A sensitive and accurate method was developed for the determination of streptomycin using HPLC followed by postcolumn derivatization and fluorometric detection. The analyte was extracted, using aqueous solution from cucumber and Chinese cabbage, by a two-step SPE procedure. The extraction,
cleanup, and chromatography conditions were optimized, and the performance of the analysis method was evaluated. The conditions of chromatography were as follows: the separation was performed on a C18 column; the isocratic mobile phase consisted of acetonitrile and a mixed solution containing
10 mM sodium 1,2-naphthoquinone-4-sulfonate and 0.4 mM sodium 1-heptanesulfonate (25 + 75, v/v); and the flow rate was 1 mL/min. The fluorescence detector was set at an excitation wavelength of 263 nm and an emission wavelength of 435 nm. The calibration curve was linear over the range of
50–2000 ng/mL, with a correlation coefficient of 0.9995. The LOD and LOQ were 10 and 30 ng/g, respectively, in both cucumber and Chinese cabbage. The method was validated for selectivity, linearity, precision, and accuracy. The intraday and interday precision and accuracy were within
10%. The mean recoveries from spiked samples were more than 75%, with RSD lower than 10%.
The Journal of AOAC INTERNATIONAL publishes refereed papers and reviews in the fields of chemical, biological and toxicological analytical chemistry for the purpose of showcasing the most precise, accurate and sensitive methods for analysis of foods, food additives, supplements and contaminants, cosmetics, drugs, toxins, hazardous substances, pesticides, feeds, fertilizers and the environment available at that point in time. The scope of the Journal includes unpublished original research describing new analytical methods, techniques and applications; improved approaches to sampling, both in the field and the laboratory; better methods of preparing samples for analysis; collaborative studies substantiating the performance of a given method; statistical techniques for evaluating data. The Journal will also publish other articles of general interest to its audience, e.g., technical communications; cautionary notes; comments on techniques, apparatus, and reagents.