Mastitis, an inflammation of the mammary gland and udder tissue, is the major endemic disease of dairy cattle. In addition to causing health problems to the animals, mastitis leads to the reduction of milk production and quality, representing a significant economic burden for farmers. To enable timely treatment of infected animals with pathogen-specific antibiotics, the development of automated analytical methods for rapid on-site identification and quantification of mastitis-causing pathogens in milk is particularly important.

An immunosensing system for multiplex detection of the two most common mastitis-causing pathogens Staphylococcus aureus and Escherichia coli is proposed in the present study. This immunosensor combines Bead Injection Analysis (BIA), attachment of pathogens onto renewable micro-column, biorecognition of bound pathogens by specific antibodies, conjugated with different fluorescence markers and the measurement of fluorescence signals. The analysis takes 20 min and exhibits detection limits of < 50 CFU mL⁻¹ for E. coli and 100 CFU mL⁻¹ for S. aureus in milk. The applicability of the immunosensor was demonstrated by analyzing milk samples from cows, who were suffering from acute clinical mastitis.

乳腺炎是乳腺和乳房组织的炎症，是奶牛的主要地方病。乳腺炎除了对动物造成健康问题外，还导致牛奶产量和质量下降，这对农民造成了巨大的经济负担。为了能够及时使用病原体特异性抗生素对感染的动物进行治疗，开发自动分析方法以快速现场鉴定和定量牛奶中引起乳腺炎的病原体尤其重要。

在本研究中，提出了一种用于多重检测引起乳腺炎的两种最常见病原体金黄色葡萄球菌和大肠杆菌的免疫传感系统。这种免疫传感器结合了磁珠注射分析（BIA），将病原体附着到可再生微柱上，通过特定抗体对结合的病原体进行生物识别，结合了不同的荧光标记和荧光信号的测量。分析需要20分钟，对大肠杆菌的检出限为<50 CFU mL ^-1，对于金黄色葡萄球菌的检出限为100 CFU mL ^-1在牛奶中。通过分析患有急性临床乳腺炎的母牛的牛奶样品，证明了免疫传感器的适用性。