El-Maghrabey Mahmoud, Seino Shōta, Kishikawa Naoya, Kuroda Naotaka
Graduate School of Biomedical Sciences, Course of Pharmaceutical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan.
Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Mansoura University, Mansoura 35516, Egypt.
Sensors (Basel). 2024 Dec 8;24(23):7844. doi: 10.3390/s24237844.
Herein, we developed a colorimetric method for the determination of Cu and Zn using NBD-G as a novel selective metal sensor. NBD-G was easily synthesized by a nucleophilic substitution reaction between 4-chloro-7-nitro-2,1,3-benzoxadiazole (NBD-Cl) and Girard's Reagent P. The NBD-G solution is yellow, but when it reacts with Cu and Zn, its color changes selectively to red (510 nm) and orange (480 nm), respectively. NBD-G was used as a sensor for Cu and Zn, showing a high sensitivity down to 0.77 µM for Cu and 1.66 µM for Zn. NBD-G could determine both metals simultaneously; thus, it was applied to determine them in multimineral supplements, which showed excellent recoveries. Next, a filter paper impregnated with NBD-G was prepared as a test paper, and a simple, selective, and rapid onsite method for quantifying Cu was developed as, interestingly, the paper showed no change upon the addition of Zn. Next, Cu could be quantified with high selectivity and accuracy by photographing the color change with a smartphone camera and processing the image with Image J. The detection limit for Cu using this method was 3.9 µM. Finally, the NBD-G test paper method was able to satisfactorily quantify Cu spiked into the rainwater.
在此，我们开发了一种比色法，使用NBD-G作为新型选择性金属传感器来测定铜和锌。NBD-G通过4-氯-7-硝基-2,1,3-苯并恶二唑（NBD-Cl）与吉拉德试剂P之间的亲核取代反应轻松合成。NBD-G溶液呈黄色，但当它与铜和锌反应时，其颜色分别选择性地变为红色（510纳米）和橙色（480纳米）。NBD-G用作铜和锌的传感器，对铜的灵敏度高达0.77微摩尔，对锌的灵敏度为1.66微摩尔。NBD-G可以同时测定两种金属；因此，它被应用于多矿物质补充剂中它们的测定，回收率极佳。接下来，制备了浸渍有NBD-G的滤纸作为试纸，并开发了一种简单、选择性且快速的现场定量铜的方法，有趣的是，加入锌时试纸没有变化。接下来，通过用智能手机相机拍摄颜色变化并用Image J处理图像，可以高选择性和高精度地定量铜。使用该方法对铜的检测限为3.9微摩尔。最后，NBD-G试纸法能够令人满意地定量添加到雨水中的铜。
