Programmable DNA Nanoswitch-Regulated Plasmonic CRISPR/Cas12a-Gold Nanostars Reporter Platform for Nucleic Acid and Non-Nucleic Acid Biomarker Analysis Assisted by a Spatial Confinement Effect.

CRISPR/Cas 12a system based nucleic acid and non-nucleic acid targets detection faces two challenges including (1) multiple crRNAs are needed for multiple biomarkers detection and (2) insufficient sensitivity resulted from photobleaching of fluorescent dyes and the low kinetic cleavage rate for a traditional single-strand (ssDNA) reporter. To address these limitations, we developed a programmable DNA nanoswitch (NS)-regulated plasmonic CRISPR/Cas12a-gold nanostars (Au NSTs) reporter platform for detection of nucleic acid and non-nucleic acid biomarkers with the assistance of the spatial confinement effect. Through simply programming the target recognition sequence in NS, only one crRNA is required to detect both nucleic acid and non-nucleic acid biomarkers. The detection limit decreased by ∼196-fold for miRNA-375 and 122-fold for prostate-specific antigen (PSA), respectively. Moreover, versatile evaluation of miRNA-375 and PSA in clinical urine samples can also be achieved, according to which prostate cancer and healthy groups can be well identified.