FAST ENZYMATIC DETERMINATION OF CREATININE IN SERUM

THE LONG-TERM OBJECTIVE OF THIS RESEARCH IS TO PROVIDE FAST, INTERFERENCE-FREE CHEMISTRIES FOR THE CLINICAL LABORATORY USING IMMOBILIZED ENZYMES AND SENSORS. THE SPECIFIC AIM OF THIS PROJECT IS TO PROVE THAT IT IS FEASIBLETO MEASURE CREATININE IN LESS THAN 2 MINUTES USING IMMOBILIZED ENZYMES AND SENSORS. BECAUSE OF THE SPECIFICITY OF THE ENZYME CREATINASE, THE ASSAY SHOULD BE INTERFERENCE FREE. ALL FAST (LESS THAN 3 MINUTES) CURRENT METHODOLOGIES FOR MEASURING CREATININE HAVEINTERFERENCE FROM KETOACIDS, DRUGS, AND PROTEINS. BECAUSE MANY LONG-TERM DIABETIC PATIENTS CAN BE KETOTIC AND SUFFER FROM KIDNEY DYSFUNCTION, AN ACCURATE CREATININE TEST IS OF GREAT IMPORTANCE. THE ASSAY WILL BE BASED ON IMMOBILIZING CREATININE AMIDOHYDROLASE AND HYDROLYZING CREATININE TO CREATINE. THE SAMPLE BEFORE AND AFTER HYDROLYSIS WILL BE MEASURED BY THE KINETIC JAFFE METHOD. THE DIFFERENCE IN RATES IS DIRECTLY PROPORTIONAL TO THE CREATININE CONCENTRATION IN THE SAMPLE. THIS IMMOBILIZED ENZYME/SENSOR TECHNOLOGY COULD SUPPLANT BOTH THE COMMON JAFFE CHEMICAL METHOD FOR MEASURING CREATININE AND THE SLOW, EXPENSIVE OPTICAL ENZYMATIC PROCEDURES AS THE STANDARD TECHNIQUE FOR THE CLINICAL LABORATORY.