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

Abstract

The concentration of wild-type tumour suppressor p53wt 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 p53wt 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 p53wt 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 p53wt concentration was established as limit of detection. This work paves the way for fast and highly sensitive tools for p53wt detection in physiological fluids, which deserve much interest in early cancer diagnosis and prognosis.

Recent Advances of Field-Effect Transistor Technology for Infectious Diseases

“…Extended gate Chem/BioFETs have been designed to improve these deficiencies, which are investigated in literature with different applications for pH measurement of ion solutions and other bio-interfaces [ 16 ]. In comparison with ISFETs, extended gate FETs have shown much better stability in terms of chemical, thermal and incident light disturbances in parallel with greater sensitivity [ 16 , 77 ]. Figure 9 demonstrates an example of an extended gate FET sensor that has been used as a platform for biochemical analysis [ 76 ]…”

“…A complete review of these sensors is done in other work by Pullano et al [ 75 ]. An extended gate sensor was used for direct potentiometric serological diagnosis toward detection of Bovine Herpes Virus-1 (BHV-1) pathogen by Tarasov et al [ 77 ]. Their design has been shown in Figure 10 , which demonstrates an extended gate connected to the gate of a MOSFET.…”

Preparation and Characterization of Au/NiPc/Anti-p53/BSA Electrode for Application as a p53 Antigen Sensor

“…Additionally, both the preparation process and the protein detection time were faster than the previously reported biochemical method [14]. The clinically significant cut-off levels for the detection of the p53 protein in the published literature are 90 pg/mL for ovarian cancer [36], 60 pg/mL for oral squamous cell carcinomas [37], 50 pg/mL for lung cancer [38] and Hodgkin lymphoma [35], 30 pg/mL for malignant lymphoma [38], and 10 pg/mL for small-cell lung [38]. Consequently, both the Au/NiPc/anti-p53 (1 ng/mL)/BSA and Au/NiPc/anti-p53 (100 ng/mL)/BSA electrodes successfully met the detection needs of p53 in these solid malignancies.…”

Exploration of Ion Sensitive Field-Effect Transistor With Dielectric Properties

“…The existing CMOS fabrication process offers the advantage of miniaturizing and concurrent sensing. Different biological analytes have experimented with for the detection of viruses including COVID-19, In uenza, and Hepatitis-B, etc, besides it also uses for designing nucleic acid sensors depends on DNA hybridization [15]. The advantage of the ISFET sensor emerges in speed, sensitivity, speci city which is the primary requirement of COVID-19 detection presented in [16].…”