Computational and dark-field ghost imaging with ultraviolet light

Ultraviolet(UV)imaging enables a diverse array of applications,such as material composition analysis,biological fluorescence imaging,and detecting defects in semiconductor manufacturing.However,scientific-grade UV cameras with high quantum efficiency are expensive and include complex thermoelectric cooling systems.Here,we demonstrate a UV computational ghost imaging(UV-CGI)method to provide a cost-effective UV imaging and detection strategy.By applying spatial–temporal illumination patterns and using a 325 nm laser source,a singlepixel detector is enough to reconstruct the images of objects.We use UV-CGI to distinguish four UV-sensitive sunscreen areas with different densities on a sample.Furthermore,we demonstrate dark-field UV-CGI in both transmission and reflection schemes.By only collecting the scattered light from objects,we can detect the edges of pure phase objects and small scratches on a compact disc.Our results showcase a feasible low-cost solution for nondestructive UV imaging and detection.By combining it with other imaging techniques,such as hyperspectral imaging or time-resolved imaging,a compact and versatile UV computational imaging platform may be realized for future applications.

Single-molecule RNA capture-assisted droplet digital loop-mediated isothermal amplification for ultrasensitive and rapid detection of infectious pathogens

To minimize and control the transmission of infectious diseases,a sensitive,accurate,rapid,and robust assay strategy for application on-site screening is critical.Here,we report single-molecule RNA capture-assisted digital RT-LAMP(SCADL)for point-of-care testing of infectious diseases.Target RNA was captured and enriched by specific capture probes and oligonucleotide probes conjugated to magnetic beads,replacing laborious RNA extraction.Droplet generation,amplification,and the recording of results are all integrated on a microfluidic chip.In assaying commercial standard samples,quantitative results precisely corresponded to the actual concentration of samples.This method provides a limit of detection of 10 copies mL−1 for the N gene within 1 h,greatly reducing the need for skilled personnel and precision instruments.The ultrasensitivity,specificity,portability,rapidity and user-friendliness make SCADL a competitive candidate for the on-site screening of infectious diseases.