Open AccessThis article is
- freely available
Colorimetric Assay for Determination of Lead (II) Based on Its Incorporation into Gold Nanoparticles during Their Synthesis
College of Chemistry and Chemical Engineering, Graduate University of Chinese Academy of Sciences, 19A YuQuan Road, Beijing 100049, China
State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100191, China
Huaihua Medical College, Hunan, 418000, China
Medical College, Hunan Normal University, Changsha, Hunan 410006, China
* Authors to whom correspondence should be addressed.
Received: 10 October 2010; in revised form: 15 November 2010 / Accepted: 2 December 2010 / Published: 7 December 2010
Abstract: In this report, we present a new method for visual detection of Pb2+. Gold nanoparticles (Au-NPs) were synthesized in one step at room temperature, using gallic acid (GA) as reducer and stabilizer. Pb2+ is added during the gold nanoparticle formation. Analysis of Pb2+ is conducted by a dual strategy, namely, colorimetry and spectrometry. During Au-NPs synthesis, addition of Pb2+ would lead to formation of Pb-GA complex, which can induce the aggregation of newly-formed small unstable gold nanoclusters. Consequently, colorimetric detection of trace Pb2+ can be realized. As the Pb2+ concentration increases, the color turns from red-wine to purple, and finally blue. This method offers a sensitive linear correlation between the shift of the absorption band (Δλ) and logarithm of Pb2+ concentration ranging from 5.0 × 10−8 to 1.0 × 10−6 M with a linear fit coefficient of 0.998, and a high selectivity for Pb2+ detection with a low detection limit down to 2.5 × 10−8 M.
Keywords: visual detection; lead ions; gold nanoparticles; gallic acid
Article StatisticsClick here to load and display the download statistics.
Notes: Multiple requests from the same IP address are counted as one view.
Cite This Article
MDPI and ACS Style
Ding, N.; Cao, Q.; Zhao, H.; Yang, Y.; Zeng, L.; He, Y.; Xiang, K.; Wang, G. Colorimetric Assay for Determination of Lead (II) Based on Its Incorporation into Gold Nanoparticles during Their Synthesis. Sensors 2010, 10, 11144-11155.
Ding N, Cao Q, Zhao H, Yang Y, Zeng L, He Y, Xiang K, Wang G. Colorimetric Assay for Determination of Lead (II) Based on Its Incorporation into Gold Nanoparticles during Their Synthesis. Sensors. 2010; 10(12):11144-11155.
Ding, Nan; Cao, Qian; Zhao, Hong; Yang, Yimin; Zeng, Lixi; He, Yujian; Xiang, Kaixiang; Wang, Guangwei. 2010. "Colorimetric Assay for Determination of Lead (II) Based on Its Incorporation into Gold Nanoparticles during Their Synthesis." Sensors 10, no. 12: 11144-11155.