Premium
Amperometric Bi‐enzyme based biosensor for the detection of lactose—characterization and application
Author(s) -
Pfeiffer Dorothea,
Ralis Edmundas V.,
Makower Alexander,
Scheller Frieder W.
Publication year - 1990
Publication title -
journal of chemical technology and biotechnology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.64
H-Index - 117
eISSN - 1097-4660
pISSN - 0268-2575
DOI - 10.1002/jctb.280490307
Subject(s) - biosensor , amperometry , lactose , chromatography , chemistry , characterization (materials science) , enzyme , biochemistry , nanotechnology , materials science , electrode , electrochemistry
Based on the glucose oxidase‐β‐galactosidase sequence an enzyme probe for the specific determination of lactose has been developed. β‐Galactosidases from different sources have been compared, the sensor containing β‐galactosidase from Curvularia inaequalis has been characterized in respect of optimal pH, enzyme loading, apparent activity and functional stability. The response of the bi‐enzyme probe depends linearly on lactose concentration between 0.02 and 3.00 mmol dm −3 . The application to different milk and foodstuff samples resulted in good correlations toward enzymatic photometric (y = (0.956x‐1.67) mmol dm −3 ) and infrared detection (y = (1.0772x‐0.3909)%). Using a measuring frequency of 100 h −1 the serial imprecision is about 2% for diluted milk, urine, or foodstuff samples.