Monitoring the enzymatic conversion of urea to ammonium by conventional or microchip capillary electrophoresis with contactless conductivity detection.
Capillary electrophoresis with contactless conductivity detection was used to directly quantify the ammonium produced in the enzymatic conversion of urea with urease. This allowed the characterization of the reaction without having to use more elaborate indirect optical methods for quantification. The maximum rate of reaction, V(max), was determined as 5.1 mmol x mL(-1) x min(-1), and the Michaelis-Menten constant, K(m), was determined as 16 mM. Furthermore, the method was successfully applied to the determination of urea in clinical samples of human blood by using a conventional capillary and a microchip device.
Schuchert-Shi
Aiping
A
Department of Chemistry, University of Basel, Spitalstrasse 51, 4056 Basel, Switzerland.
Hauser
Peter C
PC
D019075:Electrophoresis, Capillary / Q000379:methods*; D046209:Electrophoresis, Microchip / Q000379:methods*; D006801:Humans; D007700:Kinetics; D000644:Quaternary Ammonium Compounds / Q000032:analysis* / Q000378:metabolism; D014508:Urea / Q000032:analysis* / Q000097:blood / Q000378:metabolism; D014510:Urease / Q000378:metabolism
D000644:Quaternary Ammonium Compounds; D014508:Urea; D014510:Urease