rat urine for metabolite analysis - (Nov/22/2008 )
Anybody here knows the basic rule of urine analysis for metabolite detection? How to extract the compound that we want from the urine? Why for some method that I read, the urine need to be pre treated with glucoronidase/sulphatase to liberate the metabolite (Phase 1 metabolite)? Glucoronide and sulphate are metabolite themself.... so for what reason they pretreat with glucoronidase/sulphatase?
Kent19, What metabolites are you interested in?
Some analytes require a 24 hour collection (to get sufficient of small quantity metabolites). Others require collection in to an acid washed container.
Some analytes can be measured on a random plain sample (electrolytes, protein etc). Though this may well require a dilution to get onto the linear portion of calibration curves. Other analytes require extraction steps. e.g. catecholamines need a diethyl ether extraction to be measured by HPLC.
What are you interested in and what method will you use to analyse it?
Water insoluble metabolites are glucuronated to make them water soluble (e.g. many drugs and bilirubin). I think you'll be adding the glucuronidase to affect solubility in order to extract. This might be to act on the actual metabolite of interest of to pull off other compunds that would otherwise interfere with your analyte.