Chromatography Forum

Hi!
I want to do a multiresidues pesticides analysis (scan mode) for fruit and vegetables. 450 pesticides investigate but i can't buy all pesticide std....i have money for 25 only).
How can i do a quantitative analysis?

Unless you have a way to obtain a good response factor for each pesticide, you can't.

You can try taking the area for the TIC and estimating that the response factor is about the same for each pesticide - but if you look at the results for the 25 you purchase, you will see variation in them. And by one of the corollaries to Murphy's Law, the pesticides not in the mixture will vary more widely yet.

Look around for pesticide standard mixtures and see if you can get a mixture that contains as many pesticides as possible. After that look up all your friends and see what you can beg from them.