regarding derivitisation

[rrm1987]

actually i was doing derivitisation of T-2 toxin with 1-anthroyl nitrile.In reference they had done using toluene as solvent.I was trying with tetrahydrofuran(THF).but i couldnot able to derivitize the molecule.what could be the reason?

[tom jupille]

Turn the question around: why would you expect it to work? Aside from the fact that the names both start with "T", toluene and THF have few similarities.

[rrm1987]

it's not like that.Usually i take T-2 toxin in buffer which is aqueous where as toluene is non aqueous.but THF is miscible with water.If i use THF then i can skip two steps.Thats why?

[prepcolumn]

actually i was doing derivitisation of T-2 toxin with 1-anthroyl nitrile.In reference they had done using toluene as solvent.I was trying with tetrahydrofuran(THF).but i couldnot able to derivitize the molecule.what could be the reason?

Your derivatization occur through esterification of -OH in T-2 toxin. THF is prone to form hydrogen bonding where as toluene can not. This may be the reason to avoid derivatization..

[rrm1987]

thanks.can you suggest me some other solvent which should be water miscible at the same time it should not form any hydrogen bond with -OH group of T-2

[Don_Hilton]

There may be more involved that must the switch from toluene to THF. The nature of solvent can help to drive a reaction. This can be by solvation of the molecules - and by effects of the solvent on molecular conformation in solution. Concentrations and presence of things like acids or bases can be important as well So...

Looking around for this derivitization reagent one of the first hits I noticed was for the derivitization (applied to hydroxy steroids) was in water and acetonitrile - with triethylamine. http://books.google.com/books?id=osAZ1K ... le&f=false

There are a number of citations in a flier from a vendor of 1-Anthroyl Cyanide http://www.wako-chem.co.jp/english/labc ... ing-OH.pdf. And, it is interesting to note the sensitivity of the reagent to the spatial constraints around the hydroxyl group.

By the way, was the reference you are following http://naldc.nal.usda.gov/download/15139/PDF? This derivitization may have been done on the absense of water to force the esterification. There is competition with the addition of water to the nitrile, to form the acid - and THF will have water in it. YOu may have obtained largely hydrolized derivitization agent.

[rrm1987]

Thanks Mr.Don.it gave a clear insight about whats happening.I would be happy if you give some suggestions/solutions for the following:
1)Is it possible to extract T-2 toxin from water with some organic solvents.
2)I want to derivitise the T-2 in presence of water.

[Don_Hilton]

I'm not sure what they are doing - but it is worth looking at http://en.cnki.com.cn/Article_en/CJFDTO ... 105009.htm to see if acetone/chloroform is a lead for you.

These folks http://link.springer.com/article/10.100 ... 67?LI=true get the toxins into methanol, which is easily evaporated.

Derivitzation of T-2 in water - Given the extra steps in the USDA paper - I suspect that the authors would have tried the more direct path before adding the evaporation steps. I note an e-mail address in the paper. While the paper is 6 years old, it may be worth dropping a line to see if you can get some guidance from an expert.

[rrm1987]

ya.but the problem is we cannot extract the toxin with methanol because methanol is miscible with water.I was doing binding studies with adsorbents in pH 3.2 for T-2 toxin.This extraction holds good if it was done for cereals.

[Don_Hilton]

If the sample has to be in water, I would consider either freeze drying or looking for an SPE cartridge that will allow for elution in an aproic solvent.

[oscarBAL]

Hi rrm; is not cliear for me;do you need to analyzr T2 in water? is that your matirx? if is then the easiest way will be yo use SPE; pass your aqueous sample throught the cartridege (C18 may be) or Inmuno affinity columns; alute your sample with MeOH; dry it and recontitud it with toluenes and follow the dervatization procedure.

Even when you use an Inmunoafinity column and you use MeOH 70% for the extraction; you have to dilute your extract with Water or PBS in order to reduce organic solvent to a minimum before you pass it trhought the column' so is your sample is water you might only adjust the pH and then follow any IA procerdure; but you will always to Dry put your sample before do derivatazation.
Hope this information be use full for you.

PS. Sorry for the bad gammar and spelling I am just coming bad from holidays; Best wiches for every one!!