A microbial test-system for real-time determination of low/residual concentrations of kanamycin in a liquid without the need for special labels is presented. The main element of the system was a piezoelectric resonator excited by a lateral electric field based on an X-cut lithium niobate plate 0.5 mm thick with two rectangular electrodes on one side. On the other side of the resonator, there was a 1.5 ml liquid container. As a sensory element we used Escherichia coli B-878 microbial cells, which are sensitive to kanamycin. For measurement 1 ml of this cells suspension was placed in a liquid container and then the test liquid in the amount of 2 μl containing kanamycin was added. The change in the real part of the electrical impedance of the resonator before and after the test liquid addition was used as an analytical signal which indicated the presence of kanamycin. The lower limit of determination of kanamycin turned out to be 1.0 μg/ml with an analysis time of 10 min. The test-system allows to detect kanamycin in the presence of such antibiotic as ampicillin and polymixin.

介绍了一种无需特殊标签即可实时测定液体中低/残留卡那霉素浓度的微生物测试系统。该系统的主要元件是由横向电场激发的压电谐振器，该压电谐振器基于 0.5 mm 厚的 X 切割铌酸锂板，一侧有两个矩形电极。在谐振器的另一侧，有一个 1.5 毫升的液体容器。作为感觉元素，我们使用了大肠杆菌B-878微生物细胞，对卡那霉素敏感。为了测量，将1ml这种细胞悬浮液置于液体容器中，然后加入2μl含有卡那霉素的测试液体。在添加测试液体之前和之后谐振器的电阻抗实部的变化用作表明卡那霉素存在的分析信号。卡那霉素的测定下限为 1.0 μg/ml，分析时间为 10 分钟。该测试系统允许在氨苄青霉素和多粘菌素等抗生素存在的情况下检测卡那霉素。