Abstract: The residual melamine in milk is one of the important risk factors for human health. A method for the rapid quantitative detection of melamine (MEL) in milk has been designed based on surface plasmon resonance (SPR) technique. As a vector, nano-gold was used to connect MEL to the surface of SPR biosensor chip. The antibody quantity and regeneration conditions were optimized. The designed chip was tested regarding its stability and the accuracy of the proposed method was checked. Using pollution-free milk added with serial concentrations of MEL, the competitive inhibition curve was developed and used to detect real samples. The results showed that the chip exhibited a good reproducibility, with a relative standard deviation (RSD) of 5.05% for 60 replicate determinations. The detection limit of this method was 3.24 ng/mL, much lower than the maximum residue limits adopted by the Codex Alimentarius Commission and by relevant state authorities. The whole analytical procedure including sample preparation could be completed within 30 min and is suitable for rapid in-situ quantitative detection of milk.

Key words: surface plasmon resonance; melamine; milk; quantitative detection

摘要： 牛乳中残留的三聚氰胺对人类健康具有重要危害.利用表面等离子体共振(surface plasmon resonance,SPR)技术,建立一种快速定量检测牛乳中三聚氰胺的方法.以纳米金为媒介将三聚氰胺(melamine,MEL)连接到SPR传感芯片表面,优化最佳抗体用量和再生条件,测试芯片稳定性和方法的准确性.在无污染的牛乳中添加系列质量浓度的MEL,采用竞争抑制法建立抑制标准曲线,并对实际样品进行检测.结果表明:芯片重现性好,重复检测60次相对标准偏差为5.05％,方法检测限为3.24 ng/mL,远低于国际食品法典委员会和国家有关部门规定的残留量.该方法在30 min内完成样品的前处理和检测,适合牛乳生产现场快速定量检测.

关键词: 表面等离子体共振；三聚氰胺；牛乳；定量检测