROUND

To understand the cumulative effect of topical formulations after medication, evaluate the therapeutic effect of microneedle-assisted (MN-assisted) paeoniflorin-loaded ethosomes (TGP-E), and explore the potential for deep penetration of drugs, this paper uses microdialysis to systematically study the percutaneous pharmacokinetics of TGP-E.

METHODS

First, optical coherence tomography (OCT) was used to study the effectiveness of microneedle puncture. Second, a microdialysis method and a UPLC-MS method for determining the amount of paeoniflorin (Pae) in dialysate were established. Finally, the transdermal pharmacokinetics of TGP-E was studied using in vivo microdialysis in rats under the above MN-assisted conditions.

RESULTS

The optimal MN-assisted conditions were obtained at a microneedle length of 500 μm, a pressure of 3 N, and an action time of 3 min. The pharmacokinetic results demonstrated that the maximum drug concentration (Cmax) and the area under the curve (AUC) of the TGP-E gel were higher than the TGP-saline solution gel, and the mean retention time was lower. These indicated that microneedle can promote the entry of the ethosomes into the skin for in vivo experiments and greatly improve the possibility of deep penetration of the water-soluble Pae.

CONCLUSION

Therefore, the microneedle-ethosomes delivery system is a more ideal means for promoting the deep penetration of Pae. These findings may provide a reference for the combination of multiple penetration-enhancement ways to promote drug absorption, and also provide a new insight to realize the development of novel, safe, and more effective dosage forms and administration routes of drugs.

Recent Advances in Nanomaterials for Dermal and Transdermal Applications

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

Emerging Nanomedicines for the Treatment of Atopic Dermatitis

Globally, the prevalence of Atopic dermatitis (AD) is significantly increasing and affecting around 20% of population including children. Complex interactions amongst abnormality in epidermal barrier function, environment, infectious agents and immunological defects are considered as key factors in the pathogenesis of AD. Although the role of oxidative stress has been studied in some skin diseases, investigation of the same in AD is intermittent. Calcineurin inhibitors and/or topical corticosteroids are currently available; however, it causes atrophy of the skin, burning sensation, and systemic side effects which leads to poor patient compliance. These limitations provoke the strong need to develop an innovative approach in managing AD. Nanomaterials for effective drug delivery to skin conditions such as AD have attracted a lot of attention owing to its ability to encapsulate, protect, and release the cargo at the diseased skin site. However, there are lots of unmet challenges especially in terms of development of non-toxic formulations and clinical translation of established nanomedicines in the form of accessible products. Numerous formulations have emerged as carrier for poorly soluble and permeable drugs, viz., lipidic, polymeric, metal, silica, liposomes, hydrocarbon gels and this field is evolving. This review is intended to provide an insight incidences associated with pathophysiology of AD and challenges with existing treatments of AD. Focus is kept on reviewing current development and emerging nanomedicines for effective treatment of AD. The review also inculcates merits of several nanomedicines in overcoming challenges of existing products and its future implications.

Triptolide delivery: Nanotechnology-based carrier systems to enhance efficacy and limit toxicity

Triptolide (TP) possesses a wide range of biological and pharmacological activities involved in the treatment of various diseases. However, widespread usages of TP raise the urgent issues of the severe toxicity, which hugely limits its further clinical application. The novel functional nanostructured delivery system, which is of great significance in enhancing the efficacy, reducing side effects and improving bioavailability, could improve the enrichment, penetration and controlled release of drugs in the lesion location. Over the past decades, considerable efforts have been dedicated to designing and developing a variety of TP delivery systems with the intention of alleviating the adverse toxicity effects and enhancing the bioavailability. In this review, we briefly summarized and discussed the recent functionalized nano-TP delivery systems for the momentous purpose of guiding further development of novel TP delivery systems and providing perspectives for future clinical applications.

Topical Administration of Terpenes Encapsulated in Nanostructured Lipid-Based Systems

Terpenes are a group of phytocompounds that have been used in medicine for decades owing to their significant role in human health. So far, they have been examined for therapeutic purposes as antibacterial, anti-inflammatory, antitumoral agents, and the clinical potential of this class of compounds has been increasing continuously as a source of pharmacologically interesting agents also in relation to topical administration. Major difficulties in achieving sustained delivery of terpenes to the skin are connected with their low solubility and stability, as well as poor cell penetration. In order to overcome these disadvantages, new delivery technologies based on nanostructures are proposed to improve bioavailability and allow controlled release. This review highlights the potential properties of terpenes loaded in several types of lipid-based nanocarriers (liposomes, solid lipid nanoparticles, and nanostructured lipid carriers) used to overcome free terpenes' form limitations and potentiate their therapeutic properties for topical administration.

Transdermal Delivery Systems of Natural Products Applied to Skin Therapy and Care

Natural products are favored because of their non-toxicity, low irritants, and market reacceptance. We collected examples, according to ancient wisdom, of natural products to be applied in transdermal delivery. A transdermal delivery system, including different types of agents, such as ointments, patches, and gels, has long been used for skin concerns. In recent years, many novel transdermal applications, such as nanoemulsions, liposomes, lipid nanoparticles, and microneedles, have been reported. Nanosized drug delivery systems are widely applied in natural product deliveries. Nanosized materials notably enhance bioavailability and solubility, and are reported to improve the transdermal permeation of many substances compared with conventional topical formulations. Natural products have been made into nanosized biomaterials in order to enhance the penetration effect. Before introducing the novel transdermal applications of natural products, we present traditional methods within this article. The descriptions of novel transdermal applications are classified into three parts: liposomes, emulsions, and lipid nanoparticles. Each section describes cases that are related to promising natural product transdermal use. Finally, we summarize the outcomes of various studies on novel transdermal agents applied to skin treatments.

Nanocarriers for treatment of dermatological diseases: Principle, perspective and practices

Skin diseases are the fourth leading non-fatal skin conditions that act as a burden and affect the world economy globally. This condition affects the quality of a patient's life and has a pronounced impact on both their physical and mental state. Treatment of these skin conditions with conventional approaches shows a lack of efficacy, long treatment duration, recurrence of conditions, systemic side effects, etc., due to improper drug delivery. However, these pitfalls can be overcome with the applications of nanomedicine-based approaches that provide efficient site-specific drug delivery at the target site. These nanomedicine-based strategies are evolved as potential treatment opportunities in the form of nanocarriers such as polymeric and lipidic nanocarriers, nanoemulsions along with emerging others viz. carbon nanotubes for dermatological treatment. The current review focuses on challenges faced by the existing conventional treatments along with the topical therapeutic perspective of nanocarriers in treating various skin diseases. A total of 213 articles have been reviewed and the application of different nanocarriers in treating various skin diseases has been explained in detail through case studies of previously published research works. The toxicity related aspects of nanocarriers are also discussed.

Finite Element Analysis for Predicting Skin Pharmacokinetics of Nano Transdermal Drug Delivery System Based on the Multilayer Geometry Model

Background

Skin pharmacokinetics is an indispensable indication for studying the drug fate after administration of transdermal drug delivery systems (TDDS). However, the heterogeneity and complex skin structured with stratum corneum, viable epidermis, dermis, and subcutaneous tissue inevitably leads the drug diffusion coefficient (Kp) to vary depending on the skin depth, which seriously limits the development of TDDS pharmacokinetics in full thickness skin.

Methods

A multilayer geometry skin model was established and the Kp of drug in SC, viable epidermis, and dermis was obtained using the technologies of molecular dynamics simulation, in vitro permeation experiments, and in vivo microdialysis, respectively. Besides, finite element analysis (FEA) based on drug Kps in different skin layers was applied to simulate the paeonol nanoemulsion (PAE-NEs) percutaneous dynamic penetration process in two and three dimensions. In addition, PAE-NEs skin pharmacokinetics profile obtained by the simulation was verified by in vivo experiment.

Results

Coarse-grained modeling of molecular dynamic simulation was successfully established and the Kp of PAE in SC was 2.00×10⁻⁶ cm²/h. The Kp of PAE-NE in viable epidermis and in dermis detected using penetration test and microdialysis probe technology, was 1.58×10⁻⁵ cm²/h and 3.20×10⁻⁵ cm²/h, respectively. In addition, the results of verification indicated that PAE-NEs skin pharmacokinetics profile obtained by the simulation was consistent with that by in vivo experiment.

Discussion

This study demonstrated that the FEA combined with the established multilayer geometry skin model could accurately predict the skin pharmacokinetics of TDDS.

Stem cell membrane-coated isotretinoin for acne treatment

Background

Topical isotretinoin is commonly used to treat acne. However, topical isotretinoin has side effects and can hardly permeate through the stratum corneum, the most important skin barrier. Therefore, this study aimed to demonstrate the efficacy of nanoparticles as stable carriers with great curative effects, low side effects, and strong transdermal ability.

Results

In a rabbit model of hyperkeratinization, STCM-ATRA-NPs showed significant therapeutic efficacy. By contrast, negative therapeutic efficacy was observed in a golden hamster model of hyper sebum production. Scanning electron microscopy and Fourier transform infrared spectral analyses showed that nanoparticles could penetrate the stratum corneum. Western blotting demonstrated that the nanoparticles could enhance the transdermal efficacy of isotretinoin by reducing the effect of keratin and tight junction proteins. Further, nanoparticles enhanced endocytosis, thereby promoting drug penetration and absorption into the skin.

Conclusion

STCM-ATRA-NPs were demonstrated to control isotretinoin release, reducing its side effects, and efficiently permeating through the skin by reducing the effect of keratin and tight junction proteins and enhancing endocytosis.

Improved antibacterial activity of topical gel-based on nanosponge carrier of cinnamon oil

Introduction: Cinnamon essential oil (CEO) is a volatile oil, obtained from Cinnamomum zeylanicum has become one of the most important natural oil due to its antimicrobial activity. CEO suffers from various limitations such as instability and skin irritation. This problem has been overcome by formulating CEO-loaded nanosponges incorporated in carbopol gel with increased antimicrobial property and reduced skin irritation.

Methods: The nanosponges were fabricated by solvent emulsion diffusion method and evaluated for Fourier transform infrared spectroscopy (FTIR) studies, particle size, field emission scanning electron microscopy studies (FE-SEM), in vitro dissolution studies, in vitro antibacterial studies, using agar diffusion method, in vivo antibacterial activity and skin irritation studies and stability studies.

Results: Nanosponge NS1 batch was found to be in the nanosize range. FTIR studies confirmed the absence of drug-polymer interaction. NS1 confirmed a porous structure with a uniform spherical shape using FE-SEM studies. In vitro dissolution studies of optimized NS1 revealed 80% drug release in 5 h whereas, incorporating the formulation into carbopol gel showed 100% release in 5h from G1 formulation. In vitro antibacterial study of the nanosponge (NS1 and NS3) showed remarkable antibacterial activity as seen from the zone of inhibition and gel formulation G1 also showed the highest zone of inhibition with 50±1.2 mm. NS1 and G1 were stable for 2 months under accelerated conditions and 3 months under room temperature conditions. Furthermore, the in vivo and skin irritation studies were performed with selected formulation against Staphylococcus aureus , where the results confirmed the significant antimicrobial activity with no skin irritation.

Conclusion: Nanosponge carriers can be more therapeutically effective for essential oils which can further be incorporated into topical gels for convenient application.

Advancement of Lipid-Based Nanocarriers and Combination Application with Physical Penetration Technique

On account of the advantages of transdermal delivery and the application situation of transcutaneous technology in transdermal delivery, the article critically comments on nanosystems as permeation enhancement model. Nanosystems possess great potential for transcutaneous drug delivery. This review focuses on recent advances in lipid-based nanocarriers, including liposome, transfersomes, ethosomes, nanoemulsions, solid lipid nanoparticles, nanostructured lipid carriers and combination application of the lipid-based nanocarriers with microneedle, iontophoresis, electroporation and sonophoresis in the field for the development of the transdermal drug delivery system. We attempted to give an overview of lipid-based nanocarriers with the aim to improve transdermal and dermal drug delivery. A special focus is given to the nanocarrier composition, characteristic and interaction mechanisms through the skin. Recent combination applications of lipid-based nanocarriers with the physical penetration technology demonstrate the superiority of the combined use of nanocarriers and physical methods in drug penetration enhancement compared to their single use. In the future, lipidbased nanocarriers will play a greater role in the field of transdermal and dermal drug delivery.

Nanoemulsion: A Review on Mechanisms for the Transdermal Delivery of Hydrophobic and Hydrophilic Drugs

Nanoemulsions (NEs) are colloidal dispersions of two immiscible liquids, oil and water, in which one is dispersed in the other with the aid of a surfactant/co-surfactant mixture, either forming oil-in-water (o/w) or water-in-oil (w/o) nanodroplets systems, with droplets 20–200 nm in size. NEs are easy to prepare and upscale, and they show high variability in their components. They have proven to be very viable, non-invasive, and cost-effective nanocarriers for the enhanced transdermal delivery of a wide range of active compounds that tend to metabolize heavily or suffer from undesirable side effects when taken orally. In addition, the anti-microbial and anti-viral properties of NE components, leading to preservative-free formulations, make NE a very attractive approach for transdermal drug delivery. This review focuses on how NEs mechanistically deliver both lipophilic and hydrophilic drugs through skin layers to reach the blood stream, exerting the desired therapeutic effect. It highlights the mechanisms and strategies executed to effectively deliver drugs, both with o/w and w/o NE types, through the transdermal way. However, the mechanisms reported in the literature are highly diverse, to the extent that a definite mechanism is not conclusive.

Transdermal delivery of fluvastatin loaded nanoemulsion gel: Preparation, characterization and in vivo anti-osteoporosis activity

The objective of present study was to develop hydrogel based nanoemulsion (NE) drug delivery system for transdermal delivery and evaluate its potential in in vivo anti-osteoporotic activity. NE was prepared using aqueous phase titration method and characterized for droplet size, zeta potential and morphology. It was then formulated into hydrogel based NE gel using carbopol 940 as gelling agent. NE gel was evaluated for pH, viscosity, in vitro/ex vivo permeation studies and in vivo anti-osteoporotic activity. The results indicated formation of spherical, nano sized globules of NE ranging from 11.17 ± 0.24 to 128.8 ± 0.16 nm with polydispersity of <0.5. In vitro and ex vivo permeation studies showed significantly higher permeation of NE as well as NE gel in comparison to fluvastatin solution indicating that NE gel can effectively penetrate through skin layers. In vivo anti-osteoporotic results demonstrated formation of new bone in trabecular region of osteoporotic rat femurs through micro-CT scanning radiographs. Biomechanical strength testing demonstrated greater load bearing capacity of rat femurs in the treated animals in comparison with the osteoporotic group. Thus, developed NE gel formulation of fluvastatin demonstrated greater potential for transdermal delivery and in the treatment of osteoporosis.

In Vitro Drug Dissolution/Permeation Testing of Nanocarriers for Skin Application: a Comprehensive Review

This review highlights in vitro drug dissolution/permeation methods available for topical and transdermal nanocarriers that have been designed to modulate the propensity of drug release, drug penetration into skin, and permeation into systemic circulation. Presently, a few of USFDA-approved in vitro dissolution/permeation methods are available for skin product testing with no specific application to nanocarriers. Researchers are largely utilizing the in-house dissolution/permeation testing methods of nanocarriers. These drug release and permeation methods are pending to be standardized. Their biorelevance with reference to in vivo plasma concentration-time profiles requires further exploration to enable translation of in vitro data for in vivo or clinical performance prediction.

Essential Oils and Isolated Terpenes in Nanosystems Designed for Topical Administration: A Review

Essential oils are natural products with a complex composition. Terpenes are the most common class of chemical compounds present in essential oils. Terpenes and the essential oils containing them are widely used and investigated by their pharmacological properties and permeation-enhancing ability. However, many terpenes and essential oils are sensitive to environmental conditions, undergoing volatilization and chemical degradation. In order to overcome the chemical instability of some isolated terpenes and essential oils, the encapsulation of these compounds in nanostructured systems (polymeric, lipidic, or molecular complexes) has been employed. In addition, nanoencapsulation can be of interest for pharmaceutical applications due to its capacity to improve the bioavailability and allow the controlled release of drugs. Topical drug administration is a convenient and non-invasive administration route for both local and systemic drug delivery. The present review focuses on describing the current status of research concerning nanostructured delivery systems containing isolated terpenes and/or essential oils designed for topical administration and on discussing the use of terpenes and essential oils either for their biological activities or as permeation enhancers in pharmaceutic formulations.

A novel microemulsion-based isotonic perfusate modulated by Ringer's solution for improved microdialysis recovery of liposoluble substances

Background

Microdialysis is promising technique for dynamic microbiochemical sampling from tissues. However, the application of typical aqueous perfusates to liposoluble substances is limited. In this study, a novel microemulsion (ME)-based isotonic perfusate (RS-ME) was prepared to improve the recovery of liposoluble components using microdialysis probes.

Results

Based on pseudo-ternary phase diagrams and comparisons of the ME area, Kolliphor^® EL and Transcutol^® P were selected as the surfactant and co-surfactant, respectively, with a weight ratio (Km) of 2:1 and ethyl oleate as the oil phase. The ME was mixed with Ringer’s solution at a 1:6 ratio (v/v) to obtain the isotonic RS-ME. The droplet size distribution of the ME in RS-ME was 78.3 ± 9.2 nm, with a zeta potential of − 3.5 ± 0.3 mV. By microdialysis perfusion, RS-ME achieved higher recovery rates of the poorly water-soluble compounds evodiamine (EVO) and ruthenium (RUT), i.e., 58.36 ± 0.57% and 49.40 ± 0.57%, respectively, than those of 20% (v/v) PEG 400 Ringer's solution (RS-PEG) and 10% (v/v) ethanol Ringer’s solution (RS-EtOH). In vivo microdialysis experiments confirmed that RS-ME captured EVO and RUT molecules around the dialysis membrane more efficiently and exhibited less spreading than RS-PEG and RS-EtOH.

Conclusions

Owing to the nanosized droplets formed by lipid components in the RS-ME and the limited dispersion out of the dialysis membrane, we obtained good biocompatibility and reliable dialysis results, without affecting the tissue microenvironment. As a novel perfusate, RS-ME provides an easy and reliable approach to the microdialysis sampling of fat-soluble components.

Lipid nanoparticles loading triptolide for transdermal delivery: mechanisms of penetration enhancement and transport properties

Background

In recent years, nanoparticles (NPs) including nanostructured lipid carries (NLC) and solid lipid nanoparticles (SLN) captured an increasing amount of attention in the field of transdermal drug delivery system. However, the mechanisms of penetration enhancement and transdermal transport properties of NPs are not fully understood. Therefore, this work applied different platforms to evaluate the interactions between skin and NPs loading triptolide (TPL, TPL-NLC and TPL-SLN). Besides, NPs labeled with fluorescence probe were tracked after administration to investigate the dynamic penetration process in skin and skin cells. In addition, ELISA assay was applied to verify the in vitro anti-inflammatory effect of TPL-NPs.

Results

Compared with the control group, TPL-NPs could disorder skin structure, increase keratin enthalpy and reduce the SC infrared absorption peak area. Besides, the work found that NPs labeled with fluorescence probe accumulated in hair follicles and distributed throughout the skin after 1 h of administration and were taken into HaCaT cells cytoplasm by transcytosis. Additionally, TPL-NLC could effectively inhibit the expression of IL-4, IL-6, IL-8, IFN-γ, and MCP-1 in HaCaT cells, while TPL-SLN and TPL solution can only inhibit the expression of IL-6.

Conclusions

TPL-NLC and TPL-SLN could penetrate into skin in a time-dependent manner and the penetration is done by changing the structure, thermodynamic properties and components of the SC. Furthermore, the significant anti-inflammatory effect of TPL-NPs indicated that nanoparticles containing NLC and SLN could serve as safe prospective agents for transdermal drug delivery system.