The use of biosensors by using microorganisms such as bacteria have short life cycles and provide other advantages. One colorimetric biosensor technique that has been developed is the use of a biosensor utilizing the incorporation of Prussian blue formation reactions mediated by E. coli bioreactors with ferricyanide. Immobilization is a method that allows the bacteria can be used for long-term without reducing its ability as bioreceptor. This study aimed to develop a novel and rapid immobilized bacterial biosensor for the detection of toxic compound in water and to evaluate their analytical performances. Immobilization of E. coli performed by trapping method using alginate material support. The bacterial suspension was mixed with sodium alginate (1:1 v/v), and the mixture was continuously dropped in CaCl₂ solution to be a form of beads. The beads were used as bioreceptor to detect toxicants regarding cadmium, arsenic, mercury, chromium and lead solutions with Prussian blue as a colorimetric indicator. The linearity and sensitivity of detection of beads to the toxicants were tested, the stability of repeated use and storage were evaluated as well. The results showed that E. coli could be immobilized using alginate with response value was correlated with toxic concentration. The developed biosensor was more stable when used repeatedly and could be stored in a long time. The immobilization of E. coli in calcium alginate bead was successfully performed as a biosensor system for monitoring acute toxicity in water.

通过使用诸如细菌的微生物来使用生物传感器具有短的生命周期并提供其他优点。已开发的一种比色生物传感器技术是利用生物传感器的利用，该生物传感器利用了由大肠杆菌生物反应器介导的普鲁士蓝形成反应与铁氰化物的结合。固定化是允许细菌可以长期使用而不降低其作为生物受体的能力的方法。这项研究旨在开发一种新型的快速固定的细菌生物传感器，用于检测水中的有毒化合物并评估其分析性能。固定化大肠杆菌通过使用藻酸盐材料载体的捕集方法进行。将细菌悬浮液与藻酸钠（1∶1v / v）混合，并将混合物连续滴加在CaCl ₂溶液中，成为珠粒形式。珠子用作生物受体，以普鲁士蓝为比色指示剂检测镉，砷，汞，铬和铅溶液中的有毒物质。测试了珠子对毒物检测的线性和灵敏度，还评估了重复使用和储存的稳定性。结果表明，藻酸盐可固定化大肠杆菌，其响应值与毒物浓度有关。反复使用时，开发的生物传感器更加稳定，可以长期保存。的固定海藻酸钙珠粒中的大肠杆菌已成功用作监测水中急性毒性的生物传感器系统。