APPLICATION OF XANTHENE DERIVATIVES FOR ANALYTICAL-CHEMISTRY .92. SPECTROPHOTOMETRIC DETERMINATION OF PROTEIN WITH CHROMAZUROL B-BERYLLIUM(II) COMPLEX BY MANUAL AND FLOW-INJECTION METHODS

A spectrophotometric study of protein/Chromazurol B/beryllium(II) system is reported. In the manual spectrophotometric method, Beer's law is obeyed for protein (as human serum albumin, HSA) concentrations up to 150-mu-g/10 ml. This procedure is about 3 times more sensitive than the Pyrogallol Red-molybdenum (VI) method. In the flow-injection method which employs a single-channel flow manifold system, the calibration graph is linear for the HSA range from 0.1 to 1-mu-g/10-mu-l by direct injection. Results obtained by the present manual method and the Pyrogallol Redmolybdenum (VI) method agree with each other in the determination of urinary proteins. No significant difference in results was observed between the manual and flow-injection methods.