Abstract
Urgent identification of COVID-19 in infected patients is highly important nowadays. Förster or fluorescence resonance energy transfer (FRET) is a powerful and sensitive method for nanosensing applications, and quantum dots are essential materials in FRET-based nanosensors. The QDs are conjugated to DNA or RNA and used in many applications. Therefore, in the present study, novel fluorescence DNA-conjugated CdTe/ZnS quantum dots nanoprobe designed for detection of Covid-19 after extracting their RNA from saliva of hesitant people. For achieving this purpose, the water-soluble CdTe/ZnS QDs-DNA prepared via replacing the thioglycolic acid (TGA) on the surface of QDs with capture DNA (thiolated DNA) throw a ligand-exchange method. Subsequently, by adding the different concentrations of complementary (target DNA) in a mixture of quencher DNA (BHQ 2 -labeled DNA) and the QDs-DNA conjugates at different conditions, sandwiched hybrids were formed. The results showed that the fluorescence intensity was decreased with increasing the concentration of target DNA (as a positive control). The linear equation and regression (Y = 40.302 X + 1 and R 2 = 0.98) were obtained by using the Stern-Volmer relationship. The Limit of detection (LOD) was determined 0.000823 µM. The achieved results well confirm the outcomes of the RT-PCR method in real samples.
Keywords: CdTe/ZnS quantum dots; Complementary DNA; Covide-19 virus; FRET; Nanosensor.
【저자키워드】 FRET, CdTe/ZnS quantum dots, Complementary DNA, Covide-19 virus, Nanosensor., 【초록키워드】 COVID-19, Saliva, outcome, RT-PCR, RNA, DNA, Complementary DNA, Concentration, Regression, complementary, energy transfer, infected patients, mixture, positive control, conjugate, fluorescence intensity, linear equation, Nanosensor, thioglycolic acid, linear, was determined, infected patient, conditions, R 2, replacing, 【제목키워드】 COVID-19,