An electrochemical signal-on apta-cyto-sensor for quantitation of circulating human MDA-MB-231 breast cancer cells by transduction of electro-deposited non-spherical nanoparticles of gold

摘要

A highly simple, sensitive, specific and low-cost electrochemical apta-cyto-sensor for determination of circulating human MDA-MB-231 breast cancer cells was fabricated. Non-spherical nanoparticles of gold were electro-deposited in the presence of ethosuximide as a shape directing and size controlling agent. The nanoparticles had dimensions ranging 50-150 nm, and covered the underlying surface with a roughness factor of 8.03. The Non-spherical nanoparticles were then employed as the apta-cyto-sensor transducer. A 83-mer DNA aptamer that is specific to capturing the cell surface proteins was immobilized on the transducer surface, and binding with the cells was followed using the ferro/ferricyanide redox marker. The aptamer was immobilized within similar to 200 min on the transducer surface. The cells were quantified with an equation of regression of Delta Ip(mu A) = (1.028 +/- 0.027) log (C (cell mL(-1))) + (0.2199 +/- 0.0944), a sensitivity of 1.028 mu A (log (concentration / cell rnL(-1)))(-1) and a quantitation limit of 2 cell mL(-1), in a concentration range of 5 to 2 x 10(6) cell mL(-1). The apta-cyto-sensor selectivity was also evaluated toward AsPC-1, Calu-6, HeLa, MCF-7 and melanoma B16/F10 cell lines. The apta-cyto-sensor had a fabrication reproducibility of 4.2%, regeneration capability of 5.1%, a stability of 35 days, and a potential application for the detection of MDA-MB-231 cells in the spiked blood serum samples with a sensitivity of 0.8975 mu A (log (concentration / cell mL(-1)))(-1) and a quantitation limit of 5 cell mL(-1), in a concentration range of 10 to 1 x 10( 3) cell mL(-1). The apta-cyto-sensor would be applicable for breast cancer diagnosis at early stage. (C) 2019 Published by Elsevier B.V.