Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573, Japan.
Lab Chip. 2012 Apr 7;12(7):1309-15. doi: 10.1039/c2lc20952g. Epub 2012 Feb 17.
Subclinical mastitis is a common infectious disease affecting dairy cows. To develop an early diagnostic device for this disease, we focused on measuring an increase in the number of neutrophils in raw milk of mastitic cows. Superoxide anions (O(2)(-)), secreted by neutrophils, can be a good indicator of neutrophil concentration, and therefore, the seriousness of the mastitis. In this study, neutrophils in raw milk samples were separated from fat globules in a flow channel using differences in specific gravity and specific adhesion of neutrophils to P-selectin. Neutrophils trapped in the flow channel were subsequently concentrated in an array of micropillars of a working electrode modified with P-selectin and superoxide dismutase. The O(2)(-) secreted from the trapped neutrophils was electrochemically detected. A difference in the detection current was observed between normal and mastitic milk samples. A clear linear relationship between the electric current and cell density was observed.
隐性乳房炎是一种常见的奶牛传染病。为了开发这种疾病的早期诊断设备，我们专注于测量乳腺炎奶牛原奶中中性粒细胞数量的增加。中性粒细胞分泌的超氧阴离子（O(2)(-))可以作为中性粒细胞浓度的良好指标，因此也可以作为乳腺炎严重程度的指标。在这项研究中，使用中性粒细胞与 P-选择素的特异性附着和比重差异，在流道中将原奶样本中的中性粒细胞与脂肪球分离。随后，被捕获在流道中的中性粒细胞在经 P-选择素和超氧化物歧化酶修饰的工作电极的微柱阵列中被浓缩。从捕获的中性粒细胞中分泌的 O(2)(-)被电化学检测到。在正常和乳腺炎牛奶样本之间观察到检测电流的差异。观察到电流与细胞密度之间存在明显的线性关系。
