ABSTRACT
Therapeutic drug monitoring for serum Gentamicin is very useful for infectious patients. The most common methods for measuring concentration of Gentamicin in body fluids are microbiological assay, rasioimmunoassay (RIA), enzyme immunoassay (EMIT) and high pressure liquid chromatography (HPLC), The purpose of this study was to compare two new methods, an enzyme multiplied immunoassay test (EMIT; Suva Corp.) and high pressure liquid Chromatography with fluorescence detection precolumn derivatization, reversed Phase column. Forty serum samples were obtained from patients in the kidney disease unit, Department of Medicine, Siriraj Hospital. The two methods were evaluated on the basis of accuracy, limitation, specificity and cost. EMIT showed a high degree of accuracy and lesser limitation. But this method of HPLC could not determine values for serum gentamicin at levels below 4 ตg/ml. Total cost which included equipment for both procedures was similar. Unit cost for this method of HPLC was cheaper than EMIT but was time consuming and required experience. Both methods were specific for serum Gentamicin.