Azoxystrobin

Azoxystrobin is a synthetic analog of naturally occurring strobilurins and oudemansins. The preventative, curative, eradicant, translaminar and systemic properties facilitate control of a wide range of major plant pathogens in many crops... 

Azoxystrobin degrades rapidly and extensively in/on treated crops and in the environment. The residue definition of azoxystrobin in/on crops is for the parent compound only... 

Water is acidified to pH 1 and passed through a Cig SPE cartridge on which azoxystrobin is retained. The column is dried under vacuum and azoxystrobin residue is eluted from the column. The eluate is adjusted to a known volume and an aliquot is analysed by LC/MS/MS. 

Precondition a Cig (EC) SPE column (l-g/6-mL) with methanol (5mL) followed by another 5 mL of acetonitrile-water (3 7, v/v). Transfer the sample on to the column and allow it to percolate through the column under vacuum, discarding the column eluate. Wash the column with 5 mL of acetonitrile-water (3 7, v/v). Dry the column under high vacuum for 15 min and wash it with hexane (5 mL). Elute the azoxystrobin from the column with 5 mL of ethyl acetate-dichloromethane (11 9, v/v), and evaporate the eluate to dryness under a stream of air in a heating block at 50 °C. Dissolve the sample in 1 mL of acetonitrile-water (1 1, v/v) and filter the solution through a 0.45-p.m syringe filter, transferring the filtrate to an autosampler vial ready for LC/MS/MS analysis. 

Sample extracts should not be stored in aqueous acetonitrile solution for more than 3 days before analysis by LC/MS/MS. Reduced recoveries of azoxystrobin have been observed in samples stored for longer periods of time. 

Azoxystrobin residues in crops, soil and water are stable (>80%) during 2 years of frozen storage. 

DFG method S19 (extended revision) multi-method L 00.00-34 of the Official Collection of Test Methods According to 35 LMBG has been validated for azoxystrobin in orange, garlic, kohlrabi, camomile, fennel seed and tea. Extraction module El, cleanup module GPC and detection module D4 (MSD) were used for orange, kohlrabi and garlic. Extraction module E2, cleanup modules GPC and Cl and detection module D4 (MSD) were used for camomile, fennel seed and tea. 

Garau V, Angioni A, Real AAD, Russo M, Cabras P (2002) Disappearance of azoxystrobin, pyrimethanil, cyprodinil and fludioxinil on tomatoes in a greenhouse. J Agric Food Chem 50 1929-1932... 

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