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wjg5118

金虫 (小有名气)

[交流] 【求助】 多糖羧甲基化的一个现象!

我在将多糖进行羧甲基化时出现了一个现象,没法解释了,求教各位大虾!~试验方法如下:

0.5克多糖加入异丙醇15mL, 室温搅拌30min,加入30%NaOH 10mL, 剧烈搅拌90min, 加入氯乙酸3克,50°C反应2h, 此时,停止搅拌,溶液分层,上层为澄清,下层为淡黄色液体,加入盐酸(少量),溶液变为均一,透析得到羧甲基化多糖0.6克

问题是,饭后为什么会分层啊,上下两层各是什么东西啊?

急问!!!

有知道的将送金币,多谢啊!

[ Last edited by ququxiao on 2008-9-20 at 19:03 ]
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modere

金虫 (正式写手)

www.polyindustry.com

★
ququxiao(金币+0,VIP+0):还是鼓励下,多来高分子版:)
ququxiao(金币+1,VIP+0):补上奖励的币币 :)
Synthesis of CM2SPG
The synthesis of CM2SPG with the 4 factors and 3 levels
orthogonal design L9 ( 34 ) was performed by a partially
variant of the method from reference[9 ] . Lyophilized SPG
(10 mg) was immersed by 1 mL isopropanol and the mix2
ture was kept at 40 ℃on a rotary shaker incubator at 120
rpm for 1 h ,then certain volume (67 ,100 or 134μL) of
30 % aqueous NaOH was added and kept at 40 ℃for 1
h. Certain volume ( 26 , 39 or 52 μL ) of 4 mol/ L
chloroacetic acid (CAA) was added to the mixture in a 50
~70 ℃oven for 2~4 h ,then 20 mL distilled water was
added and the mixture was neutralized to pH 6. 5~7 with
0. 1 mol/ L acetic acid.
“”“the mixture was neutralized to pH 6. 5~7 with
0. 1 mol/ L acetic acid.”“”“ 最后这句话
这一段源:自天然产物研究与开发Nat Prod Res Dev 2006 ,18 :5552557
你只是让它羧甲基化,没必要研究两部分是什么吧
4楼2008-09-20 13:09:47
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modere

金虫 (正式写手)

www.polyindustry.com

我考,你至于吗,50个金币。
好像我就是为了挣你金币似的
5楼2008-09-20 14:35:35
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wuwt

木虫 (正式写手)

顺道学习!

谢谢提供!
6楼2008-09-20 17:01:31
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