Unusual Selective Response to Glycoprotein over Sugar Facilitates Ultrafast Universal Fluorescent Immunoassay of Biomarkers.
Yi-Ting WangNa WuTing YangJian-Hua WangPublished in: Analytical chemistry (2020)
The enzyme-linked immunosorbent assay (ELISA) is widely used in clinical diagnostics. However, conventional ELISA is labor-intensive and lengthy. Herein, the sensitive detection of biomarkers with only one-step incubation of 20 min is demonstrated, based on antibody-fused, boronic-acid-decorated carbon nitride nanosheets. The decoration of carbon nitride nanosheets with boronic acid facilitates antibody binding at physiological conditions along with a concomitant fluorescence enhancement. The presence of target antigen results in a decrement of the fluorescence and ensures one-step immunofluorescent detection. The immune recognition of the antibody/target antigen in combination with glucose blocking ensures a highly selective assay of the biomarkers. The protocol is validated by the assay of nonglycoprotein, glycoprotein, and small-molecular-toxin targets. The multiplex target detection capability is demonstrated by the simultaneous assay of the triple cardiac biomarker cTnI, Mb, and CK-MB in human serum.
Keyphrases
- quantum dots
- sensitive detection
- energy transfer
- loop mediated isothermal amplification
- high throughput
- reduced graphene oxide
- label free
- real time pcr
- single molecule
- escherichia coli
- visible light
- highly efficient
- gold nanoparticles
- skeletal muscle
- single cell
- blood pressure
- adipose tissue
- metal organic framework
- binding protein
- dna binding