Development of nanocellulose-based SERS substrate for detection of food contaminants

Abstract

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] The increasing occurrence of food safety incidents in recent years has triggered public health concerns. Thus, food scientists are endeavoring to develop novel methods for accurate, rapid and sensitive detection of food contaminants. The emerging nanoscience and nanotechnology have great potential in developing novel techniques to improve food safety. Nanocellulose is a new type of nanomaterial with unique properties including large surface area, high stiffness, lightness, optical transparency, high porosity, biocompatibility, and biodegradability. The objectives of this study were to develop nanocellulose-based nanocomposites with facile fabrication protocols. The nanocomposites will be used as surface-enhanced Raman spectroscopy (SERS) substrates for rapid detection of food contaminants. Cellulose nanofiber (CNF) nanocomposites were synthesized by placing gold nanoparticle suspension layer onto dried CNF films and used as SERS substrates to detect melamine in milk. The results show that the SERS method was able to detect and quantify melamine in milk and satisfactory detection limits and recovery were obtained. In addition, the performance of CNF-based nanocomposites was further improved by mixing modified CNF with gold nanoparticles. These results demonstrate that CNF/AuNP nanocomposites can be used for rapid and sensitive detection of chemical contaminants in food products.