基于亚甲基蓝的水体急性毒性快速检测方法研究

水体急性毒性的快速检测对保障用水安全至关重要。本研究以荧光假单胞菌为毒性检测的受试体,以细胞膜受损为毒性响应机理,建立了一种新颖的基于亚甲基蓝的水体急性毒性快速检测方法。在本方法中,亚甲基蓝可以对细胞膜受损的细胞进行染色,而不能对细胞膜结构完整的细胞进行染色,因此,当有毒性物质存在并对细胞膜产生破坏时,溶液中的亚甲基蓝会进入细胞对细胞进行染色,从而降低溶液中的亚甲基蓝浓度。通过光谱法检测溶液中亚甲基蓝浓度的变化,就可以实现对水体急性毒性的快速检测。实验结果表明,本方法对3,5-二氯苯酚(DCP)、As3+和Hg2+的最低响应浓度分别为1.6,12.5和3.2 mg/L,对DCP的最低响应浓度比商业化仪器Baroxymeter低。本方法操作简单,检测快速,结果可靠,在水体急性毒性的检测和监测领域具有很好的应用前景。

A New Microbial Biosensor for Detecting and Monitoring Water Acute Toxicity Based on Methylene Blue

A novel method based on methylene blue ( MB) was established for the rapid determination of acute water toxicity with the P. fluorescens as the test organism and the damage of cell membrane as the toxicity response. In this method, the damaged rather than intact cells could be stained positively by MB. Therefore, in the presence of toxicants that could induce the damage of cell membrane, MB would enter into cells, resulting in a decrease in MB concentration of the solution. The acute water toxicity could thus be determined by measuring the changes optically in the concentration of MB in the solutions. The present results displayed that, the detection limits of the reported method for 3,5-dichlorophenol, As3+ and Hg2+ were 1. 6, 12. 5 and 3. 2 mg/L, respectively. In special, the detection limit of the reported method for 3,5-dichlorophenol ( DCP) was lower than that of the commercial equipment, Baroxymeter. The reported method is simple, rapid and reliable, and shows an excellent promise in the determination and monitoring of acute toxicity.