High pressure liquid chromatographic determination of naphthaleneacetamide residues in apples.

A simple, rapid, and accurate method has been developed for the determination of naphthalene-acetamide (NAAmide) residues in apples. After extraction with chloroform, separation is performed on an RP-8 high pressure liquid chromatographic column using acetonitrile-water (30 + 70) buffered to pH 3.5 at a flow rate of 1.7 mL/min. Either a variable wavelength ultraviolet detector set at 220 nm or a fluorometric detector can be used for quantitation. Average recoveries at the 0.01 and 0.1 ppm spiking levels were 83 and 89%, respectively. Incorporation into a previously described method for naphthaleneacetic acid (NAA) residues in apples has resulted in a procedure for the samultaneous determination of NAA and NAAmide.