Impedimetric sensing platform for human papillomavirus and p53 tumor suppressor gene in cervical samples

Abstract

The oncogenic human papillomavirus (HPV) is an excellent biomarker for cervical cancer screening. The present research reports the construction of an integrated sensor platform (biosensorMY11 and biosensorp53) for the impedimetric detection of the HPV L1 sequence and p53 tumor suppressor gene. The nanostructured biosensor is composed of electrosynthesized polypyrrole (PPy) and gold nanoparticles (AuNPs). Methodological strategies based on cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), and atomic force microscopy (AFM) were used. The exposure of the genetic biosensors to molecular targets triggered changes in the analytical signals. Calibration plots for the biosensorMY11 showed a linear range between 0.001 to 100 pg μL−1 for all analyzed genotypes (HPV6, 11, 16, 18, 45, 53, 54, and 58). The detection limits were measured between 0.11 to 0.61 pg μL−1 and limits of quantification between 0.33 to 1.86 pg μL−1. The sensors exhibited reproducibility with a relative standard deviation of 4.21% and high repeatability (less than 2.5%). Two electrochemical profiles were obtained for high and low-risk HPV groups, suggesting the differential diagnosis using a degenerate oligonucleotide probe. Our results allow correlating the p53 gene expression in clinical samples infected with papillomavirus. The proposed biosensor represents an innovative device for the integrated monitoring of biomarkers related to cervical cancer with ultra-sensitive analytical performance.

Keywords

• Biosensor
• Cervical cancer
• Electrochemical impedance
• HPV
• Polypyrrole
• p53 gene