Chromatography Forum

I am analyzing metformin as per Ph.Eur. for that the starting material is dicyandiamide (dcda).so i need to analyze dcda as it is the primary raw material. in that melamine (tricyantriamide) is an impurity. i tried some methods given by the vendors. but it is not giving the satisfactory result. i even tried by spiking melamine with the dcda. but it is not giving the correct result.

Can anyone please help me???

http://www.anchem.ru/forum/read.asp?id=10087 On russian langvigas
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http://www.anchem.ru/forum/read.asp?id=7500 On russian langvigas
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http://www.ncbi.nlm.nih.gov/pubmed/18438016 (China People Republic HPLC DAD+MS in milk)
"Google rules"

Hello Vishnu,

Please send me a request with your email and I will share our method for direct analysis of melamine in milk without any sample prep. It employs Primesep column and guard Our report is in English, and you don't need to translate it from Russian...even with Google

here is a link on method:
http://www.sielc.com/Compound-Melamine- ... amine.html

and on the set up:
http://www.sielc.com/upload/file/pdf/SI ... r_2004.pdf

Contact me if you have questions.

thanks all for the reply,
you can send me the method to my mail id, vshr82@gmail.com or to vishnusank1@gmail.com.
I am not testing for milk products, i am testing for pharmaceuticals and i need to test in 218 nm in a cationic exchange column using 3 pH buffer as mobile phase.

what i need is a clear peak of melamine when i inject dcda with good resolution.

can anybody help???

thanks all for the reply,
you can send me the method to my mail id, vshr82@gmail.com or to vishnusank1@gmail.com.
I am not testing for milk products, i am testing for pharmaceuticals and i need to test in 218 nm in a cationic exchange column using 3 pH buffer as mobile phase.

what i need is a clear peak of melamine when i inject dcda with good resolution.

can anybody help???

Good day, Vishnu

Yes of course, but milk a more complicated object than the pharmaceutical substance.
The Chinese theme search for traces of melamine after the scandal of "baby milk food"
well developed, the work of the classic. From here you can take the chromatographic system.

Generally I do not understand why you are working on such a low wavelength, the melamine maximum of about 280. Check also other impurities?

i fixed that wavelength because our vendor is using the same and he is getting the peaks, but i am not getting in the same method and same conditions that they specified. i dont know the reasons.

is there any specified method for that? it gives me a huge head ache. without finding the method to test this melamine in cyanoguanidine, i cant validate anything. so please help me

We are using a cation column and 240 nm without any problem (see Application Note U-42). Using lower wavelength might give more interferences but should work as well.

Thanks for the reply.

But i am using the ammonium dihydrogen phosphate as mobile phase at 3 pH at 218 nm.

Is there any method related to that for determination of melamine in Dicyandiamide? because i cant change the mobile phase for this determination. or otherwise there may be a problem in quantifying DCDA.

Dear all,
i injected melamine spiked with dcda, it gave a peak. but it is so near to the dcda peak. so i cant quantify that.

Can i improve the resolution by doing something?

I am using whatman 10 scx column using ammonium dihydrogen phosphate in 3 pH as mobile phase.

can anybody help?
THANKS