The point-of-care-testing of nucleic acids by chip, cartridge and paper sensors

Point-of-care nucleic acid testing(POCNAT) has played an important role in the outbreak of infectious diseases(e.g., COVID-19) over recent years. POCNAT aims to realize the rapid, simple and automatic detection of nucleic acid. Thanks to the development of manufacturing technology, electronic information technology, artificial intelligence technology, and biological information technology in recent years, the development of the POCNAT device has led to significant advancement. Instead of the normal nucleic acid detection methods used in the laboratory, some novel experimental carriers have been applied, such as chips, cartridges and papers. The application of these experimental carriers has realized the automation and integration of nucleic acid detection. The entire process of nucleic acid detection is normally divided into three steps(nucleic acid extraction, target amplification and signal detection). All of the reagents required by the process can be pre-stored on these experimental carriers, without unnecessary manual operation. Furthermore, all of the processes are carried out in this experimental carrier, with the assistance of a specific control device. Although they are complicated to manufacture and precise in design,their application provides a significant step forwards in nucleic acid detection and realizes the integration of nucleic acid detection. This technology has great potential in the field of point-of-care molecular diagnostics in the future. This paper focuses on the relevant content of these experimental carriers.

Rapid identification of diarrheagenic Escherichia coli based on barcoded magnetic bead hybridization

Diarrhea,as a global public health problem,causes a large number of infections and deaths every year.Although Escherichia coli(E.coli)is one of the normal flo ra microorganisms in the human intestinal tract,it has five pathogenic bacteria types that can cause human diarrhea,known as diarrheagenic E.coli.When people are infected,rapid and accurate diagnosis,along with timely treatment,are especially important.Here,we introduce a new method to identify and analyze a large number of pathogenic strains in E.coli by multiplex PCR and barcoded magnetic bead hybridization.Results show that the detection sensitivities of enterohemorrhagic E.coli,enterotoxigenic E.coli,enteropathogenic E.coli,enteroinvasive E.coli and enteroaggregative E.coli were 1.3×10^3 CFU/mL,2×10^4 CFU/mL,4×10^4 CFU/mL,7.2×10^4 CFU/mL and 1.7 CFU/mL respectively.This method has strong specificity and high sensitivity and detects multiple target sequences in one experiment.Compared with other methods,BMB array has great application potential.