title: Ultrasensitive colorimetric assay of cadmium ion based on silver nanoparticles functionalized with 5-sulfosalicylic acid for wide practical applications.
abstract: Low-level cadmium ion (Cd(2+)) exposure contributes much toward the causation of chronic disease. Due to its low permissible exposure limit, overexposures may occur even in situations where trace quantities of Cd(2+) exist. So far, no effective treatment for Cd(2+) toxicity has been reported. Prevention of further exposure is the most important step in management of patients suggestive of Cd(2+) intoxication. Development of sensors for Cd(2+) is of great interest to ensure early diagnosis and improve management. We propose here a simple, low-cost (0.1$ per sample) yet very sensitive (limit of detection is 3.0 nM) and selective colorimetric assay for rapid (2 min) determination of Cd(2+) based on 5-sulfosalicylic acid functionalized silver nanoparticles (SAA-AgNPs). This method shows excellent selectivity for Cd(2+) over the other 16 metal ions. It is also precise and highly reproducible in determining Cd(2+) in real samples such as tap water, milk, serum, and urine with recoveries ranging from 93 to 110%, indicating the wide practical application to samples suspected of Cd(2+) exposure.
authors.affiliation: Department of Chemistry, Nanchang University, Nanchang 330031, China. fywu@ncu.edu.cn lihua2003@gmail.com.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Jin
authors.forename: Pengcheng
authors.initials: P
authors.lastname: Huang
authors.forename: Fangying
authors.initials: F
authors.lastname: Wu
authors.forename: Li-Hua
authors.initials: LH
authors.lastname: Ma
mesh_terms: D001557:Benzenesulfonates / Q000737:chemistry*; D002104:Cadmium / Q000032:analysis*; D003124:Colorimetry / Q000379:methods*; D004785:Environmental Pollutants / Q000032:analysis*; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry*; D012459:Salicylates / Q000737:chemistry*; D012834:Silver / Q000737:chemistry*
chemical_list: D001557:Benzenesulfonates; D004785:Environmental Pollutants; D012459:Salicylates; D002104:Cadmium; D012834:Silver; C003366:sulfosalicylic acid