Nanostructured quartz crystal microbalances for gas sensing based on metal nanoparticles decorated with peptides. the role of nanomaterial and peptide design for the realization of gas sensor arrays

Aromatic compounds and food patterns have a key role in traceability and quality control of foods. Noninvasive test methods based on the qualitative/quantitative estimation of flavors pattern using sensors are a valuable tool for the food industry. The use of an array of sensors, as in electronic noses (e-noses), has the potential to assay multiple samples quickly and easily. The use of peptides as binding elements in this types of sensors has been demonstrated to be very useful the recognition of different classes of volatile compounds. In order to improve recognition peptides are conjugated to nanoparticles (NPs). In this work we report data obtained using different peptides. designed "in silico" immobilized onto AuNPs or ZnONPs and deposited on quartz crystal microbalances. We found different behavior for the detection of samples with high content of water using AuNPs prepared with different methods and ZnONPs. The sensor arrays based on ZnONPs and AuNPs conjugated with peptides were able to discriminate pure aroma compounds allowing to perform headspace analysis in minutes. Measurement using ZnONPs allowed measurement in water mixtures without drift of the signal and acceptable standard deviations (intraday below 20%). This approach represents a rapid and low-cost method to evaluate volatile patterns in food.