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Seed-growth synthesis is a common strategy to prepare silver nanoplates, whose peculiar plasmonic features can be exploited for surface enhanced Raman scattering (SERS) applications. Here we describe the fabrication and characterization of SERS chips using a peculiar in situ seed growth method, yielding a dense layer of nano-objects directly on a glass slide. In this way, geometric features (i.e. shape and dimensions) of the nano-objects can be tuned by controlling the growth time, obtaining a high concentration of hot spots on the surface. In particular, the SERS response of four kinds of chips were investigated to define the best SERS configuration in terms of size of the silver nano-objects, excitation wavelength and homogeneity of the SERS response. Silver nano-plates with a seeded growth time of 60 min demonstrated remarkable results both in terms of plasmonic enhancement, with an enhancement factor (EF) of 2 × 10 5 using a 532 nm laser excitation, and good homogeneity of the SERS response with intra- and inter-maps RSD of 10% and 5%, respectively. In order to demonstrate application of these chips for real sample analysis, an analytical procedure for the detection of a model pesticide, i.e. thiram fungicide, was developed and applied to its detection on green apples peels. SERS measurements on 60 min seeded growth silver nano-plates chip coupled with a multivariate PLS approach demonstrated high accuracy and repeatability for thiram detection in food matrix within the European law limits., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The existing European Regulation (EC n° 51/2013) prohibits the use of animals meals in feedstuffs in order to prevent Bovine Spongiform Encephalopathy infection and diffusion, however the legislation is rapidly moving towards a partial lifting of the "feed ban" and the competent control organisms are urged to develop suitable analytical methods able to avoid food safety incidents related to animal origin products. The limitations of the official methods (i.e. light microscopy and Polymerase Chain Reaction) suggest exploring new analytic ways to get reliable results in a short time. The combination of spectroscopic techniques with optical microscopy allows the development of an individual particle method able to meet both selectivity and sensitivity requirements (0.1%w/w). A spectroscopic method based on Fourier Transform micro-Raman spectroscopy coupled with Discriminant Analysis is here presented. This approach could be very useful for in-situ applications, such as customs inspections, since it drastically reduces time and costs of analysis., (Copyright © 2017. Published by Elsevier Ltd.)