Microcystins are potent hepatotoxins produced by cyanobacteria, which proliferate in wastewaters with high nutrient content. Due to their high toxicity and potential risk to human health, even at low concentrations, the development of a sensitive and rapid method for the monitoring of microcystin‐LR (MC‐LR) in water samples is of great importance. In this context, a new direct electrochemical nano‐immunosensor for MC‐LR detection using the liquid crystal (E)‐1‐decyl‐4‐[(4‐decyloxyphenyl)diazenyl]pyridinium bromide (Br‐Py) as a redox probe and gold nanoparticles stabilized in bovine serum albumin (AuNP‐BSA) is described herein. The microcystin‐LR antibody (anti‐MC‐LR) was covalently immobilized using N‐(3‐dimethylaminopropyl)‐N‐ethylcarbodiimide hydrochloride (EDC) and N‐hydroxysuccinimide (NHS) on an AuNP‐BSA/BrPy film. The proposed sensor response is based on the inhibition of the Br‐Py electrochemical signal after the specific interaction of MC‐LR with immobilized anti‐MC‐LR on the electrode surface. The electrochemical behavior of the immunosensor was studied by square‐wave voltammetry (SWV) and electrochemical impedance spectroscopy (EIS). Under optimized conditions, using SWV and an incubation time of 15 min, the immunosensor exhibits a linear response to MC‐LR concentrations of 0.05 to 500.0 ng mL⁻¹ with a detection limit of 0.05 ng mL⁻¹. The anti‐MC‐LR/AuNP‐BSA/Br‐Py/GCE was successfully applied in the determination of MC‐LR in spiked seawater samples.

中文翻译：

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海水中微囊藻毒素-LR的直接电化学纳米免疫传感器

微囊藻毒素是蓝细菌产生的有效肝毒素，在高养分含量的废水中增殖。由于它们即使在低浓度下也具有高毒性和对人体健康的潜在风险，因此开发一种灵敏而快速的监测水样中微囊藻毒素-LR（MC-LR）的方法非常重要。在这种情况下，使用液晶（E）-1-癸基-4-[[（4-癸氧基苯基）二氮烯基]溴化吡啶鎓（Br-Py）作为氧化还原探针和MC-LR检测的新型直接电化学纳米免疫传感器。本文描述了在牛血清白蛋白（AuNP-BSA）中稳定的金纳米颗粒。使用N-（3-二甲基氨基丙基）-N-乙基碳二亚胺盐酸盐（EDC）和N-羟基琥珀酰亚胺（NHS）将微囊藻毒素LR抗体（抗MC-LR）共价固定在AuNP-BSA / BrPy膜上。拟议的传感器响应基于对MC‐LR与固定在电极表面的抗MC‐LR特异性相互作用后对Br‐Py电化学信号的抑制作用。通过方波伏安法（SWV）和电化学阻抗谱（EIS）研究了免疫传感器的电化学行为。在最佳条件下，使用SWV和15分钟的孵育时间，免疫传感器对MC‐LR浓度为0.05至500.0 ng mL的溶液表现出线性响应^-1的检出限为0.05 ng mL ^-1。抗MC‐LR / AuNP‐BSA / Br‐Py / GCE已成功用于测定加标海水样品中的MC‐LR。