Research Of Thread-based Microfluidic Nanobiosensor For The Rapid Detection Of Foodborne Bacteria

Food safety is one of the most concerned of the public.Every year,China’s food safety problems cause a large number of economic and social losses.And the pathogenic foodborne microorganisms occupy the main aspect of food safety.In that case,the detection of foodborne microorganisms is particularly important.The current foodborne microorganism detection methods mainly include pathogen culture methods,antigen-antibody reaction-based methods,and PCR methods.These methods often require long detection time and professional operations which are not easy to miniaturize.Aiming at the shortcomings of mainstream foodborne microorganism detection methods,this paper designs a low-cost,convenient and fast thread-based microfluidic nanosensor for the detection of foodborne microorganism.Firstly,a thread-based biosensor for the detection of Vibrio parahemolyticus in seafood was designed.The thread microfluidic channel was made of cotton thread,and a thread-based electrode was prepared by coating the conductive material on the surface of the nylon thread.Mo S₂nanosheets were used to modify the surface of the working electrode,which significantly improves the sensitivity of the sensor.Under the optimized conditions,the average detection time of the sensor was 30 minutes,the minimum detection concentration was 5.74CFU/m L,the detection concentration of Vibrio parahemolyticus was 10-10⁶CFU/m L,and the correlation coefficient was R²=0.9917.In addition,the relative standard deviations（RSD）between the plate counting method and the sensor detection method were compared for the labeled seafood of different concentrations of Vibrio parahaemolyticus which is less than 10%.Secondly,a three-dimensional screen-printed nano-electrochemical biosensor based on BP/Au was innovatively designed in this paper.Pin was used as the separable working electrode.The counter electrode and reference electrode were made on the fabric surface by screen-printing method and PDMS was coated on the back to form a hydrophobic layer.The BP/Au nanomaterials were prepared by liquid phase stripping method,and then modified on the surface of the working electrode to improve the sensitivity of the biosensor.Under the optimized conditions,the average detection time of the sensor is 30 minutes,the minimum detection limit is 0.30ng/m L,and the dynamic monitoring range is 1ng/m L-10μg/m L.