【 以下文字转载自 Chemistry 讨论区 】 发信人: nantsing (猛龙过江), 信区: Chemistry 标 题: Did anyone conjugate micelles with biomolecules? 发信站: BBS 未名空间站 (Sat May 3 01:44:19 2014, 美东) Micelles were prepared by Phospholipid-PEG-COOH.EDC/NHS was used to activate micelle surface to react with NH2-protein. However, never see the conjugation is successful. Very confused. Any suggestions?
What's your reaction condition? You need to first make the activated NHS ester PEG Phospholipid (or buy it if you can) in organic solvent. After that you can do it in PBS buffer etc. If you run the EDC/NHS activation in water solution, it won't work.
t*3
5 楼
up下
n*g
6 楼
I run the EDC/NHS activation in water solution. Can you explain the reason for not working? Thanks.
in
【在 A******y 的大作中提到】 : What's your reaction condition? You need to first make the activated NHS : ester PEG Phospholipid (or buy it if you can) in organic solvent. After : that you can do it in PBS buffer etc. If you run the EDC/NHS activation in : water solution, it won't work.
A*y
7 楼
Water, H2O, is a nucleophile. It is competing with your NHS during the activation. You will get the acid back. EDC activation need to be without water.
【在 n******g 的大作中提到】 : I run the EDC/NHS activation in water solution. Can you explain the reason : for not working? Thanks. : : in
n*g
8 楼
I did follow Pierce instructions for COOH to amine-protein link in water solution using EDC/NHS activation or just EDC activation. Its protocol did work well for polymer microbead-COOH and amine-protein linking. But it seems not working if I change microbead-COOH to micelle-COOH. I do see people using maleimide-PEG-Phosphilipid to react with thiolated protein.
without
【在 A******y 的大作中提到】 : Water, H2O, is a nucleophile. It is competing with your NHS during the : activation. You will get the acid back. EDC activation need to be without : water.
A*y
9 楼
Are you sure the one you buy is not already activated? EDC activation require anhydrous condition (just go search online). Once Osu-ester is form , it can react with amine in aqueous condition. If you think it is the micelle, then you have to re-think you sequence of reaction.
COOH.
【在 n******g 的大作中提到】 : I did follow Pierce instructions for COOH to amine-protein link in water : solution using EDC/NHS activation or just EDC activation. : Its protocol did work well for polymer microbead-COOH and amine-protein : linking. But it seems not working if I change microbead-COOH to micelle-COOH. : I do see people using maleimide-PEG-Phosphilipid to react with thiolated : protein. : : without
n*g
10 楼
My understanding is that EDC activation can be done in water (pierce website , please search EDC). DSPE does have ammonium ion. Do you think ammonium ion cause the problem?
form
【在 A******y 的大作中提到】 : Are you sure the one you buy is not already activated? EDC activation : require anhydrous condition (just go search online). Once Osu-ester is form : , it can react with amine in aqueous condition. If you think it is the : micelle, then you have to re-think you sequence of reaction. : : COOH.