ABSTRACT
Hepatitis A virus (HAV) infection has caused substantial morbidity and economic losses to human society, presenting a major public health problem in many parts of the world. Despite the capability for low-concentration detection, current PCR-based techniques are limited by the requirement of specialized lab equipment, trained personnel and a relatively large time-commitment. The need for a prompt in-field quantitative identification of HAV in real samples has led us to develop a chemiluminescent fibre optic genosensor system. In this study, a two-probe sandwich-type hybridization process was implemented on the tip of a fibre optic with an area of 0.12mm2. After optimization of the probes and the working conditions, we showed that the biosensor was able to work for both cDNA and RNA with a relatively large signal/noise ratio and a good sensitivity. An excellent specificity was also confirmed by screening with a broad range of other pathogen samples. The nucleic acid probes method was validated by optimized PCR and qPCR, and may thus be used when field testing would be required.
Subject(s)
Biosensing Techniques/instrumentation , DNA, Viral/analysis , Hepatitis A virus/genetics , Optical Fibers , Calibration , DNA, Viral/chemistry , Equipment Design , Limit of Detection , Luminescent MeasurementsABSTRACT
A clean and highly efficient enantioselective addition of alpha-isocyanoacetamides to aliphatic aldehydes catalyzed by chiral phosphoric acid in the presence of MS 5 A in toluene at -40 degrees C was developed. Excellent yields (85-98%) and good to excellent enantioselectivities (up to >99% ee) were achieved.