Salma Begum, Dr T. Mamatha, Rubina Kauser, Farhana Shaheen, Airaj Mahajabeen
MRM College of Pharmacy, Chintapalliguda, Ibrahimpatnam, R.R District-501510
A B S T R A C T
Isradipine (ISDP) is an effective calcium channel blocker used in the treatment of hypertension. It undergoes extensive first pass metabolism and bioavailability through the oral route is only about 15 to 24%.The purpose of the present study was to formulate and evaluate the microemulsion based transdermal therapeutic system for isradipine (ISDP). Pseudo ternary phase diagrams were constructed to determine the region of existence of microemulsions prepared using phase titration method. The formulations were developed using isopropyl myristate, tween 80 and PEG 400. Optimization of formulations was done based on solubility studies. The microemulsion was gelled using carbopol 934 as the gelling agent. The formulations were evaluated for percent drug content, pH, particle size, zeta potential, polydispersity index, conductivity, viscosity, percent transmittance, in vitro and ex vivo diffusion studies. The formulations B1 and B2 exhibited satisfactory physicochemical characteristics. The cumulative amount of isradipine permeated after 24 h was found to be 4270.11±59.85 μg/hr/cm2. The calculated flux for ISDP was found to be higher than the target flux based on which it can be further evaluated for pharmacokinetic and pharmacodynamic studies.
Keywords: Isradipine, carbopol 934, microemulsion