Zhou Wei, Li Xingyu, Su Wanyun, Zheng Hongbiao, An Guangxin, Li Zhilin, Li Shanshan
School of Mechanical Engineering, Hebei University of Technology, Tianjin 300401, China.
Micromachines (Basel). 2022 Dec 8;13(12):2173. doi: 10.3390/mi13122173.
The somatic cell count (SCC) in raw milk is an important basis for determining whether a cow is suffering from mastitis. To address the problem of an uneven distribution of somatic cells due to cell-adherent sedimentation, among other reasons, during milk sampling, which in turn results in unrepresentative somatic cell counting, a method is proposed for obtaining a uniform distribution of somatic cells and improving the counting accuracy based on a nine-cell grid microfluidic chip. Firstly, a simulation was performed to verify the uniformity of the somatic cell distribution within the chip observation cavities. Secondly, a nine-cell grid microfluidic chip was prepared and a negative-pressure injection system integrating staining and stirring was developed to ensure that the somatic cells were uniformly distributed and free from air contamination during the injection process. As well as the structure of the chip, a microscopic imaging system was developed, and the nine chip observation cavities were photographed. Finally, the somatic cells were counted and the uniformity of the somatic cell distribution was verified using image processing. The experimental results show that the standard deviation coefficient of the SCC in each group of nine images was less than 1.61%. The automatic counting accuracy of the system was between 97.07% and 99.47%. This research method lays the foundation for the detection and prevention of mastitis in cows.
原料乳中的体细胞计数（SCC）是判断奶牛是否患有乳腺炎的重要依据。为了解决牛奶采样过程中由于细胞附着沉降等原因导致体细胞分布不均，进而造成体细胞计数缺乏代表性的问题，提出了一种基于九细胞网格微流控芯片实现体细胞均匀分布并提高计数准确性的方法。首先，进行模拟以验证芯片观察腔内体细胞分布的均匀性。其次，制备了九细胞网格微流控芯片，并开发了一种集成染色和搅拌功能的负压注射系统，以确保在注射过程中体细胞均匀分布且无空气污染。除了芯片结构外，还开发了微观成像系统，并对芯片的九个观察腔进行拍照。最后，对体细胞进行计数，并通过图像处理验证体细胞分布的均匀性。实验结果表明，九组图像中每组SCC的标准差系数均小于1.61%。该系统的自动计数准确率在97.07%至99.47%之间。该研究方法为奶牛乳腺炎的检测与预防奠定了基础。
