Determination of trace amounts of phosphate in water after preconcentration using a thermally reversible polymer.
Determination of trace amounts of phosphate in water after preconcentration using a thermally reversible polymer.
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使用热可逆聚合物预浓缩后测定水中的痕量磷酸盐。
DOI：
10.1039/an9931800553
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Y. Mori
中科院分区：
文献类型：
--
作者：
C. Matsubara;S. Izumi;K. Takamura;H. Yoshioka;Y. Mori
聚n -异丙基丙烯酰胺（PNIPAAm）富集测定天然水体中磷酸盐的方法描述了一种热可逆聚合物。聚（n -异丙基丙烯酰胺）在31摄氏度以下的水中可溶，但在31摄氏度以上加热时突然收缩，变得不溶。将钼酸铵和孔雀石绿在45℃下与PNIPAAm水溶液相分离，将钼酸铵和孔雀石绿混合得到的钼- mg试剂反应生成的钼- mg聚合体（P-Mo-MG）掺入PNIPAAm中，并将生成的固体粘附在反应容器壁上。将P-Mo-MG聚集体与PNIPAAm一起溶解在小体积的甲基纤维素溶液中。吸光度（λ max = 627 nm）与磷酸盐浓度成正比，表观摩尔吸光度为2.6 × 10(4) m2 mol-1。该方法使用简易仪器快速测定水中痕量磷酸盐成为可能。磷酸盐的检出限为2 nmol dm-3。该方法成功地应用于自来水、矿泉水、雨水等天然水样中磷酸盐的测定。
A method for concentrating and determining phosphate in natural waters, using poly(N-isopropylacrylamide) (PNIPAAm); a thermally reversible polymer, is described. Poly(N-isopropylacrylamide) is soluble in water below 31 degrees C but shrinks abruptly on heating above 31 degrees C, becoming insoluble. With phase separation of PNIPAAm from aqueous solution at 45 degrees C, a molybdophosphate-Malachite Green aggregate (P-Mo-MG), formed by reaction of a Mo-MG reagent, obtained by mixing ammonium molybdate and Malachite Green, was incorporated in PNIPAAm and the resulting solid stuck to the walls of the reaction vessel. After discarding the supernatant solution by decantation, the P-Mo-MG aggregate was dissolved in a small volume of methylcellosolve together with PNIPAAm. The absorbance (lambda max = 627 nm) was proportional to the concentration of phosphate with an apparent molar absorptivity of 2.6 x 10(4) m2 mol-1. This method makes possible the rapid determination of trace amounts of phosphate in water using simple apparatus. The detection limit was 2 nmol dm-3 of phosphate. The method was successfully applied to the determination of phosphate in natural water samples such as tap water, mineral water and rain water.