Chromatography Forum

Hi all,

Anyone have any experience with analysing Ethephon, a plant growth regulator? Hope you could share the method and experience with me.

Hello Leon, I was trying to do that along long time ago! in Central America, I never though to find someone with the same problem, I am Sorry to desapoint you , But I could not to analyze it, I suposs you you are talking about recidues, because the product, is a very easy and weird titration.
I think that this post should be in GC forum, because the ehtephon residues is analyzed by GC, ussing a derivatization, Ican not remember at this moment, I found and article fron Italy, (if my memory is correct), but I could not to get the same results, if you get some GC procedure maybe I could help!

good luck!
Oscar.

Hello again
here, some abastrarct that I found:

http://www.ncbi.nlm.nih.gov/entrez/quer ... t=Abstract

http://www.inchem.org/documents/jmpr/jm ... 77pr25.htm

There are other methods beside the derivatization, analysing ethylene
after hydrolisis, but you have to remember that the most of the fruits produce ehtylene, during the maduration process.

For comparing tested samples to the technical standard I use:
TSK G2000 SW XL 5microm; 300x7,8 mm + TSK G3000 SW XL 5microm; 300x7,8 mm (TosoHaas) temp. 40oC. Eluent: 0,25M NaCl i 0,01M NaH2PO4; pH=4,5; flow: 1,0 ml/min.
About 100 mg of sample dissolved in eluent in 10 ml measuring flask and heated 30-60 min at water bath (about 60oC).
Detection RI.

Hi Poskrobko Jan,

Thanks for sharing the method but I am sorry I cannot really understand it. Is this an LC method? Actually I am looking for an LC method for ethephon residue analysis. I was hoping I could skip the derivatisation step necessary for GC method. Do you have the reference for the full paper for this method?

Hi Oscar,

Thanks Oscar for the info. Actually I am trying to analyse for ethephon in beansprouts. Do you think, besides its use for ripening, can it be used for beansprout production to yield shorter roots?

Leon! There was parameters for LC metod I developed and I use with no problems. Unfortunatell it is not in the paper.
Jan

Hi Leon,
I don't have any idea if you can use ethephon for beansprouts, you can look at this paper:L
http://www.agrocourier.com/medien/allge ... UeS_GB.pdf

Oscar.

[quote="Poskrobko Jan"]For comparing tested samples to the technical standard I use:
TSK G2000 SW XL 5microm; 300x7,8 mm + TSK G3000 SW XL 5microm; 300x7,8 mm (TosoHaas) temp. 40oC. Eluent: 0,25M NaCl i 0,01M NaH2PO4; pH=4,5; flow: 1,0 ml/min.
About 100 mg of sample dissolved in eluent in 10 ml measuring flask and heated 30-60 min at water bath (about 60oC).
Detection RI.[/quote]

Poskrobko Jan,

What is RI? What is the sample that u test on using this method? What is the purpose of the heating? Can I have the full detail of the method?

RI is Refractiv Index Detector.
I am working for testing purity of ethephon samples from producers. From Your last posts I see You are talking about determination of traces of ethephon in biological material. If yes, then sorry, there are different problems and I don't think my method is useful!
Jan