Determination of L‐Lactic Acid Content in Foods by Enzyme‐Based Amperometric Bioreactor

Abstract

A thermostable lactate oxidase (from Aerococcus viridans) based bioreactor was elaborated for l-lactate determination in dairy products. The enzyme was immobilised in a thin-layer enzyme cell connected into a flow injection system with an amperometric detector. The linear measuring range was 0.1-1 mmol/L l-lactate (R 2 = 0.99; linear regression equation: y = 81.2x + 3.3). The detection limit was 0.05 mmol/L. 40 Samples were analyzed per hour. Considering reproducibility: the signals measured were very stable for over 800 injections, after this period the activity of the cell decreased slowly. The method was used for the control of dairy products and for monitoring milk freshness.

Amperometric Biosensor Based on Enzymatic Reactor for Choline Determination in Flow Systems

“…Moreover, the biosensors based on the enzymatic reactors possess the distinctive advantage of much larger amount of the immobilized enzyme resulting in the higher stability of the biosensor and lower enzyme consumption in general. The development of the flow amperometric biosensors with enzyme‐based reactors for the determination of lactate , glucose , sucrose , ascorbic acid , and hydrogen peroxide has been recently reported. To our knowledge, only one biosensor with enzymatic reactor for the determination of Ch has been proposed , which is based on covalently immobilized ChOx on an NH 2 ‐functionalized controlled pore glass support as a reactor and a Pt electrode modified by electrosynthesized polypyrrole film as a transducer for direct H 2 O 2 detection in FIA.…”

A current-mode potentiostat for multi-target detection tested with different lactate biosensors

“…Indeed, L-lactate is one of the major biocompound of health interest. Examples of amperometric biosensors of L-lactate are described by applying L-lactate oxidase (LODx) from various sources [8]. These biosensors use only natural enzymes and suffer from the lack of sufficient stability/functionality to be used for viable devices.…”

Jelölésmentes immunszenzorok fejlesztése probiotikus baktériumok és aflatoxin m1 kimutatására

“…Számos amperometriás (LIN et al, 2008, GAU et al, 2001), potenciometriás (UITHOVEN et al, 2000), voltammetriás (LASCHI et al, 2006, FARABULLINI et al, 2007, konduktometriás (MUHAMMAD-TAHIR et ALOCILJA, 2004) és impedimetriás (RADKE et ALOCILJA, 2005 (ABERL et al, 1994;KÖßLINGER et al;, LARICCHIA-ROBBIO et al, 2004 Zömében tiszta tenyészetek pufferes szuszpenzióit mérték 10 2 -10 5 sejt/ml kimutatási határral, valós élelmiszermintákat nem vizsgáltak (SUBRAMANIAN et al, 2006ab;HAINES et PATEL, 1995;KOUBOVÁ et al, 2001;OH et al, 2004 (GOMES et MALCATA, 1999;GUARNER et SCHAAFSMA, 1998;MARTEAU et al, 1997;SALMINEN et al, 1999) (BRIGIDI et al, 2003;FILTEAU et al, 2013). (PARRA et al 2006;NIKOLAUS et STREHLITZ, 2008;BORI et al, 2012;MONOSÍK et al, 2012;MAZZEI et al, 2007;PALMISANO et al, 2001 táp volt. Az "Aflatoxin" elnevezés egy mozaikszó, az "A" az Aspergillus nemzetséget, a "fla" a flavus fajt jelöli.…”