Immunosensor For Rapid Detection Of Enterobacter Sakazakii Based On Mwcnts And Aunp

Enterobacter sakazakii was common conditioned pathogen which usually parasitic in the intestinal of animals and human people, and Enterobacter sakazakii nearly did no harm for adult, but for infants and young children, it’s really a great potential danger, especially for those newborns, because it could cause a rare, but life-threatening disease. Milk powder had been identified in several previous reports to be the main sources of Enterobacter sakazakii, so it’s necessary to develope new technology for rapid detection of Enterobacter sakazakii and confirm our food safety.Immunosensor was an analytical technique which combine the amplification of enzyme reaction, the specificity of immune response and the high sensitivity of electrochemical analysis. This analytical technique had these advantages such as fast, specificity, high sensitivity, low cost, etc. It had good potential applications and was becoming an important technique for detecting antigenic substances. Immunosensor based on new nano-materials such as multi-walled carbon nanotubes, gold nanoparticles and others was becoming a new research hotspot.This paper aimed at study and improve the novel electrochemical immunosensor and applied it to rapid detection of Enterobacter sakazakii, the comment of this paper were described as follow:1Immunosensor for rapid detection of Enterobacter sakazakii based on gold nanoparticles/thionine modified screen printed carbon electrodeIn order to develop a novel immunosensor for rapid detection of Enterobacter sakazakii, gold nanoparticles (AuNP) was attached on screen printed carbon electrode by electrodeposition, then thionine (Thi) and horseradish peroxidase-conjugated antibody E.Sakazakii (HRP-anti-E.Sakazakii) were self-assembled on the AuNP modified screen printed carbon electrode. Cyclic voltammetry and electrochemical impedance spectroscopy were used to characterist the different assemble procedure of electrode, Enterobacter sakazakii was detected by peak current reduction of the cyclic voltammetry before and after the immune rection. Under the optimum conditions, the new enzyme immunosensor had shown a good linear range of103～109cfu/mL with the detection limit of6.9×101cfu/mL (S/N) for detection of Enterobacter sakazakii. The immunosensor had good reproducibility with a relative stander deviation of6.6%and good stability for the CV response of immunosensor was90.3%of the initial state value. This novel immunosensor had many advantages like specially, sensitively and rapid, and it also could be used as model to constructed immunosensor for the rapid detection of other pathogens.2A novel immunosensor for rapid detection of Enterobacter sakazakii based on multi-walled carbon nanotubes/carboxymethyl chitosan-alginate/thionine modified screen printed carbon electrodeThis paper aimed to develop a new immunosensor based on multi-walled carbon nanotubes (MWCNTs) for rapid detection of Enterobacter sakazakii. The mixture solution of sodium alginate (SA) and carboxymethyl chitosan (CMC) was used to entrap MWCNTs. First MWCNTs-SA/CMC was dropped on screen printed carbon electrode, and then thionine (Thi) and horseradish peroxidase-conjugated antibody E.Sakazakii (HRP-anti-E.Sakazakii) were self-assembled on MWCNTs/SA-CMC modified electrode. Cyclic voltammetry and electrochemical impedance spectroscopy were used to investigate the electrochemical characteristics of different electrode, Enterobacter sakazakii was detected by peak current reduction of the cyclic voltammetry before and after the immune reaction. Under the optimum conditions, the novel enzyme immunosensor had shown a good linear range of103～109cfu/mL with the detection limit of6.6×101cfu/mL (S/N) for detection of Enterobacter sakazakii. The immunosensor had good reproducibility with a relative stander deviation of6.3%and good stability for the CV responsence of immunosensor was92.3%of the initial state value. This novel immunosensor based on MWCNTs had many advantages such as specifically, sensitively and rapid which could be used as model to constructed immunosensor for the rapid detection of other foodborne pathogens.3A novel immunosensor for rapid detection of Enterobacter sakazakii based on multi-walled carbon nanotubes/chitosan/thionine/gold nanoparticles modified screen printed carbon electrodeThis paper aimed at to construct a novel immunosensor for rapid detection of Enterobacter sakazakii based on gold nanoparticles and multi-walled carbon nanotubes modified electrode. Chitosan (CS) was used to disperse MWCNTs, AuNP was steadily bonded to the surface of multi-walled carbon nanotubes via amido-Au affinity of Au, Thi, and CS. First, The mixture solution of MWCNTs and CS was dropped on electrode and dry in room temperature; then the modified electrode immersed in thionin solution; third, the gold nanoparticles solution was dropped on the prepared electrode and stand overnight; last, horseradish peroxidase-conjugated antibody (HRP-anti-E. Sakazakii) was dropped on the MWCNTs and AuNP modified electrode. Cyclic voltammetry and electrochemical impedance spectroscopy were used to investigate the electrochemical characteristics of different modified electrode, Enterobacter sakazakii was detected by peak current reduction of the cyclic voltammetry before and after the immune reaction. Under the optimum conditions, the novel enzyme immunosensor had shown a good linear range of102～109cfu/mL with the detection limit of7.6×101cfu/mL (S/N) for detection of Enterobacter sakazakii. The immunosensor had goog reproducibility with a relative stander deviation of7%and good stability for the CV responsence of immunosensor is94.5%of the initial state value. This novel immunosensor based on MWCNTs and AuNP has many advantages like specifically, sensitively and rapid which also couldbe be used as model to constructed immunosensor for the rapid detection of other foodborne pathogens.