Increasing the sensitivity of surface‐enhanced Raman scattering detection for s‐triazine pesticides by taking advantage of interactions with soil humic substances

Abstract

Surface-enhanced Raman scattering (SERS) is a technique which has been well explored for detecting contaminating substances, such as pesticides. Of particular interest has been the use of SERS for quantifying trace levels of the striazine compounds, unraveling the adsorption mechanisms on metallic nanoparticles. Herein, we applied silver nanoparticles (AgNP) as SERS substrates for detecting commercial samples of the pesticides prometryn (PRM) and atrazine (ATZ) and their purified samples in the presence of soil humic substances (SHS). The degrading effect of SHS was assessed through the similarities between the SERS spectra of the purchased pesticides and purified pesticides in the presence of SHS. We also evaluated the mechanisms of interaction between the purified pesticide molecules and SHS. Strong interactions of the amino groups (s-triazine molecules) with the oxygenated groups (SHS) were confirmed via SERS spectra. Such interaction, which is favorable for purified pesticides, allowed to increase the sensitivity of SERS detection, reaching low limits of detection (LOD): 5.5 ppb and 4.0 ppb for unpurified PRM and ATZ (as purchased), respectively, against 1.3 ppb and 21 ppt for purified PRM and ATZ in the presence of the SHS, respectively.

Immunoassay platform with surface-enhanced resonance Raman scattering for detecting trace levels of SARS-CoV-2 spike protein

“…At this linear regime, no intermolecular interactions are predicted to occur and a calibration curve was used to determine the limit of detection (LOD) of the SERRS immunoassay platform [ 76 , 78 ]. LOD was calculated according to the following equation [ 48 , 77 , 79 , 80 ]: where SD Blank is the standard deviation of the “Blank” sample and b is the slope of the calibration curve. The LOD (0.046 ng/mL or 0.60 pM) obtained here is compared in Table 2 with published research results of detection of SARS-CoV-2 spike (S1) glycoprotein.…”

Recent Advances in Nanoparticle-Based Optical Sensors for Detection of Pesticide Residues in Soil

“…They also used AuNPs as the SERS substrate to detect deltamethrin and carbofuran in soil [ 26 ]. With regard to AgNPs, Sanchez-Cortes et al found that prometryn and atrazine in the soil can be detected by using AgNPs as SERS substrates ( Figure 3 a) [ 27 ]. Additionally, this method can be used to analyze DEHA quantitatively [ 28 ].…”

“… Detection of pesticides based on the SERS of nanoparticles ( a ) Soil humic substances-assisted AgNPs SERS substrates for the detection of s-triazine pesticides [ 27 ]. ( b ) Preparation of Ag-nanoplate decorated graphene-sheet SERS substrates for the detection of organic pesticides [ 29 ].…”

“…Both prometryn and atrazine are photosynthesis inhibitors that cause health injuries because they are mutagenic agents as well as endocrine disruptors. Using AgNPs as SERS substrates, Sanchez-Cortes et al [ 27 ] detected prometryn and atrazine. As a result of the strong interaction between the amino groups and oxygenated groups, the sensitivity of SERS was significantly increased, reaching LODs of 1.3 ppb for prometryn and 21 ppt for atrazine.…”

Aprendizado de máquina aplicado em dados de biossensores para diagnóstico de câncer e COVID-19

“…(123)(124)(125) Um dos efeitos utilizados é o efeito Raman com amplificação de superfície (SERS, do inglês Surface-Enhanced Raman Scattering ) (126), usado neste capítulo para diagnóstico de COVID-19. A espectroscopia SERS tem sido utilizada como uma técnica altamente sensível para detectar várias classes de compostos de interesse, incluindo proteínas (biomarcadores de câncer e antígenos virais) (127,128), poluentes emergentes (129), metais pesados (130) e neurotransmissores. (131) O biossensor plasmônico foi constituído de nanopartículas de ouro sobre as quais foram imobilizados anticorpos correspondentes à proteína S do vírus SARS-CoV-2.…”