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4120266 
Journal Article 
High-Performance Liquid Chromatographic Determination Of Cyhexatin In Technical And Wettable Pesticide Powders 
Perez, RL; Barasoain, FF 
1983 
1 
Journal of Chromatography
ISSN: 0021-9673 
NIOSH/00142224 
260 
1 
200-205 
A reversed phase, high performance liquid chromatographic procedure was developed for the routine analysis of the contact acaricide tricyclohexyltin-hydroxide (13121705) (cyhexatin). A wettable powder formulation containing 50 percent cyhexatin was prepared and extracted with methanol/water, in an 80 to 20 ratio, for 30 to 240 minutes. The extracts were separated on an octylsilane reversed phase column using methanol/water/phosphoric-acid, in an 82 to 18 to 1 ratio, as eluent. Chromatographic detection was by ultraviolet radiation at 220 nanometers. Recoveries were determined for each extraction time. Using a 1 hour extraction period, wettable powder formulations containing 12.5 to 75.0 percent added cyhexatin were analyzed, and recoveries were determined. A commercial formulation containing a nominal 50 percent cyhexatin was analyzed 6 times, and the standard deviation was determined. Chromatograms from a cyhexatin working standard solution, a technical solution, and a commercial wettable powder were compared. For various extraction times, recoveries were 79.8 percent after 30 minutes and 98.2 to 99.5 percent from 60 to 240 minutes. Recoveries were 99.2 percent for the 12.5 percent formulation, 98.4 to 98.6 percent for the 25 to 50 percent formulation, and 97.1 percent for the 75 percent formulation. Six duplicate analyses of a nominal 50 percent formulation had findings of 50.2 to 50.6 percent, with a mean of 50.4 percent and a standard deviation of 0.18. Comparison of chromatograms showed that wetting and dispersing agents commonly used in a commercial formulation did not interfere with the cyhexatin peak. With the detector set at maximum sensitivity the minimum detectable concentration of cyhexatin was 0.070 parts per million. The authors suggest that, although this method was developed for analyses of technical and formulated products, it could easily be modified for determinations of cyhexatin residues.