• Development of Universal Biosensing Platforms Based on CRISPR/Cas12a systems

      Li, Yongya; Department of Chemistry
      CRISPR/Cas technologies possess the promising potential to affect biosensing field by providing a sensitive, precise, rapid, versatile and cost-effective method for diverse target detections. This thesis focusses on the development of CRISP/Cas12a based biosensing platforms for nucleic acid and protein detection. Two distinct CRISPR/Cas based diagnostic methods were developed. The first developed method is a plasmonic CRISPR Cas12a assay for colorimetric detection of viral nucleic acid. This assay generates colorimetric signals for nucleic acid amplicons by combining the unique target-induced collateral cleavage activity of Cas12a with plasmon coupling of DNA functionalized gold nanoparticles. The practical applications of this assay were successfully demonstrated through the nucleic acid detection of hepatitis B virus (HBV) and Grapevine Red-Blotch Virus (GRBV). The second developed method is a universal proximity CRISPR Cas12a assay for ultrasensitive detection of nucleic acids and proteins. The target recognition is achieved through proximity binding rather than direct CRISPR/Cas 12a recognition, allows the flexible assay design and expansion to target diverse targets. This assay was successfully adapted to detect nucleic acids and antibodies in both buffer and diluted human serum.