| Autor: |
DR Petersen, RE Link, MW Brooks, S Roy, PC Uden, P Vittum |
| Rok vydání: |
1996 |
| Předmět: |
|
| Zdroj: |
Journal of Testing and Evaluation. 24:149 |
| ISSN: |
0090-3973 |
| DOI: |
10.1520/jte11295j |
| Popis: |
Azadirachtin is a powerful anti-feedant and insect growth-disrupting compound. A primary problem with the utilization of classical extraction techniques for determining azadirachtin is the high hydrophilicity of the compound. Further, since determination by high-performance liquid chromatography (HPLC) requires measuring absorbance at 214 nm, use of methanol for extraction requires a solvent exchange since methanol absorbs in this region. This paper demonstrates the use of supercritical fluid extraction for determination of azadirachtin residues. Methanol-modified supercritical carbon dioxide is used to extract azadirachtin from soil and Japanese beetle adult and larval forms. Greater than 80% of fortified material was recovered at spike concentrations of 1 to 2 µg/g. Using this procedure azadirachtin was determined to be field stable for less than 3 months. Azadirachtin was also successfully extracted from insects showing recovery levels of 75% and greater. The inability of modified supercritical carbon dioxide to cross the insect cuticle was also demonstrated. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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