Spectrophotometric determination of heparin using phenosafranine and its application

College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao, 266042, People's Republic of China E-mail: sunwei_1975@public.qd.sd.cn Manuscript received 27 December 2005, revised 25 April 2006, accepted 17 May 2006 Based on the binding interaction of heparin with phcnosafranine (PSF), a new spectrophotometric method for the determination of heparin, which Is a pharmaceutical products, was described in this paper. At pH 1.5 Britton- Robinson (B-R) buffer solution the binding reaction was completed within 10 min at room temperature, resulting in the absorbance decrease at maximum wavelength or PSF at 532 nm. The calibration curve for heparin was constructed in the concentration range of 0.2-6.0 μg/mL with the detection limit as 0.10 μg/mL (3σ) and the molar absorptivity as ε = 6.65 x104L/mol cm