Tuning CdTe quantum dots reactivity for multipoint detection of mercury (II), silver(I) and copper(II)

• Type: Article in International Scientific Journal
• Date: 2019

Authors

Ribeiro, DSM (Author) Other; Castro, RC (Author) Other; Pascoa, RNMJ (Author) Other; Jose X Soares (Author) FFUP; Rodrigues, SSM (Author) Other; Joao L M Santos (Author) FFUP

Journal

Title: Journal of Luminescence

Vol. 207

Pages: 386-396

ISSN: 0022-2313

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 0 Citations

Scopus - 10 Citations

Other information

Authenticus ID: P-00Q-2YT

DOI: 10.1016/j.jlumin.2018.11.035

Abstract (EN): In this work we tuned the surface chemistry of distinctly-sized CdTe quantum dots (QDs), by using a variety of capping ligands with distinctive functional moieties, and combined them in multi-QDs probing solutions for Hg-2(+), Cu-2(+) and Ag+. Upon the individual interaction of the distinctly-capped QDs with each of the above-mentioned metal ions, several parameters such as Stern-Volmer constants, equilibrium binding constants, the red-shift magnitude and photoluminescence (PL) lifetime values were thoroughly evaluated. Due to their great reactivity, selectivity could become a major issue in the application of semiconductor quantum dots in chemical analysis. Therefore, the combination in the same analysis of multiple QDs, capped with distinct ligands and emitting at different wavelengths, was exploited to guarantee a specific analyte-response profile. When coupled with chemometrics, for data analysis and processing, the developed approach provided enhanced selectivity and accuracy. In fact, the obtained results of all the partial least squares (PLS) models coefficient of determination of cross-validation (R-CV(2)) close to 1, root mean square error of calibration (RMSEC) and root mean square error of cross-validation (RMSECV) values ranging 0.0094-0.15 and 0.013-0.19 mg L-1, respectively. demonstrated the possibility to perform accurate predictions of Hg-2(+) and Cu-2(+). Additionally, the sensitivity of the developed models was also calculated and allowed us to conclude which combination of distinctly-capped QDs assured a more sensitive quantification of Cu-2(+) (sensitivity = 653 L-1 mg for 3-mercaptopropionic acid (MPA)/MPA conjugated probe) and Hg-2(+) (sensitivity = 14,017 L-1 mg for reduced glutathione (GSH)/MPA-conjugated probe).

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 11