Table_1_A highly sensitive lateral flow immunoassay for the rapid and on-site detection of enrofloxacin in milk.DOCX

Enrofloxacin (ENR) is a veterinary antibiotic used to treat bacterial infections in livestock. It chiefly persists in foods and dairy products, which in turn pose severe risks to human health. Hence it is very important to detect the ENR in foods and dairy products to safeguard human health. Herein, we attempted to develop a single-step detection lateral flow immunochromatographic assay (LFIA) using gold nanoparticles (AuNPs) for the rapid and on-site detection of ENR in milk samples. An anti-enrofloxacin monoclonal antibody (ENR-Ab) was conjugated with AuNPs for the specific detection of ENR in milk samples. For sensitivity improvement, many optimization steps were conducted on LFIA test strips. The visual limit of detection (vLOD) was found to be 20 ng/ml with a cut-off value of 50 ng/ml in the milk samples. The obtained LOD and cut-off value were within the safety limit guidelines of the Ministry of food and drug safety, South Korea. The test strip showed negligible cross-reactivity with ENR analogs, and other components of antibiotics, this indicates the high specificity of the LFIA test strip towards ENR. The designed test strip showed good reliability. The visual test results can be seen within 10 min without the need for special equipment. Therefore, the test strip can be employed as a potential detection strategy for the qualitative on-site detection of enrofloxacin in milk samples.

恩诺沙星（Enrofloxacin，ENR）是一种用于治疗家畜细菌感染的兽用抗生素，主要残留于食品及乳制品中，进而对人体健康构成严重威胁。因此，检测食品及乳制品中的恩诺沙星对于保障人体健康至关重要。本研究尝试开发一种基于金纳米颗粒（gold nanoparticles，AuNPs）的单步检测侧向流免疫层析试验（lateral flow immunochromatographic assay，LFIA），用于牛奶样品中恩诺沙星的快速现场检测。将抗恩诺沙星单克隆抗体（anti-enrofloxacin monoclonal antibody，ENR-Ab）与金纳米颗粒偶联，以实现牛奶样品中恩诺沙星的特异性检测。为提升检测灵敏度，研究人员对LFIA测试条开展了多步优化操作。在牛奶样品中，该方法的目视检测限（visual limit of detection，vLOD）为20 ng/ml，临界值为50 ng/ml，所得检测限与临界值均符合韩国食品药品安全部的安全限值指南要求。该测试条与恩诺沙星类似物及其他抗生素成分的交叉反应极弱，表明其对恩诺沙星具有较高的检测特异性。所研制的测试条表现出良好的可靠性，且无需特殊仪器即可在10分钟内获得目视检测结果。因此，该测试条可作为一种潜在的检测手段，用于牛奶样品中恩诺沙星的定性现场检测。