Application of enzyme field-effect transistor sensor arrays as detectors in a flow-injection system for simultaneous monitoring of medium components. Part I. Preparation and calibration.

✍ Scribed by T. Kullick; M. Beyer; J. Henning; T. Lerch; R. Quack; A. Zeitz; B. Hitzmann; T. Scheper; K. Schürgerl

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 525 KB
• Volume: 296
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/0003-2670(94)80245-9

✦ Synopsis

Enzymes were (co)hnmobilized on the pH-sensitive gates of an eightchannel field-effect transistor @ET).

Glucose was analysed with a glucose dehydrogenase (GDH) FET, maltose with a coimmobilized maltase (MAL)/GDH FET, sucrose with a cohnmobilized invertase (INV)/GDH FET, lactose with a /3-galactosidase (/3-GAL)/galactose dehydrogenase (GALDHMusion protein FET and ethanol with a coimmobilized alcohol dehydrogenase (ADI-D/aldehyde dehydrogenase (ALDH) FET. These EnFETs were integrated in FIA systems, calibrated and characterized with respect to buffer capacity, pH value, stirrer speed and NAD concentration and cross sensitivity. On account of the pH and buffer capacity sensitivity of the signals of the EnFETs, the pH value was monitored with a pH-FET of the array and the buffer capacity and substrate concentration were calculated from the shape of the signal of the FIA system. The EnFETs were stored at 4°C for many months without activity loss. They have satisfactory activity for performing a large number of analyses.