This paper shows how fish samples could be directly injected into a chromatograph, without any previous extraction, using micellar liquid chromatography, taking as an example the determination of two biogenic amines: putrescine and tyramine, derivatized with 3,5-dinitrobenzoyl chloride. First, the method has been optimized, using an interpretive model, and the best conditions for analysis were: mobile phase containing 0.15 M SDS-6% (v/v) butanol-pH 7, C18 column (125 0.46 mm, 5 μm particle size), UV detection of derivatives set at 260 nm. Second, the method has been validated using spiked samples following the guidelines proposed by the US Food and Drug Administration: linear in the range from 0.5 to 1000 ppm (r 2 >0.999), detection limits of 30 and 40 ppb for putrescine and tyramine, respectively, a 500 ppb limit of quantification in both cases, intra-and inter-day precision (RSD) below 2%, and accuracy between 99.5% and 102.7%. The method is adequate for routine analysis in the determination of these compounds in fish sauces.

A practical liquid chromatographic method has been developed for the selective determination of the levels of spermine in anchovy sauce after derivatization with 3,5 dinitrobenzoyl chloride. The micellar liquid chromatographic separation proposed here uses a C18 column (125×4.6 mm), followed by detection of spermine derivative at 260 nm. Elution of the analyte was performed using a mobile phase of 0.15 M SDS-4% (v/v) 1-pentanol-pH 7 running under isocratic mode at 25°C. Validation parameters were linearity (2–100 μg/mL,R2>0.999), detection and quantification limits (0.4 and 1.2 μg/mL, resp.), precision (less than 3.6%), accuracy (93.3–101.1%), and robustness (less than 4.8%). These results are in agreement with the requirements of the FDA guidelines. The proposed method was successfully applied to the monitorization of spermine formation in unsalted and salted fish sauce samples. The suggested methodology was found useful in routine analysis of spermine in fish sauce samples.

A simple and reliable HPLC method was developed to determine imidacloprid, a chloronicotinyl insecticide that has a highly specific affinity to the nicotinic acetylcholine receptor of insects, above its permissible limit of consumption in fruit juices (orange, apple, and a mixture of pineapple and pear). Samples were injected directly into a Kromasil C18 column, without any pretreatment step, using the micellar mobile phase 0.10 M sodium dodecyl sulfate and 2.5 (v/v) propanol buffered at pH 7 and UV detection at 210 nm. Under these conditions, imidacloprid was eluted in <4 min with no interference by the endogenous compounds of the juice fruits. The analytical parameters linearity (r > 0.9998) and intraday and interday precision (RSD 0.1 2.8 and 0.077, respectively) were obtained in the method validation. LOD and LOQ were calculated to be 0.4 and 1.5 ng/mL, respectively. Recoveries were in the 98103 range. The simplicity of the method makes it a good candidate for application in routine analysis in the area of food control and quality evaluation.

A liquid chromatographic procedure has been developed for the determination of carbaryl, a phenyl-N-methylcarbamate, and its main metabolite 1-naphthol, using a C18 column (250 mm  ×  4.6 mm) with a micellar mobile phase and fluorescence detection at maximum excitation/emission wavelengths of 225/333 nm, respectively. In the optimization step, surfactants sodium dodecyl sulphate (SDS), Brij-35 and N-cetylpyridinium chloride monohydrate, and organic solvents propanol, butanol, and pentanol were considered. The selected mobile phase was 0.15 M SDS-6% (v/v)-pentanol-0.01 M NaH2PO4 buffered at pH 3. Validation studies, according to the ICH Tripartite Guideline, included linearity (r > 0.999), limit of detection (5 and 18 ng mL−1, for carbaryl and 1-naphthol, resp.), and limit of quantification (15 and 50 ng mL−1, for carbaryl and 1-naphthol, resp.), with intra- and interday precisions below 1%, and robustness parameters below 3%. The results show that the procedure was adequate for the routine analysis of these two compounds in water, soil, and vegetables samples.

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