Modified paper‐based substrates fabricated via electrostatic attraction of gold nanospheres for non‐destructive detection of pesticides based on surface‐enhanced Raman spectroscopy

Abstract

BACKGROUNDFlexible surface‐enhanced Raman spectroscopy (SERS) substrates such as paper‐based substrates show great potential for rapid detection of residual chemicals on food surfaces. However, controlling the density and distribution of metallic nanoparticles adsorbed on the paper is still challenging.RESULTSThe amount of gold (Au) nanospheres (51 ± 4 nm) attached on the filter paper modified with 3‐aminopropyltriethoxysilane (APTES) was tunable, increasing as the level of APTES (2.5–15.0 g kg−1) applied for paper modification increased. Moreover, the Au nanospheres were relative evenly distributed on the filter paper modified with 2.5–10.0 g kg−1of APTES, which resulted in excellent intra‐ and inter‐reproducibility of SERS signals for pesticides including thiram, diquat dibromide, and paraquat dichloride (relative standard deviation = 2.2–10.1%). The modified paper‐based substrate could be used to detect as low as 0.05–0.2 mg L−1 of pesticides in standard solutions, and as low as 5–20 ng cm−2 of residual pesticides on apple skins with minimum sample pretreatment.CONCLUSIONThis paper‐based substrate with tunable feature for the density and distribution of nanoparticles is applicable for rapid SERS detection of residual pesticides in fruits and vegetables. © 2023 Society of Chemical Industry.

Application of Surface-Enhanced Raman Spectroscopy Combined with Immunoassay for the Detection of Adrenoceptor Agonists

“…In contrast, SERS is able to produce stronger signals due to the presence of Raman reporter molecules and substrates. Further, the detection sensitivity and spatial discrimination have continuously been improved and extended, which further sets SERS apart from conventional Raman spectroscopy [ 9 , 10 , 11 ]. The literature generally reports two mechanisms to describe the effect of SERS: electromagnetic enhancement (EM) and chemical enhancement (CM) or electron transfer ( Figure 2 ) [ 12 , 13 ].…”