Light triggered detection of aminophenyl phosphate with a quantum dot based enzyme electrode

Journal of Nanobiotechnology

Research

Fred Lisdat¹  Gero Göbel¹  Waqas Khalid²  Wolfgang J Parak²  Dominik Hühn²  Jose-Maria Montenegro²  Pilar Rivera-Gil² 

[1] Biosystems Technology, University of Applied Sciences Wildau, Wildau, Germany;Fachbereich Physik and WZMW, Philipps Universität Marburg, Germany;

关键词: Gold Electrode;    Exciton Peak;    Photocurrent Response;    Phenyl Phosphate;    Polyelectrolyte Layer;   

DOI  :  10.1186/1477-3155-9-46

 received in 2011-08-18, accepted in 2011-10-07,  发布年份 2011

来源: Springer

【 摘 要 】

An electrochemical sensor for p-aminophenyl phosphate (p APP) is reported. It is based on the electrochemical conversion of 4-aminophenol (4AP) at a quantum dot (QD) modified electrode under illumination. Without illumination no electron transfer and thus no oxidation of 4AP can occur. p APP as substrate is converted by the enzyme alkaline phosphatase (ALP) to generate 4AP as a product. The QDs are coupled via 1,4-benzenedithiol (BDT) linkage to the surface of a gold electrode and thus allow potential-controlled photocurrent generation. The photocurrent is modified by the enzyme reaction providing access to the substrate detection. In order to develop a photobioelectrochemical sensor the enzyme is immobilized on top of the photo-switchable layer of the QDs. Immobilization of ALP is required for the potential possibility of spatially resolved measurements. Geometries with immobilized ALP are compared versus having the ALP in solution. Data indicate that functional immobilization with layer-by-layer assembly is possible. Enzymatic activity of ALP and thus the photocurrent can be described by Michaelis- Menten kinetics. p APP is detected as proof of principle investigation within the range of 25 μM - 1 mM.

【 授权许可】

Unknown   
© Khalid et al; licensee BioMed Central Ltd. 2011. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.