Hi Ines,

Typically people extract so called free amino acids (i.e. those A.A which are NOT part of proteins, peptidoglycan or other macromoleculaes) with water or diluted ethanol (10-20%) solution. The only sever problem is binding by soil solid phase of few basic A.A., such as Lys, Arg and His: they carry positive charge (organic cations) and are strongly bound to soil clays and clay-organic complexes which are predominantly negatively charged. Met is fine, it should not be retained by soil. However I would recommend to spike soil sample once with known amount of Met (say, 1.0 mg/g) to see degree of recovery. Example: unamended soil contains 0.1 mg/g of Met, amended soil contains 1.09 mg/g, then recovery is (1.09-0.1)/1=0.99 (99%).

thank u what abt mobil phase & hplc program RT,decetor plz post details

Kuppusamy, it depends on your system, what particular analytical instruments are available in your lab. There are hundreds of protocols for separation of A.A mixture by HPLC. I am not doing this analysis myself right now, while my former protocols could be obsolete (I used earlier ion-exchange column chromatography). I'm sure that any detectors (IR, UV or conductivity) could work fine with HPLC. You can also derivatize A.A. through silylation to make them volatile and resolve the mixture with GC-MS. It would be probably the most sensitive procedure.

Hi Mulder

Download the article

http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/40822/1/06-2874.pdf

I hope you will find your target

Thank you for your comments.Very helpful so far!

Perhaps www.pickeringlabs.com/landing-pages/amino-acid could be of help depending upon what type of instrumentation you have.

thank u Nicolai S Panikov my HPLC shimadzu SPD 20A ,UV & I am doing pesticides in water analysis just i want know about this still more thats why i asked GC-MS also little i know then , thank u for ur reply

Dear Ines, why you don't use of microorganisms , becasue there are some microorganisms in soil which have ability to produce amino acids