The present work is designed to achieve efficient localized skin delivery of folic acid (FA) loaded nanostructured lipid carriers (NLCs) to infer efficient treatment of skin photoaging conditions induced via excessive exposure to ultraviolet (UV) radiation. FA NLCs were prepared by high speed homogenization followed by ultrasonication. The obtained NLCs revealed high encapsulation efficiencies (89.42–99.26%) with nanometric particle sizes (27.06-85.36 nm) of monodisperse distribution (PDI =0.137–0.442), zeta potential values > |27| mV, pseudoplastic rheological behavior, good spreadability (2.25-3.30 cm) and promoted occlusive properties throughout 48 h. Optimized NLC formulations appeared as sphere-shaped particles using transmission electron microscopy, showed improved photostability of FA and prolonged in vitro release profile best fitted to Higuchi diffusion model. Ex vivo permeation and deposition of FA, employing Wistar rat skins, depicted enhanced permeability and existence of FA in skin layers after 6 h. Based on the obtained results, FA loaded NLC formulations demonstrate a promising modality for anti-photoaging therapy.

The rising incidence of vulvovaginal candidiasis (VVC) has been leading to the development of alternative antifungal therapies. This study aimed to develop a topical chitosan–oleic acid nanoparticle (CH-OA-NP) cream loaded with lemon peel essential oil (LPEO) for VVC treatment. The characterization of the optimal nanoparticle formulation (F4: 10 g/L CH, 2:1 OA/LPEO ratio) showed high encapsulation efficiency, stability, and controlled release. Moreover, it was characterized regarding its particle size, polydispersity index, zeta potential, and chemical/morphological profile. LPEO-related compounds (e.g., eriodictyol) were identified through LC-ESI-QqTOF-HRMS in the cream matrix, suggesting the preservation of LPEO potential bioactivities after formulation. In silico docking of 12 LPEO metabolites revealed that compounds such as citronellic acid exerted inhibitory effects against several inflammation-associated enzymes (e.g., 14-α-Demethylase). In vitro antimicrobial tests demonstrated remarkable activity against Candida albicans, Gram-negative (e.g., Escherichia coli), and Gram-positive (e.g., Staphylococcus aureus) bacteria. In vivo studies in a rat model of VVC revealed significant antifungal, anti-inflammatory, and immunomodulatory effects of the LPEO-CH-OA-NP cream (5% and 10%), leading to reduced MDA, MPO, and IL-1β levels and increased GSH activity. This novel formulation potentially offers a promising alternative therapy for VVC, addressing the current antifungal therapies’ limitations, counteracting drug resistance.

Purpose: The current study aims to improve the oral bioavailability of Origanum majorana essential oil loaded nanoemulsions (OMEO -NEs) for the treatment of Alzheimer’s disease in mice induced by lipopolysaccharide (LPS). Methods: Gas Chromatography–Mass Spectrometry analysis (GC–MS) analyses were performed to determine the Origanum majorana leaves essential components. Yield essential oil, phenolic content, and flavonoid content were also ascertained. Four NEs containing various concentrations of carboxy methyl cellulose (CMC) and a fixed concentration of Tween 80 as mixed emulsifiers. Plain OMEO and its chosen NE were tested for their antioxidant properties against DPPH & ABTS, hydrogen peroxide, and metal chelation assay. The mice in the in vivo study were divided into five groups at random (8 per group): Group 1: normal control group. Group 2: LPS positive group (250 µg/kg; intraperitoneal); Groups 3–5: Oral administration of 400 mg/kg of Blank NE, plain OMEO, and OMEO-NE for 7 days in conjunction with LPS. Results: GC–MS identified the primary constituents which are α-Terpineol (21.85%), γ-Terpinene (12.43), and α-Caryophyllene (11.78%). The encapsulation efficiency % of NE was improved when the concentration of CMC was reduced. Particle size and zeta potential values in the prepared NE were reasonable. In every test, the chosen OMEO-NE showed stronger antioxidant activity than plain OMEO. When compared to LPS-treated mice, OMEO-NE increased cognitive function and decreased AChE, TLR4, and GFAP levels. Conclusion: The current study provides opportunities for safer approaches that using compounds derived from plants and links it to nanotechnology, could be used in the pharmaceutical industry to treat Alzheimer’s disease.

Recently, hand sanitization has gained attention for preventing disease transmission. Many on-the-market convenient dermal sanitizers contain alcohol, which can be detrimental to the skin. Therefore, three nanoemulgel formulations (LN-F1, LN-F2, LN-F3) incorporating lemon peel extract (LE), and with various increasing concentrations of xanthan gum as a gelling agent and stabilizer, were developed and characterized as a novel alternative. All formulations showed non-Newtonian shear-thinning flow behavior, particle size values below 200 nm, and increasing zeta potential with higher xanthan gum concentrations. All nanoemulgel formulations exhibited greater in vitro phenolic compound release than free LE. LN-F2 (1.0% LE, 20.0% mineral oil, 20.0% Span 80, 4.0% Cremophor RH 40, 4.0% PEG 400, 0.5% xanthan gum, 50.5% dH₂O) was selected as the optimal formulation due to improved characteristics. LE and LN-F2 potential cytotoxicity was assessed on MA-104, showing no significant cellular morphological alterations up to 10 mg/mL for both samples. LN-F2 showed in vitro antimicrobial activity against E. coli, S. Typhimurium, P. aeruginosa, S. aureus, L. monocytogenes, and C. albicans, as well as antiviral activity against phiX 174, but no effect against rotavirus (SA-11). In vivo, LN-F2 presented a removal capacity of 83% to 100% for bacteria and 89% to 100% for fungi. These findings suggest that the formulated nanoemulgel holds potential as a safe and effective antiseptic, providing a viable alternative to commercial alcohol-based formulations.

The aim of this review is to highlight the role of semisolid systems as vehicles for nanovesicles and nanoparticles. In general, nanotechnology plays a critical role in facilitating the delivery of therapeutic agents to their active sites, and several nanocarrier systems have been explored for the topical administration of active components. The major disadvantage of the prepared nanosystems is their low viscosity, which reduces the time needed for enough absorption and negatively affects their stability and bioavailability. The role of semisolid systems is to overcome this limitation. In conclusion, this review presents an updated summary of recent advances in the use of semisolids as vehicles for various nanosystems through comprehensive scrutiny of the types of semisolids and their advantages and their role in enhancing the absorption of nanoparticles and nanovesicles.