School of Food Science and Technology, Henan University of Technology, Zhengzhou, Henan 450001, PR China.
School of Food Science and Technology, Henan University of Technology, Zhengzhou, Henan 450001, PR China.
Sci Total Environ. 2022 Dec 20;853:158676. doi: 10.1016/j.scitotenv.2022.158676. Epub 2022 Sep 9.
Excessive residues of semicarbazide (SEM) can accumulate in animals after the original drug has been abused, posing a risk to human health. Herein, based on multifunctional silica-initiated dual mode signal response, a novel competitive-type immunosensor was constructed for ultrasensitive detection of SEM. As a preliminary signal amplification platform for immunosensors, polyethyleneimine reduced graphene oxide composite gold nanorods (PEI-rGO/AuNRs) modified gold electrodes (AuE) provide a high specific surface area and high electrical conductivity. The thionine-aminated silica nanospheres-AuPt (thi-SiO@AuPt) were synthesized by a racile coprecipitation method for enzyme immobilization and redox species loading. The multifunctional silica nanosphere conjugated with labeling antibodies (Ab) was employed as an immunoprobe. The per unit concentration target of SEM can be determined by differential pulse voltammetry (DPV) to detect the thi loaded on the immunoprobe, which can also be determined by square wave voltammetry (SWV) to detect the current generated by the reaction system of HO and hydroquinone (HQ) catalyzed by the immunoprobe with peroxidase. Under optimal conditions, the proposed immunosensor displayed a wide linear range from 1 μg-0.01 ng/mL and low detection limits (S/N = 3) of 0.488 pg/mL and 0.0157 ng/mL, respectively. Ultimately, the developed method exhibits excellent performance in practical applications, providing promising probabilities for SEM detection.
氨基脲（SEM）的过量残留会在动物体内蓄积，对人类健康构成威胁。在此，基于多功能二氧化硅引发的双模式信号响应，构建了一种用于 SEM 超灵敏检测的新型竞争性免疫传感器。作为免疫传感器的初步信号放大平台，聚乙烯亚胺还原氧化石墨烯复合金纳米棒（PEI-rGO/AuNRs）修饰的金电极（AuE）提供了高比表面积和高导电性。采用无规共沉淀法合成了噻吩胺化二氧化硅纳米球-AuPt（thi-SiO@AuPt），用于酶固定和氧化还原物种负载。多功能二氧化硅纳米球与标记抗体（Ab）偶联，作为免疫探针。通过差分脉冲伏安法（DPV）检测免疫探针上负载的 thi 可以确定 SEM 的单位浓度目标，也可以通过方波伏安法（SWV）检测免疫探针与辣根过氧化物酶反应体系中 HO 和对苯二酚（HQ）的电流来确定。在最佳条件下，所提出的免疫传感器显示出从 1 μg-0.01 ng/mL 的宽线性范围和低检测限（S/N = 3）分别为 0.488 pg/mL 和 0.0157 ng/mL。最终，所开发的方法在实际应用中表现出优异的性能，为 SEM 检测提供了有前景的可能性。
