基于酶辅助的比率型电化学适配体传感器用于前列腺特异性抗原检测  

An enzyme-assisted ratiometric electrochemical aptasensor for the detection of prostate specific antigen

作　　者：关志敏 谢瑶瑶 马会凯 王萍[1] GUAN Zhimin;XIE Yaoyao;MA Huikai;WANG Ping(College of Basic Medicine and Forensic Medicine,Henan University of Science and Technology,Luoyang 471000,China)

机构地区：[1]河南科技大学基础医学与法医学院,洛阳471000

出　　处：《分析试验室》2024年第5期615-620,共6页Chinese Journal of Analysis Laboratory

基　　金：国家自然科学基金(61701171)资助。

摘　　要：基于核酸外切酶Ⅲ(ExoⅢ)辅助靶标循环策略,构建了比率型电化学适配体传感器,并用于前列腺特异性抗原(PSA)的检测。利用亚甲基蓝(MB)作为内置参考信号,当PSA存在时,发夹探针1(HP1)的适配体序列与PSA特异性结合,引起ExoⅢ的2次切割过程,从而实现2次循环扩增反应,导致电极上更多的MB标记的发夹探针3(MB-HP3)被切割;再加入二茂铁(Fc)标记的DNA链(Fc-DNA)与MB-HP3酶切后的片段进行杂交;最终,Fc的信号(I_(Fc))增加,而MB的信号(I_(MB))基本保持不变。在最佳条件下,I_(Fc)/I_(MB)与PSA浓度的对数值在0.001~100 ng/mL范围内呈良好的线性关系,检出限为0.24 pg/mL。该传感器在临床实际样品检测中具有较好的应用前景。A ratiometric electrochemical aptasensor based on exonucleaseⅢ(ExoⅢ)-assisted target recycling strategy was developed for the detection of prostate specific antigen(PSA).Methylene blue(MB)was used as a built-in reference signal.In the presence of PSA,the specific binding between the aptamer region of hairpin probel(HP1)and PSA could trigger two cleavage processes of ExoⅢ,thus achieving two cyclic amplification reactions,accompanying by more MB-labeled hairpin probe 3(MB-HP3)on the electrode to be digested.The addition of ferrocene(Fc)-labeled DNA(Fc-DNA)was hybridized with the digested fragment of MB-HP3,resulting in an enhancement of Fc signal(I_(Fc)),while the signal of MB(I_(MB))remained basically unchanged.Under the optimal conditions,a linear relationship was obtained between the I(Fc)/I_(MB)value and the logarithm value of PSA concentration in the range from 0.001 to 100 ng/mL,and the detection limit was 0.24 pg/mL.The sensor has a good application prospect in determination of PSA in clinical samples.

关 键 词：前列腺特异性抗原 核酸外切酶Ⅲ 比率型电化学适配体传感器 

分 类 号：O657.1[理学—分析化学]