The amount of microbeads ingested by Daphnia magna decreases on exposure to toxic materials; tins oenawor was used to develop a toxicity test. To determine the toxicity of seven metals, D. magna were collected and hom...The amount of microbeads ingested by Daphnia magna decreases on exposure to toxic materials; tins oenawor was used to develop a toxicity test. To determine the toxicity of seven metals, D. magna were collected and homogenized, and the fluorescence intensity of the microbeads ingested by D. magna was measured. The amount of ingestion was determined from fluorescence intensity. The fluorescence intensity was half of that of the controls which was measured as the 30 min-FI50, and these data correlated well with those from an acute immobilization method （24 h-EC50）. An advantage of the method using fluorescent beads is that an estimate of the 24 h-EC50 can be obtained.展开更多
Fluorescent microspheres of polystyrene-based Eu（Ⅲ） complexes were prepared from TentaGel resin, 2,6-bisbenzimidazolylpyridine and europium nitrate. The microspheres were characterized by FTIR spectroscopy, element...Fluorescent microspheres of polystyrene-based Eu（Ⅲ） complexes were prepared from TentaGel resin, 2,6-bisbenzimidazolylpyridine and europium nitrate. The microspheres were characterized by FTIR spectroscopy, elemental analysis, XPS measurements and fluorescence spectroscopy. Characteristic red emission under irradiation of 365 nm light from a hand-held UV lamp was observed for the microspheres either in a solution or solid-state. Fluorescent quenching was observed when the microspheres were exposed to a trace amount of diethyl chlorophosphate （DCP） in the dispersion. The material and property can be potentially used to fabricate chemosensor in the detection of organophosphates.展开更多
文摘The amount of microbeads ingested by Daphnia magna decreases on exposure to toxic materials; tins oenawor was used to develop a toxicity test. To determine the toxicity of seven metals, D. magna were collected and homogenized, and the fluorescence intensity of the microbeads ingested by D. magna was measured. The amount of ingestion was determined from fluorescence intensity. The fluorescence intensity was half of that of the controls which was measured as the 30 min-FI50, and these data correlated well with those from an acute immobilization method （24 h-EC50）. An advantage of the method using fluorescent beads is that an estimate of the 24 h-EC50 can be obtained.
基金Project supported by Research Foundation of the General Armament Department (2008 CD 012)
文摘Fluorescent microspheres of polystyrene-based Eu（Ⅲ） complexes were prepared from TentaGel resin, 2,6-bisbenzimidazolylpyridine and europium nitrate. The microspheres were characterized by FTIR spectroscopy, elemental analysis, XPS measurements and fluorescence spectroscopy. Characteristic red emission under irradiation of 365 nm light from a hand-held UV lamp was observed for the microspheres either in a solution or solid-state. Fluorescent quenching was observed when the microspheres were exposed to a trace amount of diethyl chlorophosphate （DCP） in the dispersion. The material and property can be potentially used to fabricate chemosensor in the detection of organophosphates.
