IMPROVED HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC METHOD FOR THE DETERMINATION OF TRIS(HYDROXYMETHYL)AMINOMETHANE (THAM) IN HUMAN PLASMA, ERYTHROCYTES, AND WHOLE-BLOOD

A sensitive high performance liquid chromatographic (HPLC) assay was d eveloped to quantitate the organic amine proton-acceptor, tris(hydroxy methyl)aminomethane (THAM) in human plasma, erythrocytes, and whole bl ood. An aliquot of the sample was heat evaporated (200 degrees C for 2 h), derivatized, extracted, and then injected onto a symmetry Cs colu mn. The UV absorbance of the effluent was monitored at 237 mn. 2-Amino -2-methyl-1,3-propanediol was found to be an appropriate internal stan dard. The method has been applied to quantitate the samples from patie nts undergoing orthotopic liver transplantation. The assay has also be en employed to assess the in vitro time of THAM-uptake into the erythr ocytes from blood samples incubated at 37 degrees C.