Li Yongfang, Wang Zijun, Chen Xuan, Yi Zhijian, Wang Rui
School of Food Science and Engineering, Foshan University, Foshan, 528231, China.
Human Phenome Institute, State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200438, China.
Sci Rep. 2024 Aug 8;14(1):18433. doi: 10.1038/s41598-024-69626-7.
Electrochemical detection is favorable for the rapid and sensitive determination of heavy metal cadmium. However, the detection sensitivity needs to be further improved, and a portable, low-cost device is needed for on-site detection. Herein, an in-situ bismuth modified pre-anodized screen-printed carbon electrode (SPCE) was developed for Cd determination by square wave anodic stripping voltammetry (SWASV). The in-situ bismuth modification enhances the enrichment of Cd, and together with pre-anodization improve the electron transfer rate of electrode, thus enhancing the detection sensitivity. The electrode modification method combines pre-anodization and in-situ bismuth deposition, which is very easy and effective. Furthermore, a self-made PSoC Stat potentiostat coupled with a stirring device was fabricated for portable and low-cost electrochemical detection. After comprehensive optimization, the developed method can reach a testing time of 3 min, a detection limit of 3.55 μg/L, a linear range of 5-100 μg/L, and a recovery rate of 91.7-107.1% in water and rice samples for Cd determination. Therefore, our method holds great promise for the rapid, sensitive and on-site determination of Cd in food samples.
电化学检测有利于快速、灵敏地测定重金属镉。然而，检测灵敏度仍需进一步提高，并且需要一种便携式、低成本的设备用于现场检测。在此，开发了一种原位铋修饰的预阳极氧化丝网印刷碳电极（SPCE），用于通过方波阳极溶出伏安法（SWASV）测定镉。原位铋修饰增强了镉的富集，并且与预阳极氧化一起提高了电极的电子转移速率，从而提高了检测灵敏度。电极修饰方法结合了预阳极氧化和原位铋沉积，简单且有效。此外，还制作了一种自制的PSoC Stat恒电位仪与搅拌装置相结合，用于便携式和低成本的电化学检测。经过全面优化，所开发的方法在测定水和大米样品中的镉时，测试时间可达3分钟，检测限为3.55μg/L，线性范围为5 - 100μg/L，回收率为91.7 - 107.1%。因此，我们的方法在食品样品中镉的快速、灵敏和现场测定方面具有很大的潜力。
