Optical DNA Based Sensors for Cervical Cancers

Optical biosensors are devices frequently used to detect different molecules in biological applications through their interaction with light. Optical biosensors have many advantages because they allow fast and direct detection of target molecules. So, they can be easily applied to different types of delicate or miniature point-of-care devices with high reliability. Although many different types of optical platforms are used in biosensing, fluorescent and colorimetric sensors have mostly been adapted for the detection of cervical cancer. Many studies are reporting rapid, low-cost, and disposable biosensors using fluorescently labeled probes with various fluorophores to detect human papillomavirus (HPV) DNA in a single assay. However, fluorescent biosensors can be adapted with nanoparticles, microbeads, and two-dimensional nanomaterials, and even Clustered regularly interspaced short palindromic repeats—CRISPR associated (CRISPR-Cas) for an improved limit of detection, easy separation of probes, simplification of sensor design and operation, etc. Similarly, many colorimetric sensors have been reported for the detection of different types of HPV DNA. Colorimetric sensors have a unique advantage as detection can be carried out with naked eyes without the need for any instrument but only has relatively moderate sensitivity. Additional techniques, such as loop-mediated isothermal amplification, DNAzymes, peptide nucleic acid, can be incorporated to improve its detection limit significantly. Besides, both fluorescence and colorimetric sensors can be applied to lateral flow assays, microfluidic systems, or microarrays for rapid and multiplexed detection of HPV. In this chapter, recent progress in the DNA-based optical biosensors for cervical cancer detection is summarized with emphasis on fluorescent and colorimetric sensors.