[mobfesk2]

Hi Chem Forumers!

In an attempt to make 3-sialyllactose, I reacted fetuin (a sialic acid donor) with lactose which hopefully gave me my 3-SL product. I did an NMR on it and found there to be a few impurities of acetic acid (which I can get rid of by freeze-drying).

So, I know I have my product BUT there may also be traces of lactose (the starting material) and free sialic acid. (Fetuin was removed by ultrafiltration). OK, now unfortunately 3 questions arise here  .

How would I know how much lactose and sialic acid I have besides my product?

Can someone also please explain how I can remove these impurities?

Also, how would I calculate the % yield of my product?

Thank you very much for any suggestions! Much appreciated

[neothepoison]

If u want to remove Acetic Acid than neutralize it with proper Base .

Here is the method 2 calculate yield %

Theoritical yield 

You have to first calculate M.W of reagents & yield

than Formula for Theoritical yield is = M.W of Reagent/M.W. of yield

Say it to X gram

Practical Yield

Calculate weight of your yield By balancing Machine

Say it to Y gram




Now % Of Yield

% Of yield =  Y gram / X gram *100

                = -------------- % yield