Label-free aptamer-based sensor for specific detection of malathion residues by surface-enhanced Raman scattering

Silver‐based surface enhanced Raman spectroscopy devices for detection of organophosphorus pesticides traces

“…Corresponding procedure for modification of AgNPs was reported by Nie et al: a capping layer of spermine offers a positive charge for nanoparticles that attract (nonspecifically) negatively charged aptamers‐malation. The resulting structure presents high selectivity for detection of malation in mixed solution of pesticides . The coating of cluster of Raman reporter molecules by silica favors the development or more stable SERS systems …”

“…41 The mutual incorporation of Raman reporters and antibodies on gold nanoparticlesdeposited on substrates of immunochromatographic assay strips results in a SERS immunoprobe for detection of pyrethroid. 42 Corresponding procedure for modification of AgNPs was reported by Nie et al 43 : a capping layer of spermine offers a positive charge for nanoparticles that attract (nonspecifically) negatively charged aptamers-malation. The resulting structure presents high selectivity for detection of malation in mixed solution of pesticides.…”

“…The resulting structure presents high selectivity for detection of malation in mixed solution of pesticides. 43 The coating of cluster of Raman reporter molecules by silica favors the development or more stable SERS systems. 44 In addition to the modification of plasmonic centers, other important parameter to be considered in production of device refers to the substrate nature.…”

Affinity Sensing Strategies for the Detection of Pesticides in Food

“…SERS has been exploited by several authors for the label-free detection of pesticides using aptamers as recognition elements. Nie et al [ 111 ] and Barahona et al [ 110 ] reported two aptasensors for the detection of malathion in tap water. Barahona et al [ 110 ] developed a composite material based on polymer-AuNP-aptamer sensing particles capable of acting as capture and signal-enhancer for SERS detection of malathion.…”

“…The sensor had a limit of detection of 9.99 × 10 −6 M. In order to test the method, tap water samples were spiked and analyzed. Nie et al [ 111 ] proposed silver nanoparticles modified with positively charged spermine as enhancing and capture reagents for the negatively charged aptamer. The negative phosphate backbone of the aptamer can be combined with the positive spermine by electrostatic interaction.…”