β-激动剂核酸适配体电化学生物传感器的研制

A Novel Aptasensor for Electrochemistry Detection of β-agonists

β-激动剂是苯乙醇胺类化合物在芳香环和末端氨基部位被不同官能团取代而产生的一类化合物。β-激动剂具有营养再分配作用,当食用含有β-激动剂的食物后β-激动剂会在人体内积累引起急性或慢性中毒。因此,建立一个快速检测β-激动剂的方法对于食品安全控制是十分重要的。通过等温滴定量热技术筛选出一条对β-激动剂有高亲和力(Kd=3.34×10-5mol/L)的核酸适配体,AP-Ago。AP-Ago为22bp的单链DNA。利用该适配体(AP-Ago)作为识别分子成功构建了一个非标记型电化学适配体生物传感器,该传感器对莱克多巴胺、克伦特罗、沙丁胺醇、苯乙醇胺和丙卡特罗敏感。对莱克多巴胺、克伦特罗、沙丁胺醇、苯乙醇胺和丙卡特罗的检测限分别为0.04ng/ml、0.35pg/ml、0.53pg/ml、1.0pg/ml和1.73pg/ml。检测时间为15min。该适配体传感器具有良好的检测重现性(RSD=2.09%)。研究表明,适配体传感器可以被发展成为一种快速检测样品中一种或多种β-激动剂的方法。

β-agonists are phenylethanolamines with different substituent groups on the aromatic ring and the terminal amino group which have the effect of nutrition redistribution and could accumulate in body tissues causing acute or chronic poisoning when consumed.Therefore,establishing a method for rapid screening of β-agonists is very important to food safety control.The aptamer named AP-Ago is screened by Isothermal Titration Calorimetric method.AP-Ago is a single-strand DNA and 22 base-pairs.The dissociation constant(Kd) to PHL is 3.34 × 10-5mol/L.A labeled free electrochemical aptasensor is developed with AP-Ago,which is sensitive to phenylethanolamine(PHL),clenbuterol(CLB),ractopamine(RAC),salbutamol(SAL) and procaterol(PRO).The detection limits are 0.04 ng/ml(RAC),0.35 pg/ml(CLB),1.0pg/ml(PHL),0.53 pg/ml(SAL) and 1.73 pg/ml(PRO),respectively.The detection time is 15 min.This aptasensor also have a good reproductivity of the relative standard deviation(RSD) at 2.09%.The aptasensor can be developed as a rapid screening means with β-agonists(may be one or more) in sample.