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文獻名： Photoluminescent nanoprobes based on thiols capped CdTe quantum dots for direct determination of thimerosal in vaccines

 

 

作者： Amidou Tall^ab,  Karolayne Rochada Costa^b,  Maria Janaínade Oliveira^b,  IssaTapsoba^a,  Uéslen Rocha^c,  Tasso O. Sales^c,  Marília Oliveira Fonseca Goulart^b,  Josué Carinhanha Caldas Santos^b

^a Laboratory of Analytical, Environmental and Bio-Organic Chemistry, Chemistry Department, University Joseph KI ZERBO, 03 BP 7021 Ouagadougou 03, Ouagadougou, Burkina Faso

^b Institute of Chemistry and Biotechnology, Federal University of Alagoas, Campus A.C. Simões, 57072-900, Maceió, Alagoas, Brazil

^c Institute of Physics, Federal University of Alagoas, Campus A.C. Simões, 57072-900, Maceió, Alagoas, Brazil

 

 

 

摘要：CdTe quantum dots (CdTe QD) have been produced at different times of synthesis (1, 2, and 4 h) using thiols as capping agents: mercaptopropionic acid (MPA), mercaptosuccinic acid (MSA) and N-acetyl-l-cysteine (NAC) using water as a solvent. The produced CdTe QD were characterized by UV–vis and photoluminescence (PL) spectroscopy and showed a relationship among reflux time, size, and spectroscopic properties. CdTe QD were shown to interact with thimerosal (TM), an organic mercury compound, and the PL intensity was effectively quenched, characterizing an ON-OFF process. However, the NAC capped CdTe (CdTe-NAC) at 1 h presented the best sensitivity for TM determination. Under optimized conditions, a linear range from 0.1 to 1.0 μg mL⁻¹ (0.25–2.5 μM) and a LOD of 26.6 μg L⁻¹ (66.7 nM) were achieved. The influence of different mercuric species [Hg(II), methylmercury, ethylmercury, and phenylmercury], along with thiosalicylic acid (TSA), and other ionic species on the sensitivity of the method and the interaction mechanism between TM and CdTe-NAC have been discussed. The method was successfully applied for direct quantification of TM in vaccines, and the results were validated by cold vapor atomic fluorescence spectroscopy (CV AFS). Finally, the proposed method proved to be fast, sensitive, and simple for suitable use in vaccine quality control.

 

關鍵詞：Thimerosal; Nanoparticles; Photoluminescence quenching; Sensing; Immunogens