A Reliable BioFET Immunosensor for Detection of p53 Tumour Suppressor in Physiological-Like Environment

Sensors

Chiara Baldacchini¹  AntoninoFrancesco Montanarella¹  AnnaRita Bizzarri¹  Salvatore Cannistraro¹  MariaAssunta Signore²  Luca Francioso² 

[1] Biophysics and Nanoscience Centre, DEB, Università degli Studi della Tuscia, 01100 Viterbo, Italy;CNR-IMM Institute for Microelectronics and Microsystems, Via Monteroni, University Campus, Bld. A/3, 73100 Lecce, Italy;

关键词: p53;    EGFET;    immunosensors;    BioFET;   

DOI  :  10.3390/s20216364

来源: DOAJ

【 摘 要 】

The concentration of wild-type tumour suppressor p53_wt in cells and blood has a clinical significance for early diagnosis of some types of cancer. We developed a disposable, label-free, field-effect transistor-based immunosensor (BioFET), able to detect p53_wt in physiological buffer solutions, over a wide concentration range. Microfabricated, high-purity gold electrodes were used as single-use extended gates (EG), which avoid direct interaction between the transistor gate and the biological solution. Debye screening, which normally hampers target charge effect on the FET gate potential and, consequently, on the registered FET drain-source current, at physiological ionic strength, was overcome by incorporating a biomolecule-permeable polymer layer on the EG electrode surface. Determination of an unknown p53_wt concentration was obtained by calibrating the variation of the FET threshold voltage versus the target molecule concentration in buffer solution, with a sensitivity of 1.5 ± 0.2 mV/decade. The BioFET specificity was assessed by control experiments with proteins that may unspecifically bind at the EG surface, while 100pM p53_wt concentration was established as limit of detection. This work paves the way for fast and highly sensitive tools for p53_wt detection in physiological fluids, which deserve much interest in early cancer diagnosis and prognosis.

【 授权许可】

Unknown