Electrochemical determination of caspase-3 using signal amplification by HeLa cells modified with silver nanoparticles.
Daohong WuYuhan HeLiujuan TongJianxiu WangLin LiuXinyao YiShengqiang HuPublished in: Mikrochimica acta (2021)
An electrochemical sensor capable of quantitative determination of caspase-3 activities was developed. A thiolated peptide whose sequence contained a caspase-3 cleaved site and a cell penetration sequence was preimmobilized onto an electrode. The quantification of caspase-3 was accomplished after cell penetration and the subsequent adsorption of silver nanoparticles (AgNPs). The oxidation current of AgNPs was found to be inversely proportional to the concentration of caspase-3 between 0.02 and 0.2 U/mL. A detection limit of 0.02 U/mL for caspase-3 was achieved due to the large number of positively charged AgNPs adsorbed onto the negatively charged cells. The proof of concept was demonstrated by monitoring the cleavage of surface-confined peptide substrates by caspase-3 in cell lysates. The current sensor could be extended to detect cells by replacing the surface-confined peptide with aptamers that recognize cells. Thus, the use of a cell as a matrix for AgNPs shows excellent potential for constructing electrochemical sensors and provides a useful alternative for sensor development in the future. Cells modified with silver nanoparticles were utilized as the electrochemical readout of an electrochemical assay.
Keyphrases
- induced apoptosis
- silver nanoparticles
- endoplasmic reticulum stress
- cell cycle arrest
- cell death
- signaling pathway
- oxidative stress
- gold nanoparticles
- molecularly imprinted
- label free
- ionic liquid
- cell therapy
- nitric oxide
- mesenchymal stem cells
- high throughput
- cell proliferation
- high resolution
- stem cells
- solid phase extraction
- electron transfer
- hydrogen peroxide
- loop mediated isothermal amplification
- sensitive detection
- simultaneous determination