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吴桂叶

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[交流] 【求助】环糊精与羧基反应

想和大家交流请教一下环糊精和酸反应的条件，
比如环糊精与罗丹明反应。反应条件如下： Lissamine rhodamine B ethylenediamine (2 mg, 3.3 mmol) and highmolecular mass CDP (Mw ) 97 kDa, 37.8 mg) were dried under vacuum for 4 h. Dimethyl sulfoxide (DMSO, 3.7 mL) was added to the mixture, followed by 1-ethyl-3-[3-(dimethylamino) propyl]carbodiimide hydrochloride (EDC, 2.6 mg, 13.6 mmol) and N-hydroxysuccinimide (NHS, 1.6 mg,13.6 mmol). The mixture was stirred for 24 h and dialyzed against water using a [color=]MWCO of 25 000 for 72 h in the dark.The polymer-dye conjugate (HRhod) was obtained in 80% yield (32 mg) after lyophilization. The weight percent of rhodamine on the conjugate was determined by measuring the absorbance from rhodamine at 560 nm.
对其中的MWCO of 25 000 透析不太明白。

环糊精与水杨酸反应：SA (0.1036 g, 0.75 mmol) and CDI (0.179 g) were dissolved in 3 ml of DMSO, and the mixture was stirred at room temperature for 30 min. After adding γ-CyD (0.6485 g,0.5 mmol) and TEA (4 ml), the mixture was stirred at room temperature for 18 h. Approximately, 200 ml of acetone was added to the reaction solution, and the precipitate was collected under reduced pressure. The precipitate was purified by ion-exchange column chromatography (DiaionTM HP-20, Mitsubishi Chemical, Tokyo, Japan) and the resulting conjugate was eluted with methanol/water with increasing methanol content. The eluents were monitored by thin layer chromatography (TLC), and the conjugate appeared in the eluents of 30—50% methanol in water. After methanol was removed under reduced pressure, the solution was lyophilized to yield 0.34 g (24%) of SA/γ-CyD conjugate. Rf value_0.75 (TLC: silica gel 60F254 (Merck, Darmstadt, Germany); ethyl acetate–2-propanol–ammonium hydroxide–water (7 : 7 : 5 : 4, v/v); indicator p-anisaldehyde;
其中处理用离子交换柱不太明白，一定要用离子交换柱吗？

[ Last edited by 吴桂叶 on 2009-8-1 at 10:29 ]

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