Smart NIR light-gated CRISPR/Cas12a fluorescent biosensor with boosted biological delivery and trans-cleavage activity for high-performance in vivo operation.

Despite the in vitro usage of CRISPR/Cas12a system in fluorescent biosensors has made remarkable achievements, many challenges such as poor biological delivery, insufficient sensitivity, and uncontrollable initiation compel them hard to conduct in vivo analysis. Thus, we propose here some fruitful sensing concepts. First, the multiple biomolecular components of CRISPR/Cas12a system are collectively carried by MnO nanosheets via a simple physical absorption to achieve a highly-efficient biological uptake. Under the reduction of widespread biothiols, not only the sensing frame is easily released but also sufficient Mn is produced to serve as an effective trans-cleavage accelerator. Furthermore, a photocleavge-linker induced smart near-infrared (NIR) light-gated manner is designed to offer a spatiotemporal target recognition, for which a 808 nm NIR light transduced ultraviolet upconversion luminescence with weak thermal effect is employed to completely prevent the sensing flow from pre-initiating during the biological delivery. As a conceptual validation, this biosensor has satisfactory sensitivity and specificity to survivn messenger RNA (a broad-spectrum cancer biomarker). More importantly, it can work as a reliable imaging platform for differentiating cancers in live cellular level and also presents a high-performance operation ability for analyzing live mice, greatly promoting the CRISPR technology in biosensing field.