Functional Nanomaterials Laboratory, Morphology Department, Federal University of Espírito Santo (UFES), Av Marechal Campos 1468, Vitória 29040-090, ES, Brazil.
Telecommunications Laboratory, Electrical Engineering Department, Federal University of Espírito Santo (UFES), Av Fernando Ferrari 514, Vitória 29075-910, ES, Brazil.
Biosensors (Basel). 2023 Apr 30;13(5):512. doi: 10.3390/bios13050512.
In this study, we developed a biosensor based on the localized surface plasmon resonance (LSPR) phenomenon of gold nanoparticles (AuNPs) to detect the widely used herbicide glyphosate in food samples. To do so, either cysteamine or a specific antibody for glyphosate were conjugated to the surface of the nanoparticles. AuNPs were synthesized using the sodium citrate reduction method and had their concentration determined via inductively plasma coupled mass spectrometry. Their optical properties were analyzed using UV-vis spectroscopy, X-ray diffraction, and transmission electron microscopy. Functionalized AuNPs were further characterized via Fourier-transform infrared spectroscopy, Raman scattering, Zeta potential, and dynamic light scattering. Both conjugates succeeded in detecting the presence of glyphosate in the colloid, although nanoparticles functionalized with cysteamine tended to aggregate at high concentrations of the herbicide. On the other hand, AuNPs functionalized with anti-glyphosate functioned at a broad concentration range and successfully identified the presence of the herbicide in non-organic coffee samples and when it was added to an organic coffee sample. This study demonstrates the potential of AuNP-based biosensors to detect glyphosate in food samples. The low-cost and specificity of these biosensors make them a viable alternative to current methods for detecting glyphosate in foodstuffs.
在这项研究中，我们开发了一种基于金纳米粒子（AuNPs）局部表面等离子体共振（LSPR）现象的生物传感器，用于检测食品样品中广泛使用的除草剂草甘膦。为此，要么将半胱氨酸或针对草甘膦的特异性抗体连接到纳米粒子的表面。AuNPs 是使用柠檬酸钠还原法合成的，并通过电感耦合等离子体质谱法确定其浓度。它们的光学性质通过紫外-可见分光光度法、X 射线衍射和透射电子显微镜进行分析。通过傅里叶变换红外光谱、拉曼散射、Zeta 电位和动态光散射进一步对功能化的 AuNPs 进行了表征。两种缀合物都成功地在胶体中检测到了草甘膦的存在，尽管用半胱氨酸功能化的纳米粒子在除草剂的高浓度下往往会聚集。另一方面，用抗草甘膦功能化的 AuNPs 在较宽的浓度范围内起作用，并成功地在非有机咖啡样品和添加到有机咖啡样品中时检测到了除草剂的存在。本研究证明了基于 AuNP 的生物传感器在检测食品样品中的草甘膦方面的潜力。这些生物传感器的低成本和特异性使其成为当前检测食品中草甘膦的方法的可行替代品。
