Every year more than 5 million deaths and 300 million illnesses result from pathogenic bacterial infection. Given these aggravations, the development of efficient methodologies to identify and quantify foodborne pathogenic bacteria is an urgent need for the feasibility of more rigorous protocols in food safety. In this regard, up-converting energy nanoparticles (UCNPs) are used as highly sensitive sensors for different public health purposes, including bacterial detection. UCNPs have been proposed as the ideal probe due to their advantages related to the upconversion (UC) phenomenon by materials containing lanthanide ions, exhibiting visible emission under infrared excitation. To increase the efficiency of UC luminescence, silver nanowires (AgNWs) are on the rise in this area. Where, AgNWs conjugated with UCNPs induce the effect of localized surface plasmon resonance (LSPR) which additionally increases the efficiency of NIR light absorption and provides enough energy to increase the luminescence of UC. Furthermore, the incorporation of AgNWs is highly viable and promising, as it can inhibit bacterial growth. This work proposal aims to prepare, for the first time, intelligent food packaging synthesizing UCNPs by the co-precipitation method and later conjugation of antibodies from E. coli and S. aureus bacteria (UCNPS-antibody) for sensing. The polyol method will be used for the AgNWs synthesis by two methodologies to evaluate the relationship between the size of the diameter and the increase in fluorescence intensity per UC for the UCNPs. The packaging will be prepared by physical adsorption method and trapping UCNPs-antibody molecules and AgNWs in bacterial cellulose. Infrared, UV-Vis and fluorescence spectroscopy, nuclear magnetic resonance, hydrogen, carbon, and silicon spectroscopy, including solid-state, x-ray diffraction, scanning, and transmission electron microscopy, thermogravimetric analysis, and bactericidal testing will be carried out. As a result, it is expected to obtain intelligent bacterial cellulose packaging that presents sensing in foodborne pathogenic bacteria using UCNPs and AgNWs. Although UCNPs are a reality in labeling, imaging, and therapy, no work applies this technology in food packaging. This project is innovative, contributes to improving the population's quality of life, reinforces the dialogue between companies and national research groups, and encourages integration between society and universities.
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