FT-IR MEASUREMENT OF MERCAPTOUNDECAHYDRODODECABORATE IN HUMAN PLASMA

A simple and rapid method for the quantitative measurement of mercapto undecahydrododecarborate (BSH), (which presently is one of the most us eful agents for Boron Neutron Capture Therapy) in human plasma was dev eloped by using Fourier transform infrared spectroscopy. Different spa cer thicknesses of the liquid sampling cell were examined and the opti mal results were obtained by the 0.05 mm spacer. The subtraction of wa ter absorbance from sample spectra resolved a B-H band at 2493 cm(-1). The quantitative measurement of BSH was carried out by integration of the B-H band in the wavenumber range of 2534-2440 cm(-1). However, at the lower BSH concentration range a visual, inspection of the spectru m to determine the wavenumber range was necessary so as to avoid any n egative areas to be integrated. The lower limit of detection of BSH in aqueous solution and human plasma was 5 mu g ml(-1) (about 2.5 ppm of boron).