{Reference Type}: Journal Article {Title}: Ultrasensitive and selective detection of sulfamethazine in milk via a Janus-labeled Au nanoparticle-based surface-enhanced Raman scattering-immunochromatographic assay. {Author}: Wang Y;Zou M;Chen Y;Tang F;Dai J;Jin Y;Wang C;Xue F; {Journal}: Talanta {Volume}: 267 {Issue}: 0 {Year}: 2024 Jan 15 {Factor}: 6.556 {DOI}: 10.1016/j.talanta.2023.125208 {Abstract}: Sulfamethazine (SM2) is an antibacterial drug,which has been extensively used in human and veterinary medicine, long-term consumption of which may lead to the accumulation of sulfonamides in the body. Detection of sulfonamides often uses microbiological approaches, mass spectrometry and chromatography, which are expensive and time-consuming. Surface-enhanced Raman scattering-based immunochromatographic assay (SERS-ICA) has been recently applied in the detection. Herein, a Janus-labeled Au nanoparticle with subnanosized SiO2-monoclonal antibody and SERS reporter (DTNB) modified simultaneously (mAbAuNpDTNB) has been developed in a SERS-based lateral flow immunosensor, which can be used for rapid, quantitative and ultrasensitive detection of sulfamethazine residue in milk. The mAbAuNpDTNB exhibits a specific array on a paper stripe, which not only identifies sulfamethazine but also straightforwardly exposes the Raman reporter between the AuNps via self-assembly. The detection sensitivity of SERS-ICA for sulfamethazine reached 0.1 pg/mL, which was far below the previously published value by ELISA and the maximum residue limit set by the European Union. The entire SERS-ICA detection for sulfamethazine was completed within 15 min. Furthermore, high accuracy for this assay was exhibited in the spiking experiment with a recovery percentage of 88.1%-112.7%. The results demonstrated that this SERS-ICA can potentially be applied in point-of-care testing as an ultrasensitive and quantitative to semi-quantitative analytical method.