Dual gold nanoparticles-enhanced sensitivity of colorimetric immunoassay for the visual detection of cervical cancer biomarker

W. Maneeprakorn, N. Apiwat, S. Tapaneeyakorn, T. Dharakul
National Nanotechnology Center, National Science and Technology Development Agency, TH

Keywords: cervical cancer biomarker, gold nanoparticles, colorimetric immunoassay

Summary:

The gold nanoparticle (AuNP) based lateral flow immunochromatographic assay (LFA) is simple, rapid, and inexpensive for diagnostic applications. For cervical cancer screening, LFA can be considered as alternative to the Papanicolaou test or PAP smears for its ease of use and low-cost. However, compared with other immunoassays, the detection sensitivity of the AuNP-based LFA is very low. This work reported the development of enhanced sensitivity LFA using dual AuNPs for detection of P16 which is a tumor suppressor protein over-expressed in precancerous stage of cervical cancer. Two different sizes of AuNP-antibody conjugate were prepared and applied to the assay. The mechanism of the LFA is based on antigen-antibody interaction. The percentage of B-BSA immobilized on 1st conjugate and the utilized ratio between 1st and 2nd conjugate were optimized. The detection sensitivity of the enhanced sensitivity LFA increased about 100-fold compared with conventional LFA. With this method, approximately 0.1 µg/mL of P16 can be detected within 15 minutes and was highly reproducible. The results indicated that the assay can facilitate the early and rapid method for cervical cancer diagnosis. Such a simple immunoassay holds great potential as sensitive, selective and point-of-care (POC) tool for clinical diagnosis of cervical cancer.