September 21, 2021, 01:21:36 PM
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Could you provide a little more about your exptl procedure?

It seems you are binding liposomes to the surface first (in a monolayer?), then looking to see whether your protein binds to this monolayer. Your positive control looks right. Is it possible your test protein is disrupting the lipid monolayer - i.e., your monolayer is dissociating from the surface, leading to an initial loss in RU?
Undergraduate General Chemistry Forum / Dimensional Analysis problem
« Last post by lad03 on Today at 11:06:09 AM »
I got this problem wrong on my quiz:
A 208.9 lb object displaces 2.73 gallons of water when submerged.  What is the density of the object in g/L? (1 gal = 3.79 L, 1 kg = 2.20 lbs) Input your answer in scientific notation (use "E" for x10^, example: 1.0E2, you do not need units)

Selected Answer:   
Incorrect 9.22E2
Correct Answer:   
Correct 9.18E3 ± 5

What did I do wrong and what is the deal with the plus or minus 5 at the end of the correct answer?
High School Chemistry Forum / Re: Possible and impossible compounds
« Last post by Babcock_Hall on Today at 09:41:47 AM »
With respect to the compound on the far right, I would think about the octet rule.
The photon frequency is not 4.97 x 10-19 J. That is the photon energy, as you calculated. What are you doing subtracting a quantity in s-1 from a quantity in J? Have you no sense of units?
You're right. I wasn't paying attention to that. Thank you so much! Despite you being rude (jk) :P
Organic Chemistry Forum / How to functionalize polyallylamine?
« Last post by oldmchorny on Today at 09:00:38 AM »
Dear everyone,

I've got a question regarding the functionalization of polyallylamine. I am not much of a polymer chemist, so please treat me with leniency.
As part of my PhD project I would like to functionalize the amines of polyallylamine (or any similar polymer that consists of a aliphatic backbone and has amines in the side-chains). Specifically I would like to react the amine with an Acylchloride, actually with a Fmoc-chloride derivative I synthesized. The reaction I try to achieve can be depicted as something like:

What would be a proper synthetic strategy to go about it? I know I can usually react amines with Fmoc-chloride in DCM in the presence of DIPEA as a base. But I can not really apply this procedure here, since the polymer behaves weirdly in DCM, as soon as it touches DCM it becomes a gum-like, insoluble, unusable blop. 
I've got two formulations of the polyallylamine: on the one hand the hydrochloride (which of course is not nucleophilic) as a solid and on the other hand I have a watery solution (which is messing with Acylchlorides)

I just naively tried to react the watery polymer solution with sulfonated Fmoc-Cl in water/dioxane with Na2Co3 as a base, but under these conditions the Fmoc-Cl would already start cleaving and causing troubles, also I had no proof the desired reaction actually took place.

Does anyone of you know a good strategy on how to functionalize polyallyamine side-chain amines? I would not need to react every single active site on the polymer, I think it would be sufficient if only like 20-40mol% of the amines would be reacted. But how to achieve that? How to access the active sites of these kind of polymers? I am grateful for any suggestion on how to go about it, as well as for any literature on the topic (I could not find lots of useful literature).


Right now that's a huge goal for me tbh
I have no idea which one to calculate to get the perfect ratio

Ratio of what?

Percent composition is a property of a compound (or mixture), not of a reaction.

Sorry if I didn't mention, and thanks so much for all your help so far I really appreciate it, and regarding your question, it's actually a mixture, I want to figure out how to calculate perfect ratios for a reaction to happen (so that there would be just the right amount of molecules of each reactant, not too much and not too little, for the reaction to happen without any of the reaction's products being greater than the other), I think those are called stoichiometric ratios, right now I wanna learn how to calculate kno3+sugar perfect ratio, but I can't find out how:/
You can use low-boiling solvents like pentane and ether for chromatography, this way you can have aspirator vacuum and ice-cold waterbath when evaporating.
Yes this is the picture.
White - Hydrogen
Red - Oxygen
Black - Carbon
Blue - Nitrogen
Green - Fluorine
Organic Chemistry Forum / Re: Advice on purification of volatile compounds
« Last post by gespy on Today at 03:38:34 AM »
There is really no way but distillation. There is micro-equipment but you will get loss of yield in this small scale.

Yeah, this is my thought at the moment too, just posted here in case I was missing smth I'm not familiar with :)

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