Novel potentiornetric sensing of creatinine

The potentiometric sensing device for quantitative estimation of creatinine is reported. The sensor comprises a bi-enzymatic reactor and potentiometric urea biosensor. The bi-enzymatic reactor is developed by sandwiching two enzymes, creatininase and creatinase, within two layers of organically modified sol-gel glass (ORMOSEL). The urea biosensor is developed by immobilizing urease on a new pH sensor developed by p-toluenesulfonate doped polyaniline-modified electrode. The polyaniline-modified electrode is developed by potentiodynamic electropolymerization of aniline based on sweeping the electrode potential within -0.7 to 2.0V versus Ag/AgCl in non-aqueous medium in the presence of tetraethylanimonium p-toluenesulfonate as supporting electrolyte. The enzyme reactor converts creatinine into urea. The urea formed through bienzymatic reactor is monitored by new urea biosensor. The typical results on urea sensing, pH sensing and creatinine sensing are reported. The detection limit of the new sensor for urea is 5 muM and for creatinine is 100 muM. (C) 2003 Elsevier B.V. All rights reserved.