Gaur R K, Gupta K C
DNA Synthesis Laboratory, CSIR Centre for Biochemicals, Delhi, India.
Anal Biochem. 1989 Aug 1;180(2):253-8. doi: 10.1016/0003-2697(89)90426-0.
A simple and sensitive method for the estimation of polymer-supported amino groups is reported. The polymer support is treated either with N-succinimidyl-4-O-(4,4'-dimethoxytrityl)-butyrate or 2,4-dinitrophenyl-4-O-(4,4'-dimethoxytrityl)-butyrate and a catalytic amount of 4-dimethylaminopyridine. After removal of the excess reagent through washing, a weighed quantity of the polymer support is treated with perchloric acid to release the 4,4'-dimethoxytrityl cation from the solid support into the solution. The released 4,4'-dimethoxytrityl cation, which has a strong absorption (epsilon 498 = 70,000/M) at 498 nm, is determined spectrophotometrically. A comparative study of these reagents with N-succinimidyl-3-(2-pyridyldithio)-propionate, 4,4'-dimethoxytrityl chloride, and sodium 2,4,6-trinitrobenzenesulfonate methods is also included.
报道了一种用于估算聚合物负载氨基的简单且灵敏的方法。将聚合物载体用N-琥珀酰亚胺基-4-O-(4,4'-二甲氧基三苯甲基)-丁酸酯或2,4-二硝基苯基-4-O-(4,4'-二甲氧基三苯甲基)-丁酸酯以及催化量的4-二甲氨基吡啶处理。通过洗涤除去过量试剂后，将一定重量的聚合物载体用高氯酸处理，以使4,4'-二甲氧基三苯甲基阳离子从固体载体释放到溶液中。释放出的4,4'-二甲氧基三苯甲基阳离子在498nm处有强吸收（ε498 = 70,000/M），通过分光光度法测定。还包括了这些试剂与N-琥珀酰亚胺基-3-(2-吡啶二硫基)-丙酸酯、4,4'-二甲氧基三苯甲基氯和2,4,6-三硝基苯磺酸钠方法的比较研究。
