Magnetic particle-based immunoassay of phosphorylated p53 using protein cage templated lead phosphate and carbon nanospheres for signal amplification
| Autor: | Xiaoxiao Ge, Aiqiong Chen, Yuehe Lin, Yuanwu Bao, Dan Du, Yongsoon Shin |
|---|---|
| Rok vydání: | 2012 |
| Předmět: |
Detection limit
Chromatography biology medicine.diagnostic_test Chemistry General Chemical Engineering Metal ions in aqueous solution Nanoparticle General Chemistry Magnetic particle inspection Primary and secondary antibodies Metal visual_art Immunoassay Electrode visual_art.visual_art_medium biology.protein medicine |
| Zdroj: | RSC Advances. 2:11029 |
| ISSN: | 2046-2069 |
| DOI: | 10.1039/c2ra20994b |
| Popis: | Phosphorylated p53 at serine 15 (phospho-p5315) is a potential biomarker of gamma-radiation exposure. In this paper, we described a new magnetic particle (MP)-based electrochemical immunoassay of human phospho-p5315 using carbon nanospheres (NS) and protein cage nanoparticles (PCN) for signal amplification. Greatly enhanced sensitivity was achieved for three reasons: 1) PCN and the p5315 signal antibody (p5315 Ab2) are linked to the carbon NS (PCN-p5315 Ab2-NS) as a label; 2) PCN increases the amount of metal ions in the cavity of each apoferritin; 3) MPs capture a large amount of primary antibodies. Protein cage templated metallic phosphates, instead of enzymes, as multi-labels have the advantage of eliminating the addition of mediator or immunoreagents and, thus, makes the immunoassay system simpler. Subsequent stripping voltametric analysis, detected olead ions on a disposable screen-printed electrode. The response current was proportional to the phospho-p5315 concentration in the range of 0.02 to 20 ng mL−1 with a detection limit of 0.01 ng mL−1, which was 30-fold lower than that of the ELISA measurement of phospho-p5315. This method shows an acceptable stability and reproducibility and the assay results for phospho-p5315-spiked human serum presented good recovery rates. |
| Databáze: | OpenAIRE |
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