Hydrogel-thickened nanoemulsions based on essential oils for topical delivery of psoralen: Permeation and stability studies

Design and development of multibiocomponent hybrid alginate hydrogels and lipid nanodispersion as new materials for medical and cosmetic applications

The multibiocomponent hybrid alginate hydrogels based on brown and sea algae, containing 100 % ingredients of natural origin were prepared by ionic crosslinking reaction of a polymeric matrix with lipid nanodispersion. To the best of the Authors' knowledge such multicomponent biobased hydrogel of promising medical and cosmetical applications for the first time was obtained in the environment of flower water, received earlier as a waste by-product from various chemical processes. An innovative hybrid alginate hydrogel that is completely biodegradable and eco-friendly was obtained following waterless and upcycling trends that are in line with the principles of sustainable development. The optimal composition of the lipid nanodispersion and the polymeric matrix was selected using the statistical method of design of the experiment. Based on obtained results, multibiocomponent hybrid alginate hydrogels with various ratios of lipid nanodispersion were obtained. Subsequently, the porous structure and elasticity of the hybrid hydrogels were analyzed. Moreover, to confirm the safety of the multibiocomponent alginate hybrid hydrogels the cytotoxic tests were carried out using human fibroblasts and keratinocytes cell lines. As the final product hybrid of hydrolate-swollen alginate hydrogel and lipid nanodispersion containing several active ingredients (silymarin, bakuchiol, spirulina) was obtained.

Effective Mosquito Repellents: Myrcene- and Cymene-Loaded Nanohydrogels against Aedes aegypti

Aedes mosquito-borne diseases remain a significant global health threat, necessitating effective control strategies. This study introduces monoterpenes-based nanohydrogels for potential use as repellents against Aedes aegypti, the primary dengue vector worldwide. We formulated hydrogels using cymene- and myrcene-based nanoemulsions with different polymers: chitosan, carboxymethylcellulose (CMC), and carbopol®. Our evaluations of rheological, texture, and bioadhesive properties identified CMC hydrogel as the most promising gelling agent for topical application, exhibiting sustained monoterpene release over 12 h with low skin permeation and high retention in the stratum corneum. Myrcene-loaded CMC hydrogel achieved a 57% feeding deterrence compared to 47% with cymene hydrogel in the mosquito membrane-feeding model. Molecular docking studies revealed interactions between myrcene and an essential amino acid (Ile116) in the Ae. aegypti odorant-binding protein 22 (AeOBP22), corroborating its higher repellent efficacy. These findings suggest that myrcene-loaded CMC hydrogels offer a promising, minimally invasive strategy for personal protection against Ae. aegypti and warrant further investigation to optimize monoterpene concentrations for vector control.

Essential Oil Components Incorporated Emulsion Hydrogels for Eradicating Dermatophytosis Caused by Pathogenic Fungi Trichophyton mentagrophytes and Microsporum canis

Dermatophytosis is a prevalent fungal infection and public health burden, majorly caused by the attack of zoophilic fungi genera of Trichophyton and Microsporum. Among them, T. mentagrophytes and M. canis are the dominating pathogens that cause dermatophytosis in humans. Though anti-fungal treatments are available, the widespread drug resistance and minimal efficacy of conventional therapies cause recurring infections. In addition, prolonged anti-fungal medications induce several systemic side effects, including hepatotoxicity and leucopenia. The anti-dermatophytic formulation of biocompatible essential oil components (EOCs) is attractive due to their highly potent anti-dermatophytic action. Herein, two EOCs, Eugenol (EU) and Isoeugenol (IU), incorporated emulsion hydrogel (EOCs-EHG) synthesized from hydroxypropylmethyl cellulose and poly(ethylene glycol) methyl ether methacrylate. The cytocompatibility of the hydrogels is confirmed by treating them with fibroblast and keratinocyte cell lines. The EOCs-EHG demonstrated pH and temperature-responsive sustained release of entrapped EOCs and inhibited fungal spore germination. T. mentagrophytes and M. canis biofilms are eradicated at a minimal inhibitory concentration of 2 µg mL-1 each of EU and IU. The in vivo anti-dermatophytic activity of EOCs-EHG is confirmed in dermatophyte-infected Wistar albino rat models. The topical application of EOCs-EHG demonstrated complete infection eradication and facilitated skin regeneration, emphasizing the therapeutic potential of EOCs-EHG against dermatophytosis.

Protium spruceanum Extract Enhances Mupirocin Activity When Combined with Nanoemulsion-Based Hydrogel: A Multi-Target Strategy for Treating Skin and Soft Tissue Infections

The treatment of skin and soft tissue infections (SSTIs) can be challenging due to bacterial resistance, particularly from strains like MRSA and biofilm formation. However, combining conventional antibiotics with natural products shows promise in treating SSTIs. The objective of this study is to develop a nanoemulsion-based hydrogel containing Protium spruceanum extract and mupirocin and evaluate its potential for the treatment of SSTIs. The nanoemulsion was obtained by phase inversion and subsequently characterized. The antibacterial activity was evaluated in vitro against S. aureus MRSA, including the synergism of the combination, changes in membrane permeability using flow cytometry, and the anti-biofilm effect. In addition, the irritative potential was evaluated by the HET-CAM assay. The combination exhibited synergistic antibacterial activity against S. aureus and MRSA due to the extract enhancing membrane permeability. The hydrogel demonstrated suitable physicochemical properties, inhibited biofilm formation, and exhibited low irritation. The formulation was nanometric (176.0 ± 1.656 nm) and monodisperse (polydispersity index 0.286 ± 0.011). It exhibited a controlled release profile at 48 h and high encapsulation efficacy (94.29 ± 4.54% for quercitrin and 94.20 ± 5.44% for mupirocin). Therefore, these findings suggest that the hydrogel developed could be a safe and effective option for treating SSTIs.

Chitosan-Oxidized Pullulan Hydrogels Loaded with Essential Clove Oil: Synthesis, Characterization, Antioxidant and Antimicrobial Properties

Emulsion hydrogels are promising materials for encapsulating and stabilizing high amounts of hydrophobic essential oils in hydrophilic matrices. In this work, clove oil-loaded hydrogels (CS/OP-C) are synthesized by combining covalent and physical cross-linking approaches. First, clove oil (CO) was emulsified and stabilized in a chitosan (CS) solution, which was further hardened by Schiff base covalent cross-linking with oxidized pullulan (OP). Second, the hydrogels were subjected to freeze-thaw cycles and, as a result, the clove oil was stabilized in physically cross-linked polymeric walls. Moreover, due to cryogelation, the obtained hydrogels exhibited sponge-like porous interconnected morphology (160-250 µm). By varying the clove oil content in the starting emulsion and the degree of cross-linking, the hydrogels displayed a high water retention capacity (swelling ratios between 1300 and 2000%), excellent elastic properties with fast shape recovery (20 s) after 70% compression, and controlled in vitro clove oil release in simulated skin conditions for 360 h. Furthermore, the prepared clove oil-loaded hydrogels had a strong scavenging activity of 83% and antibacterial and antifungal properties, showing a bacteriostatic effect after 48 and 72 h against S. aureus and E. coli. Our results recommend the new clove oil-embedded emulsion hydrogels as promising future materials for application as wound dressings.

Chitosan-based films filled with nanoencapsulated essential oil: Physical-chemical characterization and enhanced wound healing activity

The economic burden of chronic wounds, the complexity of the process of tissue repair and the possibility of resistant bacterial infections, have triggered a significant research interest in the application of natural alternative therapies for wound healing. Biomolecules are intrinsically multi-active, as they affect multiple mechanisms involved in tissue repair phenomenon, including immunomodulatory, anti-inflammatory, cell proliferation, extra cellular matrix remodeling and angiogenesis. Chitosan features a unique combination of attributes, including intrinsic hemostatic, antimicrobial, and immunomodulatory properties, that make it an exceptional candidate for wound management, in the development of wound dressings and scaffolds. In this study, we produced nanoemulsions (NE) loaded with SFO, characterized them, and evaluated their tissue repairing properties. Dynamic light scattering (DLS) analysis confirmed the formation of a nanoemulsion with a droplet size of 21.12 ± 2.31 nm and a polydispersity index (PdI) of 0.159, indicating good stability for up to 90 days. To investigate the potential wound healing effects, SFO-loaded NE were applied on male C57BL/6 mice for seven consecutive days, producing a significantly higher wound closure efficiency (p < 0.05) for the group treated with SFO-loaded NE compared to the control group treated with the saline solution. This finding indicates that the SFO-loaded NE exhibits therapeutic properties that effectively promote wound healing in this experimental model. Then, SFO-loaded NE were incorporated into chitosan:polyvinyl alcohol (PVA)-based films. The inclusion of NE into the polymer matrix resulted in increased lipophilicity reflected by the contact angle results, while decreasing moisture absorption, water solubility, and crystallinity. Moreover, FTIR analysis confirmed the formation of new bonds between SFO-NE and the film matrix, which also impacted on porosity properties. Thermal analysis indicated a decrease in the glass transition temperature of the films due to the presence of SFO-NE, suggesting a plasticizing role of NE, confirmed by XRD results, that showed a decrease in the crystallinity of the blend films upon the addition of SFO-NE. AFM images showed no evidence of NE droplet aggregation in the Chitosan:PVA film matrix. Moisture absorption and water content decreased upon incorporation of SFO-loaded NE. Although the inclusion of NE increased hydrophobicity and water contact angle, the values remained within an acceptable range for wound healing applications. Overall, our results emphasize the significant tissue repairing properties of SFO-loaded NE and the potential of Chitosan:PVA films containing nanoencapsulated SFO as effective formulations for wound healing with notable tissue repairing properties.

Eugenol-Based Polymeric Materials-Antibacterial Activity and Applications

Eugenol (4-Allyl-2-methoxy phenol) (EUG) is a plant-derived allyl chain-substituted guaiacol, widely known for its antimicrobial and anesthetic properties, as well as the ability to scavenge reactive oxygen species. It is typically used as a mixture with zinc oxide (ZOE) for the preparation of restorative tooth fillings and treatment of root canal infections. However, the high volatility of this insoluble-in-water component of natural essential oils can be an obstacle to its wider application. Moreover, molecular eugenol can be allergenic and even toxic if taken orally in high doses for long periods of time. Therefore, a growing interest in eugenol loading in polymeric materials (including the encapsulation of molecular eugenol and polymerization of EUG-derived monomers) has been noted recently. Such active macromolecular systems enhance the stability of eugenol action and potentially provide prolonged contact with pathogens without the undesired side effects of free EUG. In this review, we present an overview of methods leading to the formation of macromolecular derivatives of eugenol as well as the latest developments and further perspectives in their pharmacological and antimicrobial applications.

Development of a Nanoemulgel for the Topical Application of Mupirocin

Mupirocin (MUP) is an effective topical antibiotic with poor skin permeability; however, its skin permeability can be improved by a nanoemulsion formulation based on eucalyptus oil or eucalyptol. Despite this improvement, the nanoemulsion has limitations, such as low viscosity, low spreadability, and poor retention on the skin. To overcome these limitations, the aim of this study was to develop a nanoemulgel formulation that would enhance its rheological behaviour and physicochemical properties. The MUP nanoemulgel was prepared by incorporating a preprepared MUP nanoemulsion into Carbopol gel at a concentration of 0.75% in a 1:1 ratio. The nanoemulgel formulations were characterised and evaluated for their physicochemical and mechanical strength properties, rheological behaviour, and in vitro skin permeation and deposition, as well as antibacterial studies. Both nanoemulgels exhibited stability at temperatures of 4 and 25 °C for a period of 3 months. They had a smooth, homogenous, and consistent appearance and displayed non-Newtonian pseudoplastic behaviour, with differences in their viscosity and spreadability. However, both nanoemulgels exhibited lower skin permeability compared to the marketed control. The local accumulation efficiency of MUP from nanoemulgel after 8 h was significantly higher than that of the control, although there was no significant difference after 24 h. Micro-CT scan imaging allowed visualisation of these findings and interpretation of the deposited drug spots within the layers of treated skin. While there were no significant differences in the antibacterial activities between the nanoemulgels and the control, the nanoemulgels demonstrated superiority over the control due to their lower content of MUP. These findings support the potential use of the nanoemulgel for targeting skin lesions where high skin deposition and low permeability are required, such as in the case of topical antibacterial agents.

Recent Advances in Using Natural Antibacterial Additives in Bioactive Wound Dressings

Wound care is a global health issue with a financial burden of up to US $96.8 billion annually in the USA alone. Chronic non-healing wounds which show delayed and incomplete healing are especially problematic. Although there are more than 3000 dressing types in the wound management market, new developments in more efficient wound dressings will require innovative approaches such as embedding antibacterial additives into wound-dressing materials. The lack of novel antibacterial agents and the misuse of current antibiotics have caused an increase in antimicrobial resistance (AMR) which is estimated to cause 10 million deaths by 2050 worldwide. These ongoing challenges clearly indicate an urgent need for developing new antibacterial additives in wound dressings targeting microbial pathogens. Natural products and their derivatives have long been a significant source of pharmaceuticals against AMR. Scrutinising the data of newly approved drugs has identified plants as one of the biggest and most important sources in the development of novel antibacterial drugs. Some of the plant-based antibacterial additives, such as essential oils and plant extracts, have been previously used in wound dressings; however, there is another source of plant-derived antibacterial additives, i.e., those produced by symbiotic endophytic fungi, that show great potential in wound dressing applications. Endophytes represent a novel, natural, and sustainable source of bioactive compounds for therapeutic applications, including as efficient antibacterial additives for chronic wound dressings. This review examines and appraises recent developments in bioactive wound dressings that incorporate natural products as antibacterial agents as well as advances in endophyte research that show great potential in treating chronic wounds.

Evaluating the Skin Interactions and Permeation of Alginate/Fucoidan Hydrogels Per Se and Associated with Different Essential Oils

Marine polysaccharides are recognized for their biological properties and their application in the drug delivery field, favoring hydrogel-forming capacities for cutaneous application towards several dermatological conditions. Essential oils have been widely used in skin, not only for their remarkable biological properties, but also for their capacity to enhance permeation through the skin layers and to confer a pleasant scent to the formulation. In this study, menthol, L-linalool, bergamot oil, and β-pinene were incorporated in alginate/fucoidan hydrogels to evaluate their skin permeation enhancement profile and assess their influence on the skin organization. The combinations of different essential oils with the marine-based fucoidan/alginate hydrogel matrix were characterized, resulting in formulations with pseudoplastic rheological properties favorable for a uniform application in the skin. The ex vivo Franz diffusion permeation assays revealed that calcein loaded in bergamot-alginate/fucoidan hydrogel permeated more than 15 mg out of the initial 75 mg than when in linalool-alginate/fucoidan, alginate/fucoidan or hydrogel without any incorporated oil. Skin calcein retention for menthol- and pinene-alginate/fucoidan hydrogels was 15% higher than in the other conditions. Infrared micro-spectroscopic analysis through synchrotron-based Fourier Transform Infrared Microspectroscopy evidenced a symmetric shift in CH₃ groups towards higher wavenumber, indicating lipids' fluidization and less lateral packing, characterized by a band at 1468 cm^-1, with the bergamot-alginate/fucoidan, which contributes to enhancing skin permeation. The study highlights the effect of the composition in the design of formulations for topical or transdermal delivery systems.

Stability Studies and the In Vitro Leishmanicidal Activity of Hyaluronic Acid-Based Nanoemulsion Containing Pterodon pubescens Benth. Oil

The physicochemical and microbiological stability of a hyaluronic acid-based nanostructured topical delivery system containing P. pubescens fruit oil was evaluated, and the in vitro antileishmanial activity of the nanoemulsion against Leishmania amazonensis and the cytotoxicity on macrophages was investigated. The formulation stored at 5 ± 2 °C, compared with the formulation stored at 30 and 40 ± 2 °C, showed a higher chemical and physical stability during the period analyzed and in the accelerated physical stability study. The formulation stored at 40 °C presented a significant change in droplet diameter, polydispersity index, zeta potential, pH, active compound, and consistency index and was considered unstable. The microbiological stability of the formulations was confirmed. The leishmanicidal activity of the selected system against intracellular amastigotes was significantly superior to that observed for the free oil. However, further research is needed to explore the use of the hyaluronic acid-based nanostructured system containing P. pubescens fruit oil for the treatment of cutaneous leishmaniasis.

Cellulosic textile/clove nanocomposite as an antimicrobial wound dressing: In vitro and in vivo study

Clove (Syzygium aromaticum) is one of the useful herbal medicine to prevent the bacteria infection. This herbal medicine plant shows high antimicrobial, antioxidant, and anti-inflammation activities because the essential oil and extract of this herb contains a rich source of phenolic compounds. The important phenolic compound of the herb is eugenol. In this study, we endeavored to develop the flexible cellulosic textile nanocomposite by dipping the cellulosic textile in a nano emulsion containing clove herbal medicine (32%wt). This nanocomposite was subjected to detail analyzes using Fourier Transform Infrared Spectroscopy (FTIR), field-emission scanning electron microscope (FESEM) and gas chromatography-mass spectrometry (GC-MS). The mean size of this nano emulsion as measured by electron microscopy is between 100 and 300 nm. The presence of eugenol in this nano emulsion has been confirmed by GC-MS. The wound dressing shows high antimicrobial activity against E. coli (3 ± 0.11 mm), P. aeruginosa (2.8 ± 0.06 mm), S. epidemidis (2.9 ± 0.09 mm), and S. aureus (2.6 ± 0.07 mm). This nano composite showed significant improvement in in vivo wound healing and in vitro cellular compatibility. Nearly 85% of the operation wound was healed during14 days. Accordingly, cellulosic textile/clove wound dressing can be a potential candidate for biomedical application and pre-clinical surveys.

Quaternized Chitosan Thiol Hydrogel-Thickened Nanoemulsion: A Multifunctional Platform for Upgrading the Topical Applications of Virgin Olive Oil

(1) Background: Virgin olive oil (VOO) has attracted the attention of many researchers due to its nutritional and medicinal values. However, VOO’s biological applications have been limited due to a lack of precise chemical profiling and approach to increase the physicochemical characteristics, bioactivity, and delivery of its bioactive components; (2) Methods: The current study intended to evaluate the chemical composition of VOO using the GC-MS technique and determine its major components. Furthermore, the effect of incorporating VOO into Tween 80-lecithin nanoemulsion (OONE) and a quaternized trimethyl chitosan-thiol (TMCT) hydrogel-thickened nanoemulsion system (OOHTN) on its physicochemical characteristics and biological potentials will be investigated; (3) Results: The VOO-based NEs’ physicochemical properties (particle size and zeta potential) were steady during storage for four weeks owing to the inclusion of the protective TMCT hydrogel network to OONE. Excessive fine-tuning of olive oil nanoemulsion (OONE) and the TMCT protective network’s persistent positive charge have contributed to the oil’s improved antimicrobial, anti-biofilm, and antioxidant potentials; (4) Conclusions: The Tween 80-lecithin-TMCT nanosystem might provide a unique and multifunctional nanoplatform for efficient topical therapy as well as the transdermal delivery of lipophilic bioactive compounds.

Formulation and Characterization of Chitosan-Decorated Multiple Nanoemulsion for Topical Delivery In Vitro and Ex Vivo

In the present study, chitosan-decorated multiple nanoemulsion (MNE) was formulated using a two-step emulsification process. The formulated multiple nanoemuslion was evaluated physiochemically for its size and zeta potential, surface morphology, creaming and cracking, viscosity and pH. A Franz diffusion cell apparatus was used to carry out in vitro drug-release and permeation studies. The formulated nanoemulsion showed uniform droplet size and zeta potential. The pH and viscosity of the formulated emulsion were in the range of and suitable for topical delivery. The drug contents of the simple nanoemulsion (SNE), the chitosan-decorated nanoemulsion (CNE) and the MNE were 71 ± 2%, 82 ± 2% and 90 ± 2%, respectively. The formulated MNE showed controlled release of itraconazole as compared with that of the SNE and CNE. This was attributed to the chitosan decoration as well as to formulating multiple emulsions. The significant permeation and skin drug retention profile of the MNE were attributed to using the surfactants tween 80 and span 20 and the co-surfactant PEG 400. ATR-FTIR analysis confirmed that the MNE mainly affects the lipids and proteins of the skin, particularly the stratum corneum, which results in significantly higher permeation and retention of the drug. It was concluded that the proposed MNE formulation delivers drug to the target site of the skin and can be therapeutically used for various cutaneous fungal infections.

Polymeric Nanocapsules Containing Fennel Essential Oil: Their Preparation, Physicochemical Characterization, Stability over Time and in Simulated Gastrointestinal Conditions

Plant essential oils, a source of biologically active compounds, represent a promising segment in the pharmaceutical market. However, their volatility, hydrophobicity, poor stability, and low toxicity limit direct use in pharmaceutical-related applications. Nanoencapsulation is a technique that allows overcoming these obstacles by improving bioaccessibility and bioavailability. Nanocapsules (NCs) based on biodegradable and biocompatible poly(ɛ-caprolactone) containing Foeniculum vulgare Mill. essential oil (FEO), known for its biological activities, were successfully prepared by interfacial deposition of the preformed polymer method. The composition of FEO (trans-anethole chemotype) was determined by gas chromatography analyses. The FEO presence inside the NCs was confirmed by nuclear magnetic resonance experiments. The FEO-NCs showed nanometer size (210 nm), low polydispersity index (0.10), negative zeta potential (-15 mV), non-Newtonian rheological behavior, and high efficiency of encapsulation (93%). Moreover, parameters such as FEO-NC particle size, bioactive compound retention, and FEO composition were monitored for 30 days at storage temperatures of 4 and 40 °C, confirming the robustness of the nanosystem. Finally, FEO-NCs were resistant to the simulated gastric digestion and showed an effective bioaccessibility of 29% in simulated intestinal digestion. Based on the results obtained, this FEO-NC nanosystem could find interesting applications in the nutraceutical and pharmaceutical sectors.

Insightful exploring of advanced nanocarriers for the topical/transdermal treatment of skin diseases

Dermatological products constitute a big segment of the pharmaceutical market. From conventional products to more advanced ones, a wide variety of dosage forms have been developed till current date. A representative of the advanced delivery means is carrier-based systems, which can load large number of drugs for treatment of dermatological diseases, or simply for cosmeceutical purposes. To make them more favorable for topical delivery, further incorporation of these carriers in a topical vehicle, such as gels or creams is made. Therefore in this review article, an overview is compiled of the most commonly encountered novel carrier based topical delivery systems; namely lipid based (nanoemulsions, microemulsions, solid lipid nanoparticles [SLNs] and nanostructured lipid carriers [NLCs]), and vesicular carriers (non-deformable, such as liposomes, niosomes, emulsomes and cerosomes, and deformable, such as transfersomes, ethosomes, transethosomes, and penetration enhancer vesicles), with special emphasis on those loaded in a secondary gel vehicle. A special focus was made on the commonly encountered dermatological diseases, such as bacterial and fungal infections, psoriasis, dermatitis, eczema, vitiligo, oxidative damage, aging, alopecia, and skin cancer.

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 of Propolis (Apis trigona)-loaded Nanoemulgel for Improved Skin Penetration of Caffeic Acid: The Effect of Variation of Oleic Acid Concentration

BACKGROUND: Propolis contains caffeic acid compounds, which are proven to have pharmacological effects as an anti-inflammatory. However, its effectiveness is hampered by the poor solubility of caffeic acid. Here, we report developing the nanoemulgel approach containing propolis extract as an active ingredient and oleic acid as a permeation enhancer for transdermal delivery of caffeic acid. AIM: This study aims to determine the effect of oleic acid concentration on increasing caffeic acid permeation in the skin and obtain a nanoemulgel formula with desired physical characteristics and stability. MATERIALS AND METHODS: Propolis was macerated with 70% ethanol; the total phenolic content was measured by ultraviolet–visible spectrophotometer, and the levels of caffeic acid in the extracts and nanoemulgel preparations were finally determined using ultra-fast liquid chromatography. Formulas were made using various concentrations of oleic acid, namely, 1.25%w/w (Formula F1); 2.5%w/w (Formula F2); 5%w/w (Formula F3), respectively; and 1.25%w/w without propolis extract (Formula F4) as a comparison. RESULTS: The results obtained from analysis of variance statistical exhibited that the difference in oleic acid concentrations in four formulas significantly affected (p < 0.05) particle size, polydispersity index, spreadability, adhesion, freeze-thaw, permeation, and retention test. However, there was no significant difference (p > 0.05) on pH and viscosity before and after 4 weeks of storage and zeta potential test. The highest amount of permeation and retention was found in F3 and F2, respectively, and all formulas tended to follow zero-order drug release kinetics. Furthermore, the results showed that the number of percent’s permeated in a row was 3.74% (F1); 5.58% (F2); 11.67% (F3), and F2 was the formula with the most optimal retention amount with a percentage of 43.13% at 24 h. CONCLUSION: This study shows a promising delivery system for increasing the effectiveness of natural lipophilic compounds to treat inflammation in the skin.

Novel archetype in psoriasis management bridging molecular dynamics in exploring novel therapies

Psoriasis is an autoimmune chronic inflammatory condition of skin affecting 125 million populaces around the globe. It is implicated as a result of multifaceted phenomena involving various cell and subcell activities with the aid of numerous cellular and molecular components including signaling aisle and regulatory proteins owing to the development of such hyperproliferative dermatological conditions. This involves a deeply complex and conflicting pathology owing to genetic and immunological deviations resulting from the unusual presentation of different signaling pathways and regulatory proteins. Explorations of these biomarkers and intervention of molecular and cellular processes in psoriasis are yet to be investigated and could be an exceptional aspect for understanding pathology with successful targeting of disease. In the presented study, we have integrated molecular insights, including signaling molecules, pathways, and proteins implicated in pathogenesis, and we have attempted to link this knowledge to the targeting of these phenomena in order to manage the conditions precisely. Further, therapeutic delivery approaches for targeting distinct layers of skin have also been investigated based on the application of different nanocarriers for successful psoriasis treatment.

Nanoemulsification Improves the Pharmaceutical Properties and Bioactivities of Niaouli Essential Oil (Melaleuca quinquenervia L.)

We develop a suitable delivery system for niaouli essential oil (NEO) using a nanoemulsification method for acne vulgaris. Prepared nanoemulsions (NEs) were characterized for droplet dimension, rheology, surface charge, and stability. The ability of NEO formulations against Propionibacterium acnes and Staphylococcus epidermidis was investigated and all formulations showed antiacne potential in vitro. Ex vivo permeation studies indicated significant improvement in drug permeations and steady state flux of all NEO-NEs compared to the neat NEO (p < 0.05). On the basis of the studied pharmaceutical parameters, enhanced ex vivo skin permeation, and marked effect on acne pathogens, formulation NEO-NE4 was found to be the best (oil (NEO; 10% v/v); Kolliphor EL (9.25% v/v), Carbitol (27.75% v/v), and water (53% v/v)). Concisely, the in vitro and ex vivo results revealed that nanoemulsification improved the delivery as well as bioactivities of NEO significantly.

Nanoliposomes@Transcutol for In Vitro Skin Delivery of 8-Methoxypsoralen

8-methoxypsoralen is the most common drug in psoralen plus ultraviolet light irradiation therapy for the treatment of severe psoriasis. Despite of the efficacy, its classic oral administration leads to several serious adverse effects. However, the topical psoralen application produces a drug skin accumulation lower than that obtained by oral administration, due to the drug low skin permeability. In this paper, 8-methoxypsoralen loaded Penetration Enhancer-containing Vesicles were prepared using soy phosphatidylcholine and the penetration enhancer Transcutol® (5% or 10%) and characterized in terms of size, polydispersity index, zeta potential and encapsulation efficiency. No statistically significant differences in both size (~135 nm) and encapsulation efficiency (~65%) were found for different Transcutol® concentration. Transdermal delivery study assessed by Franz diffusion cells, showed that the 8-methoxypsoralen mainly accumulated into the stratum corneum. Moreover, after Penetration Enhancer-containing Vesicles application, the drug recovered in this layer is almost double of that delivered by conventional liposomes, while no significant difference was found from the different Transcutol® concentrations. Finally, biocompatibility checked by an MTT assay, demonstrated that the incubation of human keratinocytes for 24 h with 8-methoxypsoralen loaded Penetration Enhancer-containing Vesicles did not significantly reduce cell viability.

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.

Recent Advances in the Structural Design of Photosensitive Agent Formulations Using "Soft" Colloidal Nanocarriers

The growing demand for effective delivery of photosensitive active compounds has resulted in the development of colloid chemistry and nanotechnology. Recently, many kinds of novel formulations with outstanding pharmaceutical potential have been investigated with an expansion in the design of a wide variety of "soft" nanostructures such as simple or multiple (double) nanoemulsions and lipid formulations. The latter can then be distinguished into vesicular, including liposomes and "smart" vesicles such as transferosomes, niosomes and ethosomes, and non-vesicular nanosystems with solid lipid nanoparticles and nanostructured lipid carriers. Encapsulation of photosensitive agents such as drugs, dyes, photosensitizers or antioxidants can be specifically formulated by the self-assembly of phospholipids or other amphiphilic compounds. They are intended to match unique pharmaceutic and cosmetic requirements and to improve their delivery to the target site via the most common, i.e., transdermal, intravenous or oral administration routes. Numerous surface modifications and functionalization of the nanostructures allow increasing their effectiveness and, consequently, may contribute to the treatment of many diseases, primarily cancer. An increasing article number is evidencing significant advances in applications of the different classes of the photosensitive agents incorporated in the "soft" colloidal nanocarriers that deserved to be highlighted in the present review.

Treatment of Psoriasis: A Comprehensive Review of Entire Therapies

Background:

Psoriasis is an autoimmune disease that ingeminates itself with the repeated proliferation of keratinocytes. It globally strikes a 2-5 % population on an average. Management of psoriasis remains a daunting task with various challenges influencing treatment, such as patient conformity and adherence to therapy, delicate patient profiles, psychological aspects, and skin as a barrier to topical delivery. The first part reviewed pathophysiology, triggering factors, and clinical classification. The second part reviewed all the therapies, such as topical, oral, biological, parenteral therapy, phototherapy, and the phyto-pharmaceuticals.

Methods:

The research data related to the existing and upcoming therapies for psoriasis treatment, several nanocarriers, existing marketed formulations, and detailed description of phytopharmaceuticals with their mechanism.

Results:

Topical therapy is the mainstay treatment option with limited adverse effects. Biological therapy has reformed conventional psoriasis treatment by being more efficacious and has increased patient acceptance due to decreased adverse events. Nanoformulations present an edge over conventional therapy due to improved anti-psoriatic effect and decreased side effects. Phyto-pharmaceuticals act as a complementary and alternative therapy for diminishing psoriasis symptoms.

Conclusion:

A rationalized cost-effective patient compliant therapy is required for effective management and complete cure of psoriasis.

Trends in nanotechnology-based delivery systems for dermal targeting of drugs: an enticing approach to offset psoriasis

INTRODUCTION

Psoriasis is identified as an inflammatory, chronic, auto-immune disease requiring long-term treatment, imposing an unnecessary burden on the patient. A significant impediment for the treatment of dermatological disorders via transdermal route is the inability of drug molecules to cross the stratum corneum (SC), as the larger size of drug molecules inhibits them to pervade into the skin, thus hampering their absorption. Some drugs exhibit systemic side-effects, which curbs patient compliance, resulting in treatment discontinuation.

AREAS COVERED

This review aims to describe the detailed study such as demographic status, molecular factors of psoriasis, treatment with emerging combination therapy and role of nanotechnology tools in the treatment of psoriasis.

EXPERT OPINION

To overcome problems related to the conventional drug delivery system, several nanotechnology-based formulations have been devised to enhance bioavailability, drug permeation and accumulation in the skin. Nano-formulations provide better permeation, targeted delivery and enhanced efficacy, thus gaining enormous popularity for cutaneous disorders. This pervasive review provides an overview of the pathophysiology of the disease, its molecular targets and the available herbal, synthetic and combination treatment modalities. The review also systematizes recent works utilizing nano-carriers to improve the treatment denouement of psoriasis.

Eprinomectin nanoemulgel for transdermal delivery against endoparasites and ectoparasites: preparation, in vitro and in vivo evaluation

Nanoemulgels are composed of O/W nanoemulsion and hydrogels and are considered as ideal carriers for the transdermal drug delivery because these have high affinity to load hydrophobic drugs. The stable formulation of eprinomectin (EPR) is very challenging because of it is high hydrophobic nature. In this work, we have prepared EPR loaded nanoemulgel for the treatment of endo- and ectoparasites. The surface morphology of optimized formulations was characterized by scanning electron microscopy. Additionally, skin permeability and irritation tests were conducted for in vitro safety and in vivo skin retention and pearmeation test of EPR nanoemulgel were conducted for efficacy study. Obtained results indicated that the optimized formulation had good shear-thinning behavior, bioadhesiveness properties, and are nanosized droplets with porous internal structure, which are required for topical application. Furthermore, this formulation has showed good skin permeability in comparison to suspension and has no skin irritating property. Overall, the obtained results proved that nanoemulgel is a promising carrier for transdermal drug delivery and EPR nanoemulgel is a promising formulation for the treatment of endo- and ectoparasites.

Clove oil nanoemulsion showed potent inhibitory effect against Candida spp

Increasing resistance to current fungicides is a clinical problem that leads to the need for new treatment strategies. Clove oil (CO) has already been described as having antifungal action. However, it should not be applied directly to the skin as it may be irritating. One option for CO delivery and suitable topical application would be nanoemulsions (NEs). NEs have advantages such as decreased irritant effects and lower dose use. The purpose of this work was the development of NEs containing CO and in vitro evaluation against Candida albicans and Candida glabrata. The NEs were produced by an ultrasonic processor with different proportions of CO and Pluronic^® F-127. In order to determine the best composition and ultrasound amplitude, an experimental design was performed. For the evaluation, droplet size and polydispersity index (PdI) were used. After the stability study, in vitro activity against C. albicans and C. glabrata was evaluated. NEs selected for the stability study, with diameter <40 nm and PdI <0.2, remained stable for 420 d. Activity against Candida spp. was improved when the CO was nanoemulsified, for it possibly leads to a better interaction between the active and the microorganisms, mainly in C. albicans.

Nanostructuring lipid carriers using Ridolfia segetum (L.) Moris essential oil

The therapeutic potential of essential oils is widely recognized since antiquity, due to their antibacterial, antifungal, anti-inflammatory and immuno-modulatory properties. In particular, their physicochemical characteristics, such as lipophilicity and permeation enhancement effect have sparked attention for the development of innovative lipid nanosystems. The present work aimed at developing a differentiated nanostructured lipid carrier (NLC) based formulation for topical application, using the Ridolfia segetum essential oil (REO), isolated by hydrodistillation from this Portuguese aromatic plant, with a dual key function, as active and simultaneously nanostructuring component of the nanoparticles. The incorporation of the essential oil in the solid lipid matrix, followed by the respective hot high-pressure homogenization, led to particles with a size of 143 ± 5 nm, along with a polydispersity index of 0.21, a zeta potential of -16.3 ± 0.6 mV, encapsulation efficacy of ca. 100% and loading capacity of 1.4%. A comprehensive physicochemical characterization of the lipid nanosystem, including morphology, structural, thermal and accelerated stability analysis confirmed its nanostructured nature. REO-NLC was further jellified for designing an appropriate semisolid topical dosage form. In vitro release, permeation and skin retention studies evidenced a sustained release behaviour and a reservoir-like effect, suitable for a prolonged topical delivery. Cytotoxicity studies, performed in fibroblasts and keratinocytes, revealed the biocompatibility of the developed formulations. This work highlights the critical role of REO as a multiaddressable compound, both as active pharmaceutical ingredient and nanostructuring agent, able to tailor the permeation enhancement profile of nanoparticles towards topical delivery purposes and concomitantly presenting a safety profile for cosmetic and/or pharmaceutical purposes.

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.

Understanding the prospective of nano-formulations towards the treatment of psoriasis

Psoriasis is a consistently recurring, inflammatory, autoimmune disorder of the skin, affecting about 2-5% of the world population. Abundant therapeutic agents are accessible for the treatment of psoriasis. Nevertheless, none of them are entirely secure and effective to treat the disease without compromising patient compliance. Furthermore, already existing drugs are supposed to restrain the ailment and alleviate the sign and symptoms with no complete cure. However, they focus on restraining the disease and alleviating the symptoms without providing an absolute cure. Therefore there remains a vital challenge, to explore a new drug moiety or delivery system which could safely and effectively manage psoriasis without compromising patient compliance. Furthermore, conventional formulations offer reduced benefit/risk ratio of anti-psoriatic drugs, which limits the use of existing conventional formulations. Novel formulations based on nanocarriers are a promising prospect to overcome the limitation of conventional formulations by offering a reduction in dose, dosing frequency, dose-dependent, side effects with enhanced efficacy. Presently nano-formulations have gained widespread application for effective and safe treatment of psoriasis. The present review primarily focuses on conventional therapeutic strategy and recent advances in lipid-based, polymer-based and metallic nano-formulations of a variety of anti-psoriatic drugs. The practicability of various nanocarrier systems including liposomes, nanostructured lipid carriers, ethosomes, solid lipid nanoparticles, nanocapsules, micelles, dendrimers, gold nanoparticles and silver nanoparticles have been discussed in detail. The review also traces related patents to exemplify the role of various nanoparticles in psoriasis treatment. In a nutshell, nano-formulations remain established as a promising modality for treating psoriasis treatment as they propose better penetration, targeted delivery, enhanced safety, and efficacy.

Nanoemulsion containing 8-methoxypsoralen for topical treatment of dermatoses: Development, characterization and ex vivo permeation in porcine skin

Oral therapy with 8-methoxypsoralen (8-MOP) may cause major side effects, whereas the topical treatment might not be much effective due to the low penetration induced by typical formulations. Therefore, the objectives of this work are the development and characterization of a nanoemulsion (NE) containing 8-MOP together with an ex vivo permeation study, monitored by a validated HPLC-Fluo method, to determine the amount of drug retained in viable skin (epidermis (E) and dermis (D)) and in stratum corneum (SC). The optimized conditions for NE formulation were achieved by full factorial designs (2⁵ and 3²): 60 s and 60% of ultrasound time and potency, respectively; 10 mL of final volume; 2% v/v of oil phase (clove essential oil); and 10% m/v of Poloxamer 407. The NE showed mean droplet diameter of 24.98 ± 0.49 nm, polydispersity index (PDI) of 0.091 ± 0.23, pH values of 6.54 ± 0.06, refractive index of 1.3525 ± 0.0001 and apparent viscosity of 51.15 ± 3.66 mPa at 20 °C. Droplets with nanospherical diameters were also observed by transmission electron microscopy (TEM). Ex vivo permeation study showed that 8.5% of the applied 8-MOP dose permeated through the biological membranes, with flux (J) of 1.35 μg cm^-2 h^-1. The drug retention in E + D and in SC was 10.15 ± 1.36 and 1.95 ± 0.71 µg cm^-2, respectively. Retention in viable skin induced by the NE was almost two-fold higher than a compounded cream (5.04 ± 0.30 μg cm^-2). These results suggested that the developed NE is a promising alternative for 8-MOP topical therapy when compared to commercial formulations.

Potential Application of Nanoemulsions for Skin Delivery of Pomegranate Peel Polyphenols

Pomegranate peel and seeds have demonstrated to possess antioxidant compounds with potential application to protect the skin against the ultraviolet radiation damage. However, the photoprotection activity is dependent on the amount of these compounds that reach the viable skin layers. In this paper, we describe the in vitro skin permeation and retention of the major pomegranate peel polyphenols using Franz diffusion cells, after entrapping a ethyl acetate fraction (EAF) from Punica granatum peel extract into nanoemulsions (NEs) prepared with pomegranate seed oil (PSO) or medium chain triglyceride oil (MCT). The in vitro skin permeation of gallic acid (GA), ellagic acid (EA), and punicalagin (PC) was evaluated using a HPLC-DAD validated method. After 8 h of skin permeation, all polyphenol compounds were mostly retained in the skin and did not reach the receptor compartment. However, a 2.2-fold enhancement of the retained amount of gallic acid in the stratum corneum was verified after EAF-loaded NEs are applied, when compared with the free EAF. GA and EA were delivered to the viable epidermis and dermis only when nanoemulsions were applied onto the skin. The mean retained amounts of GA and EA in the EP and DE after applying the EAF-loaded PSO-NE were 1.78 and 1.36 μg cm^-2 and 1.10 and 0.97 μg cm^-2, respectively. Similar values were obtained after applying the EAF-loaded MCT-NE. The skin permeation results were supported by the confocal microscopy images. These results evidenced the promising application of nanoemulsions to deliver the pomegranate polyphenols into the deeper skin layers.