[AlphaScent]

Hey all,

New super fun time experiment has been given to me.

We want to use Neem Oil as an organic pesticide.  It contains a compound called azadirachtin (see link).

http://en.wikipedia.org/wiki/Azadirachtin

The oil contains many other compounds: Triglycerides, sterols, fatty acids and several terpenes among others.  I have been tasked to come up with a quantitative way to measure to a certain degree how much azadirachtin is in the oil we have acquired. 

GC analysis will not work.  Compound is not volatile.  I was thinking of doing NMR of the substance and having an internal standard of some type.

Has anyone done this type of work before??

Have a good weekend all

[discodermolide]

How accurate do you have to be here? I don't think NMR will be good enough, HPLC will be better.
Some references;
For reviews, see: a) A. J. Mordue, E. D. Morgan, A. J. Nisbet in
Comprehensive Molecular Insect Science : Control, Vol. 6 (Eds. : L. I. Gilbert, K. Iatrou, S. S. Gill), Elsevier, Oxford, 2004 ; b) A. J. Mordue, M. S. J. Simmonds, S. V. Ley, W. M. Blaney, W. Mordue, M. Nasiruddin, A. J. Nisbet, Pestic. Sci. 1998, 54, 277; c) A. J. Mordue, A. Blackwell, J. Insect Physiol. 1993, 39, 903; d) H. Schmutterer, The Neem Tree, Wiley-VCH, Weinheim,
1995.

[AlphaScent]

I do not have to be that accurate, semi-quantitative I guess.  We are looking to most likely enrich the product with azadirachtin through distillation of low boiling constituents most likely.

Thanks for the references, Disco!!

[discodermolide]

I think the concentration of azadirachtin  will be sufficient in what you have. After all the tree produces it in a working concentration.
Removal of the other components that you mentioned may be difficult by distillation unless you have an ultra-high vacuum pump. How much material do you have?

[AlphaScent]

This project is kind of not at the top of my list.  This is just a trial run.  It is three small bottles.  16 fl. oz. each.   I have yet to read your resources, so I want to do that.  Talk about HPLC with my boss.  We do not have ultra-low vacuum.  300 mTorr is about as low as ours go.  That is terrible.  Our pumps blow.

[discodermolide]

300mTorr won't be enough. Perhaps the literature will give you an extraction procedure.
The Neem tree is a fascinating life form. The Indians use it to cure everything.