Nanomedicine and Nanotoxicology Group, São Carlos Institute of Physics, University of São Paulo, CP 369, 13560-970, São Carlos, SP, Brazil; Federal University of Espírito Santo, Av Marechal Campos 1468, Vitória, ES 29.040-090, Brazil.
Nanomedicine and Nanotoxicology Group, São Carlos Institute of Physics, University of São Paulo, CP 369, 13560-970, São Carlos, SP, Brazil; Health and Technological Innovation, Universidad Simón Bolívar, Facultad de Ingenierías, Barranquilla, 080002, Colombia.
Talanta. 2023 Aug 1;260:124586. doi: 10.1016/j.talanta.2023.124586. Epub 2023 Apr 22.
Ochratoxin A (OTA) is a nephrotoxic and carcinogenic mycotoxin frequently found in coffee, which directly impacts human health and the economy of many countries. For this reason, there has been a growing need for simple and sensitive tools for the on-site detection of this mycotoxin. In this study, we developed a label-free impedimetric immunosensor to detect OTA. The biosensor was built on a thin-film gold electrode evaporated on glass substrtes, modified with a self-assembled cysteamine monolayer and anti-OTA antibodies. Atomic force microscopy and Microspectroscopy RAMAN confirmed the successful functionalization of the electrodes. The biosensor performance was evaluated by electrochemical impedance spectroscopy and the measurements indicated a linear relationship between the change in the impedance values and the OTA concentration in the range from 0.5 to 100 ng mL with a limit of detection of 0.15 ng mL. The biosensor was highly selective and did not suffer matrix interference when analyzed in coffee samples. Furthermore, considering the small sample volumes, the short time required for analysis, and the possibility of miniaturization, the developed biosensor represents a promising analytical device for on-site coffee quality analyses.
赭曲霉毒素 A（OTA）是一种常见于咖啡中的肾毒性和致癌性真菌毒素，直接影响人类健康和许多国家的经济。因此，人们越来越需要用于现场检测这种真菌毒素的简单而灵敏的工具。在这项研究中，我们开发了一种用于检测 OTA 的无标记阻抗免疫传感器。该生物传感器构建在玻璃衬底上蒸发的薄膜金电极上，并用自组装半胱氨酸单层和抗 OTA 抗体进行修饰。原子力显微镜和 Microspectroscopy RAMAN 证实了电极的成功功能化。通过电化学阻抗光谱评估了生物传感器的性能，测量结果表明，在 0.5 至 100ng/mL 的范围内，阻抗值的变化与 OTA 浓度之间存在线性关系，检测限为 0.15ng/mL。该生物传感器具有高度选择性，在分析咖啡样品时不受基质干扰。此外，考虑到小样本量、分析所需的短时间以及小型化的可能性，开发的生物传感器代表了用于现场咖啡质量分析的有前途的分析设备。
