Epicatechin wavelength for HPLC

[kez40]

I am conducting an experiment to extract -Epicatechin from cocoa beans and all the journals list 280nm as the wavelength they used, however this wavelength is not generating results. Someone suggested using 210nm which has produced better peaks but I am confused that other similar methods have used 280nm with success. Any suggestions about what I am missing? (flow rate 1ml/min, mobile phase -methanol/H3PO4/distilled water, reverse phase C18column, 5um. Conc 1mg Epicatechin/10ml ethanoic acid)

[HPLCaddict]

A quick google search turnep up an article ("world cocoa foundation" - I wonder if they need someone for quality control, maybe I should apply ):

http://worldcocoafoundation.org/wp-cont ... 200723.pdf

where they say "The wavelength 220 nm was selected as it was the best compromise for both resolution and sensitivity than the more standard 280 nm".

[kez40]

Thank you so much (just want to get the experiment out of the way so can finish writing dissertation) I will take a look now