Aptasensors for rapid detection of Escherichia coli O157:H7 and Salmonella typhimurium.

Herein we reported the development of aptamer-based biosensors (aptasensors) based on label-free aptamers and gold nanoparticles (AuNPs) for detection of Escherichia coli (E. coli) O157:H7 and Salmonella typhimurium. Target bacteria binding aptamers are adsorbed on the surface of unmodified AuNPs to capture target bacteria, and the detection was accomplished by target bacteria-induced aggregation of the aptasensor which is associated as red-to-purple color change upon high-salt conditions.

[Detection of WU polyomavirus in children with low respiratory tract infections using real-time fluorescent quantitative PCR].

Objective: Development and application of a real time fluorescent quantitative PCR (FQ-PCR) assay for detecting WU polyomavirus in children with low respiratory tract infections.

Methods: The VP2 gene of WU polyomavirus was selected as the detection target, from which the real time primers and probes were designed. The standard curve was established by using recombinant plasmid as template.