Key Transdermal Patch Using Cannabidiol-Loaded Nanocarriers with Better Pharmacokinetics in vivo.

Purpose: Cannabidiol (CBD) is a promising therapeutic drug with low addictive potential and a favorable safety profile. However, CBD did face certain challenges, including poor solubility in water and low oral bioavailability. To harness the potential of CBD by combining it with a transdermal drug delivery system (TDDS). This innovative approach sought to develop a transdermal patch dosage form with micellar vesicular nanocarriers to enhance the bioavailability of CBD, leading to improved therapeutic outcomes. Methods: A skin-penetrating micellar vesicular nanocarriers, prepared using nano emulsion method, cannabidiol loaded transdermal nanocarriers-12 (CTD-12) was presented with a small particle size, high encapsulation efficiency, and a drug-loaded ratio for CBD. The skin permeation ability used Strat-M™ membrane with a transdermal diffusion system to evaluate the CTD and patch of CTD-12 (PCTD-12) within 24 hrs. PCTD-12 was used in a preliminary pharmacokinetic study in rats to demonstrate the potential of the developed transdermal nanocarrier drug patch for future applications. Results: In the transdermal application of CTD-12, the relative bioavailability of the formulation was 3.68 ± 0.17-fold greater than in the free CBD application. Moreover, PCTD-12 indicated 2.46 ± 0.18-fold higher relative bioavailability comparing with free CBD patch in the ex vivo evaluation. Most importantly, in the pharmacokinetics of PCTD-12, the relative bioavailability of PCTD-12 was 9.47 ± 0.88-fold higher than in the oral application. Conclusion: CTD-12, a transdermal nanocarrier, represents a promising approach for CBD delivery, suggesting its potential as an effective transdermal dosage form.

Nanosuspension-Loaded Dissolving Microneedle Patches for Enhanced Transdermal Delivery of a Highly Lipophilic Cannabidiol.

Purpose: Transdermal Drug Delivery System (TDDS) offers a promising alternative for delivering poorly soluble drugs, challenged by the stratum corneum's barrier effect, which restricts the pool of drug candidates suitable for TDDS. This study aims to establish a delivery platform specifically for highly lipophilic drugs requiring high doses (log P > 5, dose > 10 mg/kg/d), to improve their intradermal delivery and enhance solubility. Methods: Cannabidiol (CBD, log P = 5.91) served as the model drug. A CBD nanosuspension (CBD-NS) was prepared using a bottom-up method. The particle size, polydispersity index (PDI), zeta potential, and concentration of the CBD-NS were characterized. Subsequently, CBD-NS was incorporated into dissolving microneedles (DMNs) through a one-step manufacturing process. The intradermal dissolution abilities, physicochemical properties, mechanical strength, insertion depth, and release behavior of the DMNs were evaluated. Sprague-Dawley (SD) rats were utilized to assess the efficacy of the DMN patch in treating knee synovitis and to analyze its skin permeation kinetics and pharmacokinetic performance. Results: The CBD-NS, stabilized with Tween 80, exhibited a particle size of 166.83 ± 3.33 nm, a PDI of 0.21 ± 0.07, and a concentration of 46.11 ± 0.52 mg/mL. The DMN loaded with CBD-NS demonstrated favorable intradermal dissolution and mechanical properties. It effectively increased the delivery of CBD into the skin, extended the action's duration in vivo, and enhanced bioavailability. CBD-NS DMN exhibited superior therapeutic efficacy and safety in a rat model of knee synovitis, significantly inhibiting TNF-α and IL-1ß compared with the methotrexate subcutaneous injection method. Conclusion: NS technology effectively enhances the solubility of the poorly soluble drug CBD, while DMN facilitates penetration, extends the duration of action in vivo, and improves bioavailability. Furthermore, CBD has shown promising therapeutic outcomes in treating knee synovitis. This innovative drug delivery system is expected to offer a more efficient solution for the administration of highly lipophilic drugs akin to CBD, thereby facilitating high-dose administration.

Transdermal Delivery of Niacin Through Polysaccharide Films Ameliorates Cutaneous Flushing in Experimental Wistar Rats.

BACKGROUND: Niacin, an established therapeutic for dyslipidemia, is hindered by its propensity to induce significant cutaneous flushing when administered orally in its unmodified state, thereby constraining its clinical utility. OBJECTIVE: This study aimed to fabricate, characterize, and assess the in-vitro and in-vivo effectiveness of niacin-loaded polymeric films (NLPFs) comprised of carboxymethyl tamarind seed polysaccharide. The primary objective was to mitigate the flushing-related side effects associated with oral niacin administration. METHODS: NLPFs were synthesized using the solvent casting method and subsequently subjected to characterization, including assessments of tensile strength, moisture uptake, thickness, and folding endurance. Surface characteristics were analyzed using a surface profiler and scanning electron microscopy (SEM). Potential interactions between niacin and the polysaccharide core were investigated through X-ray diffraction experiments (XRD) and Fourier transform infrared spectroscopy (FTIR). The viscoelastic properties of the films were explored using a Rheometer. In-vitro assessments included drug release studies, swelling behavior assays, and antioxidant assays. In-vivo efficacy was evaluated through skin permeation assays, skin irritation assays, and histopathological analyses. RESULTS: NLPFs exhibited a smooth texture with favorable tensile strength and moisture absorption capabilities. Niacin demonstrated interaction with the polysaccharide core, rendering the films amorphous. The films displayed slow and sustained drug release, exceptional antioxidant properties, optimal swelling behavior, and viscoelastic characteristics. Furthermore, the films exhibited biocompatibility and non-toxicity towards skin cells. CONCLUSION: NLPFs emerged as promising carrier systems for the therapeutic transdermal delivery of niacin, effectively mitigating its flushing-associated adverse effects.

Deep eutectic solvent self-assembled reverse nanomicelles for transdermal delivery of sparingly soluble drugs.

BACKGROUND: Transdermal delivery of sparingly soluble drugs is challenging due to their low solubility and poor permeability. Deep eutectic solvent (DES)/or ionic liquid (IL)-mediated nanocarriers are attracting increasing attention. However, most of them require the addition of auxiliary materials (such as surfactants or organic solvents) to maintain the stability of formulations, which may cause skin irritation and potential toxicity. RESULTS: We fabricated an amphiphilic DES using natural oxymatrine and lauric acid and constructed a novel self-assembled reverse nanomicelle system (DES-RM) based on the features of this DES. Synthesized DESs showed the broad liquid window and significantly solubilized a series of sparingly soluble drugs, and quantitative structure-activity relationship (QSAR) models with good prediction ability were further built. The experimental and molecular dynamics simulation elucidated that the self-assembly of DES-RM was adjusted by noncovalent intermolecular forces. Choosing triamcinolone acetonide (TA) as a model drug, the skin penetration studies revealed that DES-RM significantly enhanced TA penetration and retention in comparison with their corresponding DES and oil. Furthermore, in vivo animal experiments demonstrated that TA@DES-RM exhibited good anti-psoriasis therapeutic efficacy as well as biocompatibility. CONCLUSIONS: The present study offers innovative insights into the optimal design of micellar nanodelivery system based on DES combining experiments and computational simulations and provides a promising strategy for developing efficient transdermal delivery systems for sparingly soluble drugs.

Formulation and evaluation of miconazole lipogel for enhanced drug permeation.

Hydrophilic drugs could be incorporated into the skin surface by manes of Lipogel. This study aimed to prepare miconazole lipogel with natural ingredients to enhance drug permeability using dimethyl Sulfoxide (DMSO). The miconazole lipogels, A1 (without DMSO) and A2 (with DMSO) were formulated and evaluated for organoleptic evaluation, pH, viscosity, stability studies, freeze-thawing, drug release profile and drug permeation enhancement. Results had stated that prepared lipogel's pH falls within the acceptable range required for topical delivery (4 to 6) while both formulations show good results in organoleptic evaluation. The A2 formulation containing DMSO shows better permeation of miconazole (84.76%) on the artificial skin membrane as compared to A1 lipogel formulation (50.64%). In in-vitro drug release studies, A2 for-mulation showed 87.48% drug release while A1 showed just 60.1% drug release from lipogel. Stability studies were performed on model formulations under environmental conditions and both showed good spreadibility, stable pH, free of grittiness and good consistency in formulation. The results concluded that A2 formulation containing DMSO shows better results as compared to DMSO-free drug lipogel.

Development and comparison of machine learning models for in-vitro drug permeation prediction from microneedle patch.

The field of machine learning (ML) is advancing to a larger extent and finding its applications across numerous fields. ML has the potential to optimize the development process of microneedle patch by predicting the drug release pattern prior to its fabrication and production. The early predictions could not only assist the in-vitro and in-vivo experimentation of drug release but also conserve materials, reduce cost, and save time. In this work, we have used a dataset gleaned from the literature to train and evaluate different ML models, such as stacking regressor, artificial neural network (ANN) model, and voting regressor model. In this study, models were developed to improve prediction accuracy of the in-vitro drug release amount from the hydrogel-type microneedle patch and the in-vitro drug permeation amount through the micropores created by solid microneedles on the skin. We compared the performance of these models using various metrics, including R-squared score (R2 score), root mean squared error (RMSE), and mean absolute error (MAE). Voting regressor model performed better with drug permeation percentage as an outcome feature having RMSE value of 3.24. In comparison, stacking regressor have a RMSE value of 16.54, and ANN model has shown a RMSE value of 14. The value of permeation amount calculated from the predicted percentage is found to be more accurate with RMSE of 654.94 than direct amount prediction, having a RMSE of 669.69. All our models have performed far better than the previously developed model before this research, which had a RMSE of 4447.23. We then optimized voting regressor model's hyperparameter and cross validated its performance. Furthermore, it was deployed in a webapp using Flask framework, showing a way to develop an application to allow other users to easily predict drug permeation amount from the microneedle patch at a particular time period. This project demonstrates the potential of ML to facilitate the development of microneedle patch and other drug delivery systems.

Fabrication and in vitro characterization of curcumin film-forming topical spray: An integrated approach for enhanced patient comfort and efficacy.

Background: Curcumin, known for its anti-inflammatory properties, was selected for the developing consumer friendly film forming spray that offers precise delivery of curcumin and and improves patient adherence. Methods: An optimized film-forming solution was prepared by dissolving curcumin (1%), Eudragit RLPO (5%), propylene glycol (1%), and camphor (0.5%) in ethanol: acetone (20:80) as the solvent. The solution was filled in a spray container which contained 70% solutions and 30% petroleum gas. In-vitro characterization was performed. Results: Potential anti-inflammatory phytoconstituents were extracted from the PubChem database and prepared as ligands, along with receptor molecules (nsp10-nsp16), for molecular docking using Autodock Vina. The docking study showed the lowest binding energy of -8.2 kcal/mol indicates better binding affinities. The optimized formulation consisted of ethanol:acetone (20:80) as the solvent, Eudragit RLPO (5%) as the polymer, propylene glycol (1%) as the plasticizer, and camphor oil (0.5%) as the penetration enhancer. The optimized formulation exhibited pH of 5.8 ± 0.01, low viscosity, low film formation time (19.54 ± 0.78 sec), high drug content (8.243 ± 0.43 mg/mL), and extended ex vivo drug permeation (85.08 ± 0.09%) for nine hours. Consequently, the formulation was incorporated into a container using 30% liquefied petroleum gas, delivering 0.293 ± 0.08 mL per actuation, containing 1.53 ± 0.07 mg of the drug. The film-forming spray exhibited higher cumulative drug permeation (83.94 ± 0.34%) than the marketed cream formulation and pure drug solution after 9 h, with an enhancement ratio of 14. Notably, the film-forming spray exhibited no skin irritation and remained stable for over three months. Conclusions: The developed curcumin film-forming system is promising as a carrier for wound management because of its convenient administration and transport attributes. Further in vivo studies are required to validate its efficacy in wound management.

Influence of Surfactant on the Skin Permeation of Methylisothiazolinone and Methylchloroisothiazolinone.

Patch tests are often used in safety evaluations to identify the substance causing skin irritation, but the same substance can sometimes give positive or negative results depending on the test conditions. Here, we investigated differences in the skin penetration of two test compounds under different application conditions. We studied the effects of the anionic surfactant sodium dodecyl sulfate (SDS) and the nonionic surfactant polysorbate 80 (PS) on skin penetration of the preservatives methylisothiazolinone (MT) and methylchloroisothiazolinone (MCT), which are used in cosmetics such as shampoos. The skin permeation of MT was enhanced by SDS but was unchanged by PS. Skin impedance decreased in the presence of SDS whereas PS had the same effect as the control aqueous solution, suggesting that SDS reduction of the barrier function of skin affects the permeation of MT, a hydrophilic drug. Application of a mixture of MCT and MT in the presence of SDS did not affect the skin permeation of MCT whereas the permeation of MT was enhanced by SDS, indicating that the skin permeation of MCT is less affected by SDS than is MT. Thus, attention should be paid to the possible effect of co-solutes, especially hydrophilic drugs.

Propellant Free Pressurized Spray System of Etodolac to Manage Acute Pain Conditions: In Vitro and In Vivo Evaluation.

This study aimed to develop a propellant-free topical spray formulation of Etodolac (BCS-II), a potent NSAID, which could be beneficial in the medical field for the effective treatment of pain and inflammation conditions. The developed novel propellant-free spray formulation is user-friendly, cost-effective, propellant-free, eco-friendly, enhances the penetration of Etodolac through the skin, and has a quick onset of action. Various formulations were developed by adjusting the concentrations of different components, including lecithin, buffering agents, film-forming agents, plasticizers, and permeation enhancers. The prepared propellant-free spray formulations were then extensively characterized and evaluated through various in vitro, ex vivo, and in vivo parameters. The optimized formulation exhibits an average shot weight of 0.24 ± 0.30 ml and an average drug content or content uniformity of 87.3 ± 1.01% per spray. Additionally, the optimized formulation exhibits an evaporation time of 3 ± 0.24 min. The skin permeation study demonstrated that the permeability coefficients of the optimized spray formulation were 21.42 cm/h for rat skin, 13.64 cm/h for mice skin, and 18.97 cm/h for the Strat-M membrane. When assessing its potential for drug deposition using rat skin, mice skin, and the Strat-M membrane, the enhancement ratios for the optimized formulation were 1.88, 2.46, and 1.92, respectively against pure drug solution. The findings from our study suggest that the propellant-free Etodolac spray is a reliable and safe topical formulation. It demonstrates enhanced skin deposition, and improved effectiveness, and is free from any skin irritation concerns.

Potent drug delivery enhancement of betulinic acid and NVX-207 into equine skin in vitro - a comparison between a novel oxygen flow-assisted transdermal application device and microemulsion gels.

BACKGROUND: Gray horses are predisposed to equine malignant melanoma (EMM) with advancing age. Depending on the tumor's location and size, they can cause severe problems (e.g., defaecation, urination, feeding). A feasible therapy for EMM has not yet been established and surgical excision can be difficult depending on the location of the melanoma. Thus, an effective and safe therapy is needed. Naturally occurring betulinic acid (BA), a pentacyclic triterpene and its synthetic derivate, NVX-207 (3-acetyl-betulinic acid-2-amino-3-hydroxy-2-hydroxymethyl-propanoate) are known for their cytotoxic properties against melanomas and other tumors and have already shown good safety and tolerability in vivo. In this study, BA and NVX-207 were tested for their permeation potential into equine skin in vitro in Franz-type diffusion cell (FDC) experiments after incubation of 5 min, 30 min and 24 h, aiming to use these formulations for prospective in vivo studies as a treatment for early melanoma stages. Potent permeation was defined as reaching or exceeding the half maximal inhibitory concentrations (IC50) of BA or NVX-207 for equine melanoma cells in equine skin samples. The active ingredients were either dissolved in a microemulsion (ME) or in a microemulsion gel (MEG). All of the formulations were transdermally applied but the oil-in-water microemulsion was administered with a novel oxygen flow-assisted (OFA) applicator (DERMADROP TDA). RESULTS: All tested formulations exceeded the IC50 values for equine melanoma cells for BA and NVX-207 in equine skin samples, independently of the incubation time NVX-207 applied with the OFA applicator showed a significant time-dependent accumulation and depot-effect in the skin after 30 min and 24 h (P < 0.05). CONCLUSIONS: All tested substances showed promising results. Additionally, OFA administration showed a significant accumulation of NVX-207 after 30 min and 24 h of incubation. Further in vivo trials with OFA application are recommended.

Integrating mathematical approaches (IMAS): Novel methodology for predicting dermal absorption rates of chemicals under finite dose conditions.

Quantitative structure permeation relationship (QSPR) models have gained prominence in recent years owing to their capacity to elucidate the influence of physicochemical properties on the dermal absorption of chemicals. These models facilitate the prediction of permeation coefficient (Kp) values, indicating the skin permeability of a chemical under infinite dose conditions. Conversely, obtaining dermal absorption rates (DAs) under finite dose conditions, which are crucial for skin product safety evaluation, remains a challenge when relying solely on Kp predictions from QSPR models. One proposed resolution involves using Kroes' methodology, categorizing DAs based on Kp values; however, refinement becomes necessary owing to discreteness in the obtained values. We previously developed a mathematical model using Kp values obtained from in vitro dermal absorption tests to predict DAs. The present study introduces a new methodology, Integrating Mathematical Approaches (IMAS), which combines QSPR models and our mathematical model to predict DAs for risk assessments without conducting in vitro dermal absorption tests. Regarding 40 chemicals (76.1 ≤ MW ≤ 220; -1.4 ≤ Log Ko/w ≤ 3.1), IMAS showed that 65.0% (26/40) predictions of DA values were accurate to within twofold of the observed values in finite dose experiments. Compared to Kroes' methodology, IMAS notably mitigated overestimation, particularly for hydrophilic chemicals with water solubility exceeding 57.0 mg/cm3. These findings highlight the value of IMAS as a tool for skin product risk assessments, particularly for hydrophilic compounds.

[Development of Transdermal Formulation Based on Nanotechnology and Elucidation of Its Drug Delivery Pathways].

Transdermal drug delivery is a formulation in which the drug is absorbed through the skin for systemic action. Its advantages include avoidance of first-pass effects, sustained drug supply, and ease of administration and discontinuation. Drugs administered transdermally transfer into the blood circulation through the stratum corneum, epidermis, and dermis. The stratum corneum on the skin surface plays a barrier function in skin absorption. Therefore, developing of transdermal drug delivery systems requires innovations that overcome the barrier function of the stratum corneum and improve skin permeation. This review examines the usefulness of transdermal formulations based on solid nanoparticles using raloxifene. Milled raloxifene was gelled with (mRal-NPs) or without menthol (Ral-NPs) using Carbopol. The drug release and transdermal penetration were measured using a Franz diffusion cell, and the therapeutic evaluation of osteoporosis was determined in an ovariectomized rat model. Although the raloxifene released from Ral-NPs remained in the nanoparticle state, the skin penetration of raloxifene nanoparticles was prevented by the stratum corneum in rat. The inclusion of menthol in the formulation attenuated the barrier function of the stratum corneum and permitted raloxifene nanoparticles to penetrate through the skin. Moreover, macropinocytosis relates to the formulation's skin penetration, including menthol (mRal-NPs). Applying mRal-NPs attenuated the decreases in calcium level and stiffness of bones of ovariectomized rats. This information can support future studies aimed at designing novel transdermal formulations.

Organogels: "GelVolution" in Topical Drug Delivery - Present and Beyond.

Topical drug delivery holds immense significance in dermatological treatments due to its non-invasive nature and direct application to the target site. Organogels, a promising class of topical drug delivery systems, have acquired substantial attention for enhancing drug delivery efficiency. This review article aims to explore the advantages of organogels, including enhanced drug solubility, controlled release, improved skin penetration, non-greasy formulations, and ease of application. The mechanism of organogel permeation into the skin is discussed, along with formulation strategies, which encompass the selection of gelling agents, cogelling agents, and additives while considering the influence of temperature and pH on gel formation. Various types of organogelators and organogels and their properties, such as viscoelasticity, non-birefringence, thermal stability, and optical clarity, are presented. Moreover, the biomedical applications of organogels in targeting skin cancer, anti-inflammatory drug delivery, and antifungal drug delivery are discussed. Characterization parameters, biocompatibility, safety considerations, and future directions in optimizing skin permeation, ensuring long-term stability, addressing regulatory challenges, and exploring potential combination therapies are thoroughly examined. Overall, this review highlights the immense potential of organogels in redefining topical drug delivery and their significant impact on the field of dermatological treatments, thus paving the way for exciting prospects in the domain.

Carboxymethyl cellulose-based rotigotine nanocrystals-loaded hydrogel for increased transdermal delivery with alleviated skin irritation.

Transdermal rotigotine (RTG) therapy is prescribed to manage Parkinson's disease (Neupro® patch). However, its use is suffered from application site reactions. Herein, drug nanocrystalline suspension (NS)-loaded hydrogel (NS-HG) employing polysaccharides simultaneously as suspending agent and hydrogel matrix was constructed for transdermal delivery, with alleviated skin irritation. RTG-loaded NS-HG was prepared using a bead-milling technique, employing sodium carboxylmethyl cellulose (Na.CMC) as nano-suspending agent (molecular weight 90,000 g/mol) and hydrogel matrix (700,000 g/mol), respectively. NS-HG was embodied as follows: drug loading: ≤100 mg/mL; shape: rectangular crystalline; crystal size: <286.7 nm; zeta potential: -61 mV; viscosity: <2.16 Pa·s; and dissolution rate: >90 % within 15 min. Nuclear magnetic resonance analysis revealed that the anionic polymers bind to RTG nanocrystals via charge interaction, affording uniform dispersion in the matrix. Rodent transdermal absorption of RTG from NS-HG was comparable to that from microemulsions, and proportional to drug loading. Moreover, NS-HG was skin-friendly; erythema and epidermal swelling were absent after repeated application. Further, NS-HG was chemically stable; >95 % of the drug was preserved up to 4 weeks under long term (25 °C/RH60%), accelerated (40 °C/RH75%), and stress (50 °C) storage conditions. Therefore, this novel cellulose derivative-based nanoformulation presents a promising approach for effective transdermal RTG delivery with improved tolerability.

Transdermal Delivery of Pramipexole Using Microneedle Technology for the Potential Treatment of Parkinson's Disease.

Parkinson's disease (PD) is a debilitating neurodegenerative disease primarily impacting neurons responsible for dopamine production within the brain. Pramipexole (PRA) is a dopamine agonist that is currently available in tablet form. However, individuals with PD commonly encounter difficulties with swallowing and gastrointestinal motility, making oral formulations less preferable. Microneedle (MN) patches represent innovative transdermal drug delivery devices capable of enhancing skin permeability through the creation of microconduits on the surface of the skin. MNs effectively reduce the barrier function of skin and facilitate the permeation of drugs. The work described here focuses on the development of polymeric MN systems designed to enhance the transdermal delivery of PRA. PRA was formulated into both dissolving MNs (DMNs) and directly compressed tablets (DCTs) to be used in conjunction with hydrogel-forming MNs (HFMNs). In vivo investigations using a Sprague-Dawley rat model examined, for the first time, if it was beneficial to prolong the application of DMNs and HFMNs beyond 24 h. Half of the patches in the MN cohorts were left in place for 24 h, whereas the other half remained in place for 5 days. Throughout the entire 5 day study, PRA plasma levels were monitored for all cohorts. This study confirmed the successful delivery of PRA from DMNs (Cmax = 511.00 ± 277.24 ng/mL, Tmax = 4 h) and HFMNs (Cmax = 328.30 ± 98.04 ng/mL, Tmax = 24 h). Notably, both types of MNs achieved sustained PRA plasma levels over a 5 day period. In contrast, following oral administration, PRA remained detectable in plasma for only 48 h, achieving a Cmax of 159.32 ± 113.43 ng/mL at 2 h. The HFMN that remained in place for 5 days demonstrated the most promising performance among all investigated formulations. Although in the early stages of development, the findings reported here offer a hopeful alternative to orally administered PRA. The sustained plasma profile observed here has the potential to reduce the frequency of PRA administration, potentially enhancing patient compliance and ultimately improving their quality of life. This work provides substantial evidence advocating the development of polymeric MN-mediated drug delivery systems to include sustained plasma levels of hydrophilic pharmaceuticals.

Nanocarrier-Integrated Microneedles: Divulging the Potential of Novel Frontiers for Fostering the Management of Skin Ailments.

The various kinds of nanocarriers (NCs) have been explored for the delivery of therapeutics designed for the management of skin manifestations. The NCs are considered as one of the promising approaches for the skin delivery of therapeutics attributable to sustained release and enhanced skin penetration. Despite the extensive applications of the NCs, the challenges in their delivery via skin barrier (majorly stratum corneum) have persisted. To overcome all the challenges associated with the delivery of NCs, the microneedle (MN) technology has emerged as a beacon of hope. Programmable drug release, being painless, and its minimally invasive nature make it an intriguing strategy to circumvent the multiple challenges associated with the various drug delivery systems. The integration of positive traits of NCs and MNs boosts therapeutic effectiveness by evading stratum corneum, facilitating the delivery of NCs through the skin and enhancing their targeted delivery. This review discusses the barrier function of skin, the importance of MNs, the types of MNs, and the superiority of NC-loaded MNs. We highlighted the applications of NC-integrated MNs for the management of various skin ailments, combinational drug delivery, active targeting, in vivo imaging, and as theranostics. The clinical trials, patent portfolio, and marketed products of drug/NC-integrated MNs are covered. Finally, regulatory hurdles toward benchtop-to-bedside translation, along with promising prospects needed to scale up NC-integrated MN technology, have been deliberated. The current review is anticipated to deliver thoughtful visions to researchers, clinicians, and formulation scientists for the successful development of the MN-technology-based product by carefully optimizing all the formulation variables.

Safety assessment of Paeonia lactiflora root extract for a cosmetic ingredient employing the threshold of toxicological concern (TTC) approach.

Botanical extracts, widely used in cosmetics, pose a challenge to safety assessment due to their complex compositions. The threshold of toxicological concern (TTC) approach, offering a safe exposure level for cosmetic ingredients, proves to be a promising solution for ensuring the safety of cosmetic ingredients with low exposure level. We assessed the safety of Paeonia lactiflora root extract (PLR), commonly used in skin conditioning products, with the TTC. We identified 50 constituents of PLR extract from the USDA database and literature exploration. Concentration of each constituent of PLR extract was determined with the information from USDA references, literature, and experimental analysis. The genotoxicity of PLR and its constituents was assessed in vitro and in silico respectively. Cramer class of the constituents of the PLR extract was determined with Toxtree 3.1 extended decision tree using ChemTunes®. Systemic exposure of each constituent from leave-on type cosmetic products containing PLR at a 1% concentration was estimated and compared with respective TTC threshold. Two constituents exceeding TTC threshold were further analyzed for dermal absorption using in silico tools, which confirmed the safety of PLR extract in cosmetics. Collectively, we demonstrated that the TTC is a useful tool for assessing botanical extract safety in cosmetics.

Mechanisms of the Drug Penetration Enhancer Propylene Glycol Interacting with Skin Lipid Membranes.

Very few drugs have the necessary physicochemical properties to cross the skin's main permeability barrier, the stratum corneum (SC), in sufficient amounts. Propylene glycol (PG) is a chemical penetration enhancer that could be included in topical formulations in order to overcome the barrier properties of the skin and facilitate the transport of drugs across it. Experiments have demonstrated that PG increases the mobility and disorder of SC lipids and may extract cholesterol from the SC, but little is known about the molecular mechanisms of drug permeation enhancement by PG. In this work, we have performed molecular dynamics (MD) simulations to investigate the molecular-level effects of PG on the structure and properties of model SC lipid bilayers. The model bilayers were simulated in the presence of PG concentrations over the range of 0-100% w/w PG, using both an all-atom and a united atom force field. PG was found to localize in the hydrophilic headgroup regions at the bilayer interface, to occupy the lipid-water hydrogen-bonding sites, and to slightly increase lipid tail disorder in a concentration-dependent manner. We showed with MD simulation that PG enhances the permeation of small molecules such as water by interacting with the bilayer interface; the results of our study may be used to guide the design of formulations for transdermal drug delivery with enhanced skin permeation, as well as topical formulations and cosmetic products.

Developing Plant Exosomes as an Advanced Delivery System for Cosmetic Peptide.

Peptides are a promising skincare ingredient, but due to their inherent instability and the barrier function of the skin's surface, they often have limited skin absorption and penetration, which can significantly hinder their skincare benefits. To address this, a novel technique called NanoGlow has been introduced for encapsulating peptide-based cosmetic raw materials into engineered nanosized plant-derived exosomes (pExo) to achieve the goal of a healthier and more radiant skin state. In this approach, pExo served as carriers for cosmetic peptides across the intact skin barrier, enhancing their biological effectiveness in skin beauty. The NanoGlow strategy combines chemical activation and physical proencapsulation, boasting a high success rate and straightforward and stable operation, making it suitable for large-scale production. Comprehensive analysis using in vitro cellular absorption and skin penetration models has demonstrated that the nanosized pExo carriers significantly improve peptide penetration into the skin compared to free peptides. Furthermore, in vivo tissue slice studies have shown that pExo carriers efficiently deliver acetyl hexapeptide-8 to the skin's dermis, surpassing the performance of free peptides. Cosmetic skincare effect analysis has also indicated that pExo-loaded cosmetic peptides deliver superior results. Therefore, the NanoGlow technique harnesses the natural size and properties of pExo to maximize the bioavailability of cosmetic peptides, holding great promise for developing advanced peptide delivery systems in both the cosmetic and medical drug industries.

Ionic Liquid Pretreatment Enhances Skin Penetration of 5-Aminolevulinic Acid: A Promising Scheme for Photodynamic Therapy for Acne Vulgaris.

Acne vulgaris is one of the most prevalent skin disorders; it affects up to 85% of adolescents and often persists into adulthood. Topical 5-aminolevulinic acid (ALA)-based photodynamic therapy (PDT) provides an alternative treatment for acne; however, its efficacy is greatly undermined by the limited skin permeability of ALA. Herein, biocompatible ionic liquids (ILs) based on aliphatic acid/choline were employed to enhance the dermal delivery of ALA, thereby improving the efficacy of PDT. In addition to the one-step delivery of ALA by utilizing ILs as carriers, a two-step strategy of pretreating the skin with blank ILs, followed by the administration of free ALA, was employed to test the IL-facilitated dermal delivery of ALA in vitro. The cumulative permeation of ALA through the excised rat skin after IL pretreatment was significantly greater than that in the untreated group, the 20% dimethyl sulfoxide (DMSO) penetration enhancer group, and the one-step group. The penetration efficiency was influenced by formulation and treatment factors, including the type of IL, pretreatment duration, water content in the ILs, and concentration of ALA. In rats, IL pretreatment facilitated faster, greater, and deeper ALA-induced protoporphyrin IX (PpIX) accumulation. Moreover, the IL pretreatment regimen significantly improved the efficacy of ALA-based PDT against acne vulgaris in a rat ear model. The model IL choline citrate ([Ch]3[Cit]1) had a moderate effect on the skin barrier. Trans-epidermal water loss could be recovered 1 h after IL treatment, but no irritation to the rat skin was detected after 7 days of consecutive treatment. It was concluded that biocompatible IL pretreatment enhances the penetration of ALA and thus facilitates the transformation of PpIX and improves the efficacy of PDT against acne vulgaris.