Rod-SERS-nanotags For Highly Sensitive Detection Of Bacteria On The Surface Of Plasmonic Supercrystal

Food-borne bacteria such as E.Coli,Salmonella,etc.,due to its low infection dose and high health risks,can lead to emergence of many food-borne diseases,e.g.,food poisoning,intestinal infectious diseases,etc.,which attract more and more attentions.Traditional methods of detecting bacteria are time-consuming and low-sensitivity.Therefore,developing rapid,sensitive,reliable,and multiplex approach for detecting a variety of pathogens are urgently needed.In the thesis,we prepared an array of tridimensional aligning nanorods as a vertical supercrystal on a chip,and utilized the large-scaled supercrystal as a SERS active substrate.Moreover,we designed a hybridized plasmonic vertical supercrystal combined with rod SERS-nanotags via bacterial interface.Replacement of inherent weak Raman signal of bacteria via rod SERS-nanotags,can lead to highly sensitive SERS detection of Staphylococcus aureus bacteria.In the thesis,we developed an approach for preparing stable rod-sphere superstructured SERS-nanotags.Based on the large-scaled vertical supercrystal,we designed a bacterial aptamer sensor of plasmonic supercrystal/rod-sphere superstructured SERS-nanotags.By aid of multifold optical hotspots,we achieved ultrasensitive highly-selective multiplex detection of Staphylococcus aureus and Salmonella enterica bacteria.