Research Article Volume 23 Issue 2 (2012) 121 Indonesian J. Pharm. Vol. 23 No. 2 : 121 – 129 ISSN-p : 0126-1037 PASSIVE AND IONTOPHORETIC PERMEATION OF CAPTOPRIL GEL: AN IN VITRO AND IN VIVO STUDY Ashish Jain 1 *, Satish Nayak 1 , Vandana Soni 2 1 Bansal College of Pharmacy, Kokta, Anand Nagar, Bhopal-462021, India. 2 Department of Pharmaceutical Sciences, Dr H.S.Gour Vishwavidyalaya, Sagar 470003, M.P. India Submitted: 24-05-2012 Revised: 10-06-2012 Accepted: 20-06-2012 *Corresponding author. Ashish Jain Email : aashish.pharmatech@gmail.com ABSTRACT The Objective of this work was to formulate and evaluate captopril gel to assess its suitability for transdermal delivery by passive and iontophoresis. A polymer gel was prepared using hydroxypropyl methyl cellulose and in vitro skin permeability was assessed in full thickness skin of rabbits and pigs. For in vivo studies New Zealand rabbits were used. In vitro passive permeation was carried out in Franz diffusion cell but for iontophoresis, diffusion cell was modified according to Glikfield design. Iontophoresis was performed at a current density of 0.5 mA/cm 2 via silver /silver chloride electrodes with passive controls but for in vivo study current density was reduced to 0.1 mA/cm2. Blood samples were analyzed for drug content by HPLC. Results of the in vitro study indicated that iontophoresis considerably increased the permeation rate of captopril compared to passive controls in both the skin types (P<0.01). The plasma concentration of captopril was significantly higher (P<0.001) than that obtained in the passive controls. Results showed that the target permeation rates for captopril could be achieved with the aid of iontophoresis by increasing the area in an appreciable range. Key words: Captopril, iontophoresis, transdermal, Rabbit, Pigskin, in vitro, in vivo. INTRODUCTION If we analyze the history of human suffering, we observe that diseases and compulsions imposed by diseased states are considered to be a greater enemy to mankind rather than the death. Naturally, the ultimate aim of every therapy is to restore the normalcy of life, but ironically sometimes, the requirements of treatment are such that the normal rhythm of life is disturbed. Today most of drugs are taken orally and are found not to be as effective as desired. To improve such characters transdermal drug delivery system was emerged. To achieve and maintain drug concentration above the minimum therapeutic level it is the need of transdermal system to overcome the barrier properties of skin. Iontophoresis is a form of transdermal delivery that use in electric field to enhances the movement of small, poorly absorbed ionic drug across the skin in controlled and program- mable manner (Nair and Panchagnula, 2003; Kalia et al., 2004; Zakzewski et al., 1992). The enhancement of drug due to this method results from a number of possible mechanisms including the ion-electric field interaction (electro repulsion), convective flow (electro- osmosis) and current-induced (Wang et al., 2004; Pillai et al., 2004) increase in skin permeability. Captopril is an oral drug and a member of a class of drugs called angiotensin converting enzyme (ACE) inhibitors. ACE inhibitors are used for treating high blood pressure, heart failure, and for preventing kidney failure due to high blood pressure and diabetes. It has a short elimination half life and its plasma half life in man ranges from 1.6-1.9 hour (Jarrott et al., 1982; Raia et al., 1990; Levy et al., 1990). Moreover food may decrease oral absorption of captopril by up to 25-40% (Ohman et al., 1985; McEvoy 1996). The main problems associated with oral therapy include uneven bio-distribution throughout the body, a lack of drug targeting specificity, the necessity of a large dose to achieve high blood concentration and adverse side effects due to such high doses