SCREENING OF URINARY COPROPORPHYRIN USING CLOUD POINT EXTRACTION AND CHEMILUMINESCENCE DETECTION

A simple screening test was developed for the sensitive and selective measurement of urinary coproporphyrin. In this screening test, efficie nt and selective extraction/pre-concentration of coproporphyrin from t he aqueous medium(urine) into a much smaller volume phase containing a common non-ionic surfactant (Triton X-100) and ethyl acetate was acco mplished by the addition of a relatively large amount of a cloud point depressing electrolyte (K3PO4) into the sample solution to effect clo ud point separation. Sensitive and selective detection of coproporphyr in in the mixed Triton X-100 and ethyl acetate phase was performed via chemical excitation using the peroxyoxalate chemiluminescence reactio n. The effects of surfactant and cations (from the cloud point depress ing electrolyte) on the chemiluminescence intensity of coproporphyrin were briefly investigated. Furthermore, the spectrum of urinary coprop orphyrin obtained using the present chemiluminescence method was brief ly compared with that obtained from fluorescence method.