This study aimed to develop ultradeformable liposomes (ULs) with fatty acids, namely, oleic, linoleic, and linolenic acid, to improve the skin penetration of rosmarinic acid. This study also investigated the vesicle-skin interaction and skin penetration pathway of ULs with fatty acids using the co-localization technique of multifluorescently labeled particles. The prepared ULs were characterized in terms of size, surface charge, size distribution, shape, % entrapment efficiency (% EE), and % loading efficiency (% LE). The prepared ULs with fatty acids had an average particle size between 50.37 ± 0.3 and 59.82 ± 17.3 nm with a size distribution within an acceptable range and exhibited a negative surface charge. The average % EE and % LE were 9 and 24.02, respectively. The in vitro skin penetration study found that ULs with oleic acid could significantly increase the skin penetration of rosmarinic acid compared to ULs. According to confocal laser scanning microscopy observations, this study suggested that UL vesicles attach to the skin before releasing the entrapped drug to penetrate the skin. These findings suggested that ULs with oleic acid penetrated the skin via the transfollicular pathway as a major penetration pathway.

Purpose: The purpose of this study was to develop a microemulsion containing D-α-tocopheryl polyethylene glycol 1000 succinate (vitamin E TPGS) as a biodegradable surfactant to increase the oral absorption of celecoxib. Methods: This study investigated the intestinal absorption enhancement mechanism of this microemulsion by measuring transepithelial electrical resistance (TEER) values. This study also evaluated microemulsion particle–intestine interactions in terms of release and attachment processes using confocal laser scanning microscopy (CLSM). Results: The prepared microemulsion particles had a size of <300 nm with a neutral surface charge. The celecoxib-loaded microemulsion release kinetic was classified as the zero-order model. This vitamin E TPGS-based microemulsion significantly increased the in vitro intestinal absorption of celecoxib compared to celecoxib solution. The CLSM study suggested that microemulsion particles with entrapped drugs might attach to the intestinal epithelium before releasing the entrapped drug into tissues. The TEER value of the intestinal tissues treated with the celecoxib-loaded microemulsion was significantly decreased compared to the value before treatment, indicating an increase in drug transport via the paracellular pathway. The evaluation of intestinal tissue cytotoxicity using lactate dehydrogenase cytotoxicity assay suggested that the prepared celecoxib-loaded microemulsion was safe for oral route administration. Conclusions: The prepared celecoxib loaded microemulsion could increase the intestinal absorption of celecoxib compared to celecoxib solution. The intestinal absorption enhancement mechanism of this microemulsion resulted from the increase of the drug transport via the paracellular pathway.

This study aimed to investigate the effects of a facial serum containing Tubtim Chumphae rice extract on skin hydration, elasticity, oiliness, pigmentation, and erythema in healthy adults aged 30–50 years. Thirty participants applied two facial serums daily to opposite sides of the face for 12 weeks: (1) a serum containing Tubtim Chumphae rice extract (treatment intervention) and (2) a standard serum formulation containing 2% α-arbutin (control intervention). Skin hydration, elasticity, oiliness, melanin, and erythema were assessed at baseline and after the intervention using non-invasive skin measurement techniques. At baseline, no significant differences were observed between facial sides for any outcome. After 12 weeks, the side treated with the treatment intervention demonstrated significant within-side improvements in skin hydration at the forehead, skin elasticity at the cheeks and chin, and reductions in melanin and erythema in selected facial regions (all p < 0.05). However, paired split-face comparisons revealed that the treatment intervention produced significantly greater skin hydration at the cheek (mean difference = 3.88 AU, 95% CI: 0.23–7.53 AU, p = 0.039) and significantly greater skin elasticity at the forehead (mean difference = 0.090, 95% CI: 0.011–0.169, p = 0.028) compared with the control intervention. In addition, skin oiliness at the cheek was significantly lower on the side treated with the treatment intervention (mean difference = −6.62 µg/cm², 95% CI: −12.62 to −0.62 µg/cm², p = 0.032). No significant between-intervention differences were observed for melanin or erythema at any facial region. These findings suggest that topical application of a facial serum containing Tubtim Chumphae rice extract may improve skin hydration and elasticity while reducing skin oiliness in healthy middle-aged adults. However, no significant advantages over a standard 2% α-arbutin serum were observed for skin pigmentation or erythema after 12 weeks of treatment. Clinical Trial Registration: ClinicalTrials.gov, NCT06475222.

Background/Objectives: The present study aimed to synthesize folate-conjugated poloxamers and develop polymeric micelles for the dermal delivery of irinotecan and alpha-mangostin for the treatment of melanoma using poloxamer 188 and poloxamer 184, which have never been synthesized with folate before. Methods: Poloxamer 188 and poloxamer 184 were synthesized with folate by esterification. The in vitro skin penetration enhancement of irinotecan- and alpha-mangostin-loaded folate-conjugated polymeric micelles was evaluated. The skin penetration pathway of folate-conjugated polymeric micelles was investigated by colocalization of multiple fluorescently labeled particles using confocal laser scanning microscopy (CLSM). Results: Folate-conjugated poloxamer 188 and poloxamer 184 were successfully synthesized. The prepared irinotecan- and alpha-mangostin-loaded folate-conjugated polymeric micelles from poloxamer 188 and poloxamer 184 had particle sizes of approximately 180 and 150 nm, respectively, indicating a positive charge with a narrow size distribution which could be easily taken up into cells. An in vitro skin penetration study revealed that folate-conjugated polymeric micelles from poloxamer 184 significantly enhanced the skin penetration of irinotecan and alpha-mangostin to a greater extent than the solution. CLSM visualization revealed that folate-conjugated polymeric micelles penetrated through the skin by the transfollicular pathway as the major penetration pathway, whereas penetration by the intercluster pathway, transcellular pathway and intercellular pathway constituted a minor pathway. Conclusions: Folate-conjugated poloxamer 184 polymeric micelles are promising candidates for the dermal delivery of anticancer drugs by the transfollicular pathway as the major skin penetration pathway.

This study characterized the in vitro properties of a Hom pathum rice extract and explored the clinical performance of a facial mask containing the extract. In this single-center, assessor-blinded, two-arm randomized controlled trial, 60 patch-test-negative healthy adults aged 30–50 years were allocated 1:1 to a no-treatment control group or to a treatment group that applied a multi-ingredient facial mask containing 0.27% (w/w) Hom pathum rice extract for 30 min twice weekly for 12 weeks. Hydration, elasticity, oiliness, melanin, and erythema were assessed at the forehead, cheek, and chin. Complete-case week-12 comparisons used ANCOVA adjusted for the corresponding baseline value, age, and sex, followed by Benjamini–Hochberg correction across the 15 between-group comparisons. Forty-nine participants completed follow-up (control, 24; treatment, 25). The ethanolic extract showed 55% DPPH radical-scavenging activity, an IC₅₀ of 2.29 ± 0.02 mg/mL, and a total phenolic content of 0.01 ± 0.00 mg GAE/mg extract; total flavonoids were below the assay detection limit at 5 mg/mL. Six comparisons were nominally significant, of which three remained significant after false-discovery-rate correction: higher forehead hydration (adjusted mean difference, 9.42 AU; 95% CI, 2.79 to 16.06; p = 0.007; q = 0.033), lower chin oiliness (−33.15 μg/cm²; 95% CI, −52.40 to −13.89; p = 0.001; q = 0.022), and lower cheek melanin (−68.65 AU; 95% CI, −112.89 to −24.41; p = 0.003; q = 0.026). However, none of the 15 comparisons reached nominal or FDR-adjusted significance in the intention-to-treat multiple-imputation sensitivity analysis (all p ≥ 0.092). No intervention-related adverse effects were recorded among the enrolled patch-test-negative participants. These findings apply to the formulation and application procedure as a whole and were not statistically confirmed in the intention-to-treat sensitivity analysis; they therefore warrant confirmation in an adequately powered, double-blind, vehicle-controlled trial with a prespecified primary outcome. ClinicalTrials.gov: NCT06475222. Funding: Burapha University, Thailand Science Research and Innovation, and the National Science Research and Innovation Fund.