Creatinine enzymatic analysis

H.-L. Lee and S.-C. Chen, Microchip capillary electrophoresis with electrochemical detector for precolumn enzymatic analysis of glucose, creatinine, uric acid and ascorbic acid in urine and serum, Talanta, 64 (2004) 750-757. 

For determination of creatinine, the nonspecific Jaffe method, although subject to perturbation by many interfering substances of endogenous and exogenous origin, is the most widely used. However, a batchwise kinetic procedure and flow injection analysis have shown the possibility to determine creatinine in human urine samples by this reaction, free from any systematic error. Enzymatic assays have higher specificities, but still suffer... 

Diagnosis of renal problems, xanthinuria, and toxemia of pregnancy via determination of the ratio of hypoxanthine to xanthine in plasma is facilitated by the use of biosensors. Xanthine oxidase immobilized on aminopropyl-CPG (controlled pore glass) activated with glutaraldehyde oxidizes hypoxanthine first to xanthine and then to uric acid. Use of an IMER with biosensors for hypoxanthine, xanthine, and uric acid provides the necessary data. Pre- or postcolumn enzymatic reactions catalyzed by creatinine deiminase, urease, alkaline phosphatase, ATPase, inorganic pyrophosphatase, or arylsufatase facilitate analysis of uremic toxins (simultaneous detection of electrolytes, serum urea, uric acid, creatinine, and methylguanidine). 

B. A. Petersson, E. H. Hansen, and J. RdiiCka, Enzymatic Assay by Flow Injection Analysis with Detection by Chemiluminescence Determination of Glucose, Creatinine, Free Cholesterol and Lactic Acid Using an Integrated FIA Microconduit. Anal. Lett., 19 (1986) 649. 

The common spectrophotometric method for creatinine detection is based on the Jaffe reaction between creatinine and picric acid in alkaline solution to form a red-yellow complex. However, substances of endogenous and exogenous origin usually cause interference. In spite of these problems, the colorimetric method of Jaffe is still used today for the determination of creatinine in biological samples.A batchwise kinetic procedure and flow injection analysis have shown the possibility to determine creatinine in human urine samples by this reaction, free from any systematic error.Enzymatic methods have been reported to increase specificity/selectivity but still suffer from interferences. To avoid these problems, new analytical methods were developed. Several electtoanalytical techniques, based on potentiometric or amperometric detection, are available. Potentiometric methods using several sensors and biosensors were known for the... 

---