Ultraviolet and Infrared Analysis of Rotenone: Effect of Other Rotenoids

Abstract

Abstract Biases evidenced by past collaborative trials of ultraviolet (UV) and infrared (IR) methods for rotenone can be caused by interference from other rotenoids that occur in extracts of cubé and derris. In the UV analysis, sumatrol, rotenolone, and deguelin cause positive errors of decreasing magnitude; elliptone, toxicarol, tephrosin, dehydrodeguelin, and dehydrorotenone produce negative biases of increasing magnitude. In the IR analysis, error depends on rotenoid concentration relative to rotenone concentration. At equal proportions, bias is positive with toxicarol and deguelin and negative with other rotenoids. The baseline version of the IR method has an inherent positive bias of approximately 8% but is superior to the base point version because of greater insensitivity to deguelin. The official first action UV method for the determination of rotenone in derris and cubé powder, 6.162–6.163, has been deleted, and the IR method, 6.164–6.165, has been revised to exclude derris products.