State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, China.
School of Chemistry and Biological Science, Nanjing University Jingling College, Nanjing, 210089, China.
BMC Biotechnol. 2017 Sep 12;17(1):72. doi: 10.1186/s12896-017-0387-9.
α-Lactalbumin (a-LA), β-lactoglobulin (β-LG) and lactoferrin (LF) are of high nutritional value which have made ingredients of choice in the formulation of modern foods and beverages. There remains an urgent need to develop novel biosensing methods for quantification featuring reduced cost, improved sensitivity, selectivity and more rapid response, especially for simultaneous detection of multiple whey proteins.
A novel visualized microarray method was developed for the determination of a-LA, β-LG and LF in milk samples without the need for complex or time-consuming pre-treatment steps. The measurement principle was based on the competitive immunological reaction and silver enhancement technique. In this case, a visible array dots as the detectable signals were further amplified and developed by the silver enhancement reagents. The microarray could be assayed by the microarray scanner. The detection limits (S/N = 3) were estimated to be 40 ng/mL (α-LA), 50 ng/mL (β-LG), 30 ng/mL (LF) (n = 6).
The method could be used to simultaneously analyze the whey protein contents of various raw milk samples and ultra-high temperature treated (UHT) milk samples including skimmed milk and high calcium milk. The analytical results were in good agreement with that of the high performance liquid chromatography. The presented visualized microarray has showed its advantages such as high-throughput, specificity, sensitivity and cost-effective for analysis of various milk samples.
α-乳白蛋白（α-LA）、β-乳球蛋白（β-LG）和乳铁蛋白（LF）具有很高的营养价值，已成为现代食品和饮料配方的首选成分。因此，开发具有成本低、灵敏度高、选择性好、响应速度快等特点的新型生物传感定量方法尤为迫切，尤其是用于同时检测多种乳清蛋白。
本研究开发了一种新颖的可视化微阵列方法，用于测定牛奶样品中的α-LA、β-LG 和 LF，无需复杂或耗时的预处理步骤。该测量原理基于竞争性免疫反应和银增强技术。在这种情况下，作为可检测信号的可见阵列点通过银增强试剂进一步放大和显色。微阵列可通过微阵列扫描仪进行检测。检测限（S/N=3）估计分别为 40ng/mL（α-LA）、50ng/mL（β-LG）、30ng/mL（LF）（n=6）。
该方法可用于同时分析各种原料奶和超高温处理（UHT）奶样品（包括脱脂奶和高钙奶）的乳清蛋白含量。分析结果与高效液相色谱法吻合较好。所提出的可视化微阵列具有高通量、特异性、灵敏度和成本效益等优点，可用于分析各种牛奶样品。
