ABSTRACT
BACKGROUND: Horse oil (HO) has skin barrier restoration and skin-moisturizing effects. Although cream formulations have been used widely and safely, their limited penetration through the stratum corneum is a major obstacle to maximizing the cosmetic efficacy of HO. Therefore, we aimed to encapsulate HO in a cosmetic dissolving microneedle (DMN) for efficient transdermal delivery. METHODS: To overcome these limitations of skin permeation, HO-loaded DMN (HO-DMN) patches were developed and evaluated for their efficacy and safety using in vitro and clinical studies. RESULTS: Despite the lipophilic nature of HO, the HO-DMN patches had a sharp shape and uniform array, with an average length and tip diameter of 388.36 ± 16.73 and 38.54 ± 5.29 µm, respectively. The mechanical strength of the HO-DMN patches was sufficient (fracture force of 0.29 ± 0.01 N), and they could successfully penetrate pig skin. During the 4-week clinical evaluation, HO-DMN patches caused significant improvements in skin and dermal density, skin elasticity, and moisturization. Additionally, a brief safety assessment showed that the HO-DMN patches induced negligible adverse events. CONCLUSION: The HO-DMNs are efficient, safe, and convenient for wide use in cosmetic applications for skin barrier restoration and moisturization.
Subject(s)
Lubricants/administration & dosage , Oils/administration & dosage , Skin Absorption , Skin/drug effects , Administration, Cutaneous , Adult , Animals , Cosmetics/administration & dosage , Cosmetics/isolation & purification , Cosmetics/pharmacokinetics , Drug Delivery Systems , Elasticity/drug effects , Female , Horses , Humans , Lubricants/isolation & purification , Lubricants/pharmacokinetics , Middle Aged , Needles , Oils/isolation & purification , Oils/pharmacokinetics , Skin/metabolism , Swine , Transdermal PatchABSTRACT
BACKGROUND: Dissolving microneedles (DMNs) have been used for skin restoration and wrinkle improvement. Although lipophilic compounds, for example, natural oils or ceramides, enrich the skin barrier, their delivery via DMNs is challenging because of DMN fabrication difficulties. OBJECTIVES: In the present study, we combined a topical formulation and a DMN patch to perform two-phase delivery comprising a lipophilic formulation and hydrophilic compound-loaded DMNs to improve skin barrier status and the efficacy of drug delivery. METHODS: Horse oil-spread and adenosine-loaded DMN arrays were developed in a single patch (HOS-Ad-DMN patch). In vitro analysis was conducted to confirm the successful delivery of the compositions. Clinical assessments were conducted on the lateral canthus of 20 women to compare the efficacy of HOS-Ad-DMN patches with that of adenosine-loaded DMN patches (Ad-DMN patches). RESULTS: Adenosine was delivered via the DMNs after skin penetration and horse oil was delivered successfully into the skin through the microchannels created by the Ad-DMNs. Compared with Ad-DMN patches, HOS-Ad-DMN patches significantly improved skin elasticity, hydration, dermal density, and wrinkles. No adverse events were observed. CONCLUSION: HOS-Ad-DMN patches are a safe and efficient system for skin restoration and wrinkle improvement.