The Evaluation of Colorectal Cancer Risk in Serum by anti-DESMIN-conjugated CdTe/CdS Quantum Dots.

Yao Wang, Yuanting Li, Zhiyong Chen, Tianhao Wang, Jie Gu, Xianhua Wu, Yi Yin, Maosheng Wang, Zhigang Pan

Clinical laboratory 2017 Mar 01

filter terms:

DESMIN is a novel prognostic predictor and therapeutic target for colorectal cancer (CRC). Enzyme-linked immunosorbent assay (ELISA) and electrochemiluminescence (ELC) assays are large-scale and highcost projects; therefore, it is necessary to develop a new, fast, and simple yet highly sensitive and specific method to detect DESMIN in serum. Semiconducting quantum dots (QDs) possess high fluorescence quantum yield, stability against photobleaching, and size-controlled luminescence properties, thus being utilized in photoelectrochemical tumor marker detection, especially in ameliorating the diagnostic value in complex biological ambient ionization. However, CdTe/CdS quantum dots (QDs) have not been applied in detecting DESMIN in serum. DESMIN in serum has been established using anti-DESMIN-conjugated CdTe/CdS quantum dots (QDs) and measurements. The assay sensitivity was determined by measurement of quenched fluorescence intensity of DESMIN at 0.1, 0.5, 1.0, 2.0, or 5.0 ng/mL in PBS or 0.25%, 0.5%, 1.0%, 2.0%, or 5% human serum diluted in PBS. The assay was optimized under different pH (7.00 - 7.40) for different reaction durations (10 - 60 minutes). The specificity of anti-DESMIN-QDs was determined by testing the interference of DESMIN activity with CEA, IgG, or AFP, each at 1 ng/mL. Under the optimized incubation time (30 minutes) at room temperature and optimal pH 7.1 - 7.2, a correlation between the decreased fluorescence intensity of anti-DESMIN-conjugated CdTe/CdS QDs and the concentration of DESMIN in the range from 0.05 to 100 ng/mL, was established. The sensitivity for the detection of DESMIN in the range from 0.05 to 100 ng/mL, with a detection limit of 0.02 ng/mL. The assay presented a high specificity because the anti-DESMIN-conjugated CdTe/CdS QDs only reacted with ABR1B10 in the sera in the presence of CEA, IgG or AFP. The immunofluorescence assay to detect DESMIN in serum using anti-DEMSIN-conjugated CdTe/ CdS QDs was fast and simple yet presented high sensitivity and specificity. Our method provides a promising tool for early prediction of CRC risk.

Citation

Yao Wang, Yuanting Li, Zhiyong Chen, Tianhao Wang, Jie Gu, Xianhua Wu, Yi Yin, Maosheng Wang, Zhigang Pan. The Evaluation of Colorectal Cancer Risk in Serum by anti-DESMIN-conjugated CdTe/CdS Quantum Dots. Clinical laboratory. 2017 Mar 01;63(3):579-586