A Portable Smart-Phone Readout Device for the Detection of Mercury Contamination Based on an Aptamer-Assay Nanosensor

• Published in: Sensors (Basel, Switzerland) Vol. 16; no. 11; p. 1871
• Main Authors: Xiao, Wei, Xiao, Meng, Fu, Qiangqiang, Yu, Shiting, Shen, Haicong, Bian, Hongfen, Tang, Yong
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 08-11-2016; MDPI
• Subjects: Assaying; colorimetric aptamer nanosensor; Colorimetry; Colorimetry - methods; Contamination; Drinking water; Gold; gold nanoparticle; Limit of Detection; Mercury; Mercury - analysis; mercury ions; Metal Nanoparticles - chemistry; microwell reader; Nanosensors; Photometers; Portable equipment; Signal processing; Smartphone; Smartphones; Water Pollutants, Chemical - analysis; microwell reader; colorimetric aptamer nanosensor; smartphone; gold nanoparticle; mercury ions
• ISSN: 1424-8220; 1424-8220
• DOI: 10.3390/s16111871

The detection of environmental mercury (Hg) contamination requires complex and expensive instruments and professional technicians. We present a simple, sensitive, and portable Hg
detection system based on a smartphone and colorimetric aptamer nanosensor. A smartphone equipped with a light meter app was used to detect, record, and process signals from a smartphone-based microwell reader (MR S-phone), which is composed of a simple light source and a miniaturized assay platform. The colorimetric readout of the aptamer nanosensor is based on a specific interaction between the selected aptamer and Hg
, which leads to a color change in the reaction solution due to an aggregation of gold nanoparticles (AuNPs). The MR S-phone-based AuNPs-aptamer colorimetric sensor system could reliably detect Hg
in both tap water and Pearl River water samples and produced a linear colorimetric readout of Hg
concentration in the range of 1 ng/mL-32 ng/mL with a correlation of 0.991, and a limit of detection (LOD) of 0.28 ng/mL for Hg
. The detection could be quickly completed in only 20 min. Our novel mercury detection assay is simple, rapid, and sensitive, and it provides new strategies for the on-site detection of mercury contamination in any environment.