Rapid and quantitative detection of C-reactive protein based on quantum dots and immunofiltration assay

Rapid and quantitative detection of C-reactive protein based on quantum dots and immunofiltration assay

Blog Article

Pengfei Zhang,1,* Yan Bao,1,* Mohamed Shehata Draz,2,3,* Huiqi Lu,1 Chang Liu,1 Huanxing Han11Center for Translational Screen Protectors Medicine, Changzheng Hospital, Second Military Medical University, Shanghai, People’s Republic of China; 2Zhejiang-California International Nanosystems Institute, Zhejiang University, Hangzhou, Zhejiang, People’s Republic of China; 3Faculty of Science, Tanta University, Tanta, Egypt*These authors contributed equally to this workAbstract: Convenient and rapid immunofiltration assays (IFAs) enable on-site “yes” or “no” determination of disease markers.However, traditional IFAs are commonly qualitative or semi-quantitative and are very limited for the efficient testing of samples in field diagnostics.Here, we overcome these limitations by developing a quantum dots (QDs)-based fluorescent IFA for the quantitative detection of C-reactive proteins (CRP).CRP, the well-known diagnostic marker for acute viral and bacterial infections, was used as a model analyte to demonstrate performance and sensitivity of our developed QDs-based One Piece IFA.

QDs capped with both polyethylene glycol (PEG) and glutathione were used as fluorescent labels for our IFAs.The presence of the surface PEG layer, which reduced the non-specific protein interactions, in conjunction with the inherent optical properties of QDs, resulted in lower background signal, increased sensitivity, and ability to detect CRP down to 0.79 mg/L with only 5 µL serum sample.In addition, the developed assay is simple, fast and can quantitatively detect CRP with a detection limit up to 200 mg/L.

Clinical test results of our QD-based IFA are well correlated with the traditional latex enhance immune-agglutination aggregation.The proposed QD-based fluorescent IFA is very promising, and potentially will be adopted for multiplexed immunoassay and in field point-of-care test.Keywords: C-reactive proteins, point-of-care test, Glutathione capped QDs, PEGylation.