基于四氧杂四烯衍生物荧光猝灭的钼酸根传感器

An Optical Chemical Sensor for Molybdate Based on Fluorescence Quenching of TOE

钼酸根离子 Mo O2 - 4在水溶液中对固定于聚氯乙烯 (PVC)膜中的 2 ,2 ,7,7,1 2 ,1 2 ,1 7,1 7-八甲基 -2 1 ,2 2 ,2 3 ,2 4-四氧杂四烯 (TOE)有可逆荧光猝灭作用。据此制成了可测定 Mo O2 - 4浓度的荧光化学传感器 ,其最佳组成为 :5 0 mg PVC、1 0 0 mg癸二酸二异辛脂 (DOS)和 2 .6mg TOE。在 p H=8.0的 Tris/HCl缓冲溶液中Mo O2 - 4的线性响应范围为 1 .43× 1 0 - 7～ 5 .0× 1 0 - 4mol/L,检出限为 4.73× 1 0 - 8mol/L,响应时间小于 3 0 s。该传感器具有良好的重现性、可逆性和选择性 ,其它常见阴离子和阳离子不干扰测定。可测定低含量的白钨矿中的钼。

An optical chemical sensor for molybdate based on reversible fluorescence quenching property of 2,2,7,7,12,12,17,17-octamethyl-21,22,23,24-tetraoxaquaterene(TOE) immobilized in poly(vinyl chloride)(PVC) membrane has been developed. The optimum membrane sensor consists of 2.6 mg TOE, 50 mg PVC and 100 mg diisooctyl sebacate(DOS). The maximum response of the membrane sensor for molybdate was obtained in Tris/HCl buffer solution (pH=8.0). The sensor responds linearly in range of 1.43×10 -7 to 5.0×10 -4 mol/L molybdate, with detection limit of 4.73×10 -8 mol/L, response time less than 30 s. In addition to high reproducibility and reversibility, the sensor also exhibits good selectivity over some common anions and cations. It has been applied in the determination of molybdenum as molybdate in a Scheelite sample, with satisfactory results.