A G-quadruplex aptamer based impedimetric sensor for free lysine and arginine

SENSORS AND ACTUATORS B-CHEMICAL

卷:243

Article

Carter, Z. A.¹  Kataky, R.¹ 

[1] Univ Durham, Dept Chem, South Rd, Durham DH1 3LE, England

关键词: G-quadruplex;    Aptamer;    Impedance;    AFM;    Amino acids;    Food;   

DOI  :  10.1016/j.snb.2016.12.010

来源: Elsevier

【 摘 要 】

This paper describes a label free sensor for the sensitive detection of certain, basic primary amino acids containing free ethyl and methyl amino acids. The control of interfacial electron transfer of a G-quadruplex DNA aptamer, using a Fe(CN)(6)(3-/4-) redox probe responds rapidly to variations in arginine and lysine concentrations, but not to histidine, using non-labelled, impedance spectroscopy (EIS) detecti on. Two binding aptamer binding regimes were observed. At the low concentration range (0-0.15 mu g/mL), selectivity between lysine and arginine was apparent with limits of detection at approximately 0.5 mu Mand 1.6 pM respectively. At higher levels of concentrations, 0.15-10 mu g/mL, selectivity was limited. The aptamer was immobilised on gold substrates ensuring optimal probe density which was monitored by Atomic Force Microscopy. Initial studies indicate that the relative change in charge transfer resistance (Rct) values can be used as a parameter for monitoring free lysine to arginine ratios and free total lysine and arginine for direct detection of total lysine and arginine in food samples (milk, egg white and yoghurt) in Tris/HCI buffer, demonstrating its potential in many applications. (C) 2016 Elsevier B.V. All rights reserved.

【 授权许可】

Free