Selective lead ion sensing via cotton pad-based Na2EDTA capped AuNPs: A smartphone-assisted colorimetric method

作     者：Sultana, Evana Rana, Md Zewel Al Mamun, Muhammad Shamim Saad Aly, Mohamed Aly Khedr, Ghada E. Ahmed, Jamil Alahmad, Waleed 

作者机构：Chemistry Discipline Khulna University Khulna9208 Bangladesh Chemical & Materials Engineering University of Nevada Reno 1664 North Virginia Street RenoNV89557 United States  Guangdong Shenzhen518055 China Department of Analysis and Evaluation Egyptian Petroleum Research Institute Cairo11727 Egypt Department of Chemistry Faculty of Science at Chulalongkorn University Bangkok10330 Thailand School of Electrical and Computer Engineering Georgia Institute of Technology AtlantaGA30332 United States 

出 版 物：《Chemosphere》 (Chemosphere)

年 卷 期：2025年第372卷

页      面：144095页

核心收录：

学科分类：0810[工学-信息与通信工程] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 0817[工学-化学工程与技术] 08[工学] 0804[工学-仪器科学与技术] 0703[理学-化学] 0803[工学-光学工程] 

基　　金：The authors would like to thank the Chemistry Discipline  Khulna University  Bangladesh  for their support. The funding provided by the Research and Innovation Centre (RIC)  Khulna University (No. KU/RIC/GUK/Cell/04/2000-272) has been recognized 

主　　题：Crystallite size 

摘      要：Herein, Na2EDTA-capped AuNPs specifically designed for selective smartphone-assisted colorimetric detection are synthesized and characterized. Na2EDTA-capped AuNPs was synthesized and characterized by UV–Visible spectroscopy, ATR, Raman, XRD, SEM and EDX. The calculated activation energy of the produced nanoparticles was 0.2 eV. Using XRD and SEM, the average crystallite size was found to be approximately 25 nm. Only Pb2+ and Cd2+, among the following metal ions: Mg2+, K+, Ca2+, Co2+, Ni2+, Ba2+, Hg+, Bi2+, Pb2+, and Cd2+, caused the AuNa2EDTA solution s hue to shift from reddish in color to blue. Pb2+ and Cd2+ were distinguished using a Na2S solution. Cotton pad with AuNa2EDTA integrated served as the substrate for metal ion adsorption. The GIMP software-supported smartphone was used to implement the color contrast (R) method. In the 10–2000 μM range, a straight line represented the relationship between 1/R and Pb2+ ion concentrations, with a limit of detection (LOD) of 0.28 μM was revealed. Real water sample collected from Rupsa River, Khulna, Bangladesh was tested by the developed colorimetric method to be 80 μM of Pb2+ ion. Combining the prevalence of smartphones and the potential of nanotechnology, a cotton-pad based platform functionalized with AuNa2EDTA may be a ground-breaking method for the detection of Pb2+ ions in various media. © 2025 Elsevier Ltd