Abstract:
In this work, a paper-based analytical device (PAD) based on colorimetric assay using pyrrolidinyl peptide nucleic acid (acpcPNA) probe was developed as a sensor for the detection of Human papillomavirus (HPV) DNA. Dextrin-stabilized gold nanoparticles (d-AuNPs) was employed as a colorimetric reagent. The aggregation of d-AuNPs can be induced by positively charged acpcPNA generating a distinctive color change. After the hybridization of acpcPNA and DNA target, the residual acpcPNA probe can cause different degrees of the d-AuNPs aggregation, resulting in the detectable color change. The different color change before and after the introduction of the DNA target as a function of DNA concentration was quantified by analyzing the color intensity through a smartphone application. Under the optimal conditions, the linearity in the range from 1 to 1000 nM with a correlation coefficient of 0.9996 and an experimental limit of detection of 1 nM was obtained. In addition, the acpcPNA probe exhibited high selectivity for the target DNA over single-base-mismatch, two-base-mismatch, and non-complementary DNA. The proposed smartphone-based colorimetric DNA sensor offers a simple, sensitive, and selective platform for detecting HPV DNA. Therefore, this DNA sensing device can be utilized as an alternative tool for point-of-care and economical screening of HPV that is a major cause of cervical cancer.
