Abstract
A potentiometric method for the determination of urea in human blood with an ion-sensitive field effect transistor coated with a urease-albumin membrane is described. The urea sensor exhibits a potentiometric response to urea concentrations in the range of 0.1-10 mM with a response time of ca. 3 min. Urea concentrations of diluted serum and plasma can be determined accurately with the sensor. Comparison with an official method (i.e. the urease-indophenol method) gave satisfactory results.
