title: Basil oil is a promising skin penetration enhancer for transdermal delivery of labetolol hydrochloride.
abstract: The present work investigates effectiveness of basil oil, a volatile oil containing alcoholic terpenes, as a potential penetration enhancer for improved skin permeation of labetolol hydrochloride (LHCl) with reference to camphor, geraniol, thymol, and clove oil. Saturation solubilities of LHCl were determined in water, vehicle (ethanol:water, 60:40 v/v) and vehicle containing 5% w/v terpenes. Comparable (P > 0.05) saturation solubilities were found suggesting an insignificant increase in LHCl flux across rat skin on account of thermodynamic activity. Permeation of LHCl in vehicle per se and in presence of 5% w/v enhancer was investigated by performing in vitro rat abdominal skin permeation studies using a side-by-side glass diffusion cell. Various parameters viz. steady state flux, permeability coefficient, lag time, partition coefficient, diffusion coefficient, and enhancement ratios (ER) were calculated from the permeation data. Basil oil produced the maximum enhancement (ER = 46.52) over neat vehicle, among all enhancers. Activation energies for LHCl permeation in water, vehicle per se and in presence of 5% w/v basil oil were found to be 23.16, 18.71, and 10.98 kcal/mole, respectively. Lowering of activation energy in presence of basil oil suggests creation of new polar pathways in the skin for enhanced permeation of LHCl. Basil oil is proposed as a promising penetration enhancer for improved transdermal drug delivery of labetolol.
authors.affiliation: Department of Pharmaceutics, Faculty of Pharmacy, Hamdard University, M.B Road, New Delhi, India.
authors.forename: Rahul
authors.initials: R
authors.lastname: Jain
authors.forename: Mohammed
authors.initials: M
authors.lastname: Aqil
authors.forename: Abdul
authors.initials: A
authors.lastname: Ahad
authors.forename: Asgar
authors.initials: A
authors.lastname: Ali
authors.forename: Roop K
authors.initials: RK
authors.lastname: Khar
mesh_terms: D000080462:Acyclic Monoterpenes; D000818:Animals; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000493:pharmacokinetics*; D002164:Camphor / Q000737:chemistry; D045783:Clove Oil / Q000737:chemistry; D005079:Excipients / Q000737:chemistry*; D066298:In Vitro Techniques; D007741:Labetalol / Q000008:administration & dosage / Q000493:pharmacokinetics*; D008297:Male; D031339:Ocimum; D010539:Permeability; D010938:Plant Oils / Q000737:chemistry*; D051381:Rats; D017208:Rats, Wistar; D012869:Skin Absorption; D013729:Terpenes / Q000737:chemistry; D013816:Thermodynamics; D013943:Thymol / Q000737:chemistry
chemical_list: D000080462:Acyclic Monoterpenes; D000959:Antihypertensive Agents; D045783:Clove Oil; D005079:Excipients; D010938:Plant Oils; D013729:Terpenes; D013943:Thymol; D002164:Camphor; C007836:geraniol; D007741:Labetalol; C051168:basil oil