Determination of Spinosad and Its Metabolites in Citrus Crops and Orange Processed Commodities by HPLC with UV Detection

Abstract

Spinosad is an insect control agent that is derived from a naturally occurring organism and is effective on a wide variety of crops, including citrus crops. A method is described for the determination of spinosad and its metabolites in citrus crops and orange processed commodities. The method determines residues of the active ingredients (spinosyns A and D) and three minor metabolites (spinosyn B, spinosyn K, and N-demethylspinosyn D). For dried orange pulp and orange oil, the method has a limit of quantitation (LOQ) of 0.02 microg/g and a limit of detection (LOD) of 0.006 microg/g. For all other sample matrices (whole fruit, edible fruit, juice, and peel), the method has an LOQ of 0.01 microg/g and an LOD of 0.003 microg/g. The analytes are extracted from the various sample types using appropriate solvents, and the extracts are purified by liquid-liquid partitioning and/or solid-phase extraction. All five analytes are determined simultaneously in the purified extracts by reversed-phase high-performance liquid chromatography with ultraviolet detection at 250 nm.

Determination of spinetoram in leafy vegetable crops using liquid chromatography and confirmation via tandem mass spectrometry

“…The variety of analytical methods thus far employed for the determination of spinosad residues include immunochemical methods (Lee et al ., 1999; Young et al ., 2000), HPLC with ultraviolet detection (West and Turner, 2000; West et al ., 2000), liquid chromatography coupled with mass spectrometry (LC‐MS;Schwedler et al ., 2000; Lehotay et al ., 2005) and LC‐MS/MS (Zywitz et al ., 2004; Sannino 2007; Kamel et al ., 2010). Thus far, there have been no published articles regarding spinetoram in the residue analysis literature.…”

Investigating Role of Abiotic Factors on Spinosad Dissipation

“…Investigations of abiotic (hydrolysis and photolysis) and biotic (aerobic and anaerobic aquatic) processes need to be identified to determine the degradation mechanism of spinosad. Residue analysis of spinosad utilizing high performance liquid chromatography (HPLC) with ultraviolet detector (UV) has been reported in different crops like cotton (West 1996), leafy vegetables, peppers (Yeh et al 1997), citrus (West and Turner 2000), in soil and sediment, as well as in water (West 1997). These studies were performed to meet routine regulatory requirements or to study the fate and degradation in that particular environment.…”

Paraffin Wax Emulsion for Increased Rainfastness of Insecticidal Bait to Control <I>Rhagoletis pomonella</I> (Diptera: Tephritidae)

“…The liquid containing spinosad residue was collected in 1.5-ml glass vials and immediately brought to MSUÕs Analytical Pesticide Laboratory, where the concentration of spinosad in the liquid was determined using standard methods (West and Turner 2000). We calculated the amount of dislodgeable spinosad per droplet because a few droplets in some of the lids became detached and were lost during the last period of exposure to simulated rain.…”