Flow electrochemical biosensors based on enzymatic porous reactor and tubular detector of silver solid amalgam

0392185 - ÚFCH JH 2014 RIV NL eng J - Journal Article
Josypčuk, Bohdan - Barek, J. - Josypčuk, Oksana
Flow electrochemical biosensors based on enzymatic porous reactor and tubular detector of silver solid amalgam.
Analytica Chimica Acta. Roč. 778, MAY 2013 (2013), s. 24-30. ISSN 0003-2670. E-ISSN 1873-4324
R&D Projects: GA ČR GAP206/11/1638
Institutional support: RVO:61388955
Keywords : flow analysis * amperometry * silver solid amalgam
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 4.517, year: 2013

A flow amperometric enzymatic biosensor for the determination of glucose was constructed. The biosensor consists of a flow reactor based on porous silver solid amalgam (AgSA) and a flow tubular detector based on compact AgSA. The preparation of the sensor and the determination of glucose occurred in three steps. First, a self-assembled monolayer of 11-mercaptoundecanoic acid (MUA) was formed at the porous surface of the reactor. Second, enzyme glucose oxidase (GOx) was covalently immobilized at MUA-layer using N-ethyl-N′-(3-dimethylaminopropyl) carboimide and N-hydroxysuccinimide chemistry. Finally, a decrease of oxygen concentration (directly proportional to the concentration of glucose) during enzymatic reaction was amperometrically measured on the tubular detector under flow injection conditions. The following parameters of glucose determination were optimized with respect to amperometric response: composition of the mobile phase, its concentration, the potential of detection and the flow rate. The calibration curve of glucose was linear in the concentration range of 0.02–0.80 mmol L−1 with detection limit of 0.01 mmol L−1. The content of glucose in the sample of honey was determined as 35.5 ± 1.0 mass % (number of the repeated measurements n = 7; standard deviation SD = 1.2%; relative standard deviation RSD = 3.2%) which corresponds well with the declared values. The tested biosensor proved good long-term stability (77% of the current response of glucose was retained after 35 days).
Permanent Link: http://hdl.handle.net/11104/0221127