title: Evaluation of nicotinamide microemulsion on the skin penetration enhancement.
abstract: This study purposed to evaluate a microemulsion containing nicotinamide for its characteristics, stability, and skin penetration and retention comparing with a solution of nicotinamide in 2:1 mixture of water and isopropyl alcohol (IPA). The microemulsion system was composed of 1:1 mixture of Span80 and Tween80 as a surfactant mixture, isopropyl palmitate (IPP) as an oil phase, and 2:1 mixture of water and IPA as an aqueous phase. Nicotinamide microemulsion was prepared by dissolving the active in the aqueous phase before simply mixing with the other components. It was determined for its characteristics and stability under various conditions. The skin penetration and retention studies of nicotinamide microemulsion and solution were performed by modified Franz diffusion cells, using newborn pig skin as the membrane. The results showed that nicotinamide microemulsion could be obtained as clear yellowish liquid, was water-in-oil (w/o) type, possessed Newtonian flow, and exhibited physicochemical stability when kept at 4 °C and room temperature (≈30 ± 2 °C) during 3 months. From the skin penetration data, the microemulsion could enhance the skin penetration of nicotinamide comparing with the solution. Additionally, nicotinamide microemulsion could provide much higher amount of skin retention than that of skin penetration, resulting in suitability for a cosmeceutical product.
authors.affiliation: a Department of Pharmaceutical Technology, Faculty of Pharmaceutical Sciences , Prince of Songkla University , Songkhla , Thailand and.|b Faculty of Pharmaceutical Sciences, Nanotec-PSU Center of Excellence on Drug Delivery System , Prince of Songkla University , Songkhla , Thailand.
authors.forename: Prapaporn
authors.initials: P
authors.lastname: Boonme
authors.affiliation: a Department of Pharmaceutical Technology, Faculty of Pharmaceutical Sciences , Prince of Songkla University , Songkhla , Thailand and.|b Faculty of Pharmaceutical Sciences, Nanotec-PSU Center of Excellence on Drug Delivery System , Prince of Songkla University , Songkhla , Thailand.
authors.forename: Chalida
authors.initials: C
authors.lastname: Boonthongchuay
authors.affiliation: a Department of Pharmaceutical Technology, Faculty of Pharmaceutical Sciences , Prince of Songkla University , Songkhla , Thailand and.
authors.forename: Wibul
authors.initials: W
authors.lastname: Wongpoowarak
authors.affiliation: a Department of Pharmaceutical Technology, Faculty of Pharmaceutical Sciences , Prince of Songkla University , Songkhla , Thailand and.
authors.forename: Thanaporn
authors.initials: T
authors.lastname: Amnuaikit
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D000831:Animals, Newborn; D004353:Drug Evaluation, Preclinical / Q000379:methods; D004655:Emulsions / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics*; D009536:Niacinamide / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics*; D009924:Organ Culture Techniques; D012869:Skin Absorption / Q000187:drug effects* / Q000502:physiology; D013552:Swine; D014783:Viscosity
chemical_list: D004655:Emulsions; D009536:Niacinamide
keywords: Microemulsion; nicotinamide; skin penetration; skin retention