发信人: natto (^O^), 信区: Biology
标 题: Re: 怎么测peptide的concentration?
发信站: BBS 未名空间站 (Tue Sep 26 12:21:35 2006)

In order to measure the concentraion using UV, you need to have either tyr
or trp since the A280 is the absorption due to the two aa. If there is
neither tyr nor trp, go with the direct determination of N in the peptide,
if you DO need precise concentration.

When you weigh out this kind of stuff, make sure there is no statics around.
DO NOT use plastic wares, DO NOT wear gloves. Try spin the sample vial in
order to collect the powder down to the bottom of the vial. Any analytical
balance should work since they will measure to 0.1mg.

Worst to worst, determine the N in the peptide directly，classic,
complicated, but much more accurate. Don't know the English name, though. (
凯氏定氮法)

【 在 honestman (snail) 的大作中提到: 】
: 老板花了1000刀order了一个peptide, 但是却找不到这些peptide有多重, 所以也不知
: 道溶解完了浓度是多少? 因为那些粉末很轻, 无法用称量法. 请问怎么测peptide的浓
: 度呢? 理论上讲一般测蛋白浓度的kit应该不能用吧?
: 另外, 我用water溶解peptide, 不知道为什么很难溶, 而且好像很多杂质. 不知道加热
: 到60度会不会破坏?



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