Development and validation of a rapid and simple HILIC-MS/MS method for the determination of biogenic amines in tuna fish.

The production of biogenic amines (BAs), which are markers of both quality and safety in fish and fishery products, is influenced by the harvesting technique, handling, and other operations including those carried out on board the vessel. Scombroid dark-meat fish (e.g. tuna) are the fish species most frequently linked to histamine poisoning. The most commonly found BAs in fish are histamine, tyramine, putrescine, and cadaverine, which are produced when microbes decarboxylate the corresponding free amino acids. In this study, a rapid and cost-effective HILIC-MS/MS method was developed and validated for the determination of putrescine, cadaverine, histamine and tyramine in tuna samples. A simple sample preparation procedure was followed using the solvent mixture MeOH/H2O (50/50, v/v), 0.1 % acetic acid for protein precipitation and analyte extraction. Intra- and inter-day accuracy, expressed as %Recovery (%R), ranged from 88.0 % (Cad) to 102.7 % (Tyr) and from 85.0 % (Cad) to 99.8 % (Tyr), respectively. Intra- and inter-day precision, expressed as %Relative Standard Deviation (%RSD), ranged from 0.4 % (Tyr, Put) to 3.3 % (His) and from 0.7 % (Tyr) to 5.0 % (Cad), respectively. Limits of detection (LOD) and quantification (LOQ) varied from 0.0009 to 0.0940 mg/kg and from 0.0030 mg/kg to 0.3100 mg/kg, respectively, depending on the analyte. Regarding the potential toxic effects linked to biogenic amines in foods, samples examined in this study showed no risk. The proposed method is an important analytical tool for routine analysis of BAs in fish products.

Headspace gas chromatography-mass spectrometry in the analysis of lavender's essential oil: Optimization by response surface methodology.

A static headspace gas chromatography - mass spectrometry (HS-GC/MS) method was developed and optimized with the aim to be applied in the analysis of lavender essential oil. To obtain a comprehensive profile of the essential oil, the optimum HS-GC/MS method parameters were selected based on a Design of Experiments (DοE) process. Plackett-Burman experimental design was applied by utilizing seven parameters of the HS injection system. Incubation equilibration temperature and time, agitator's vortex speed, post injection dwell time, inlet temperature, split ratio and injection flow rate were screened to select the optimum conditions on the basis of the number and the intensity of the identified compounds. Other parameters, such as sample volume and dilution solvent ratio, were also examined to achieve a comprehensive profile in a chromatographic run of 55 min. With the obtained optimum method, more than 40 volatile compounds were identified in lavender's essential oils from different geographical regions in Greece. The method can be utilized for the quality assessment of lavender's essential oil and provide information on its characteristic aroma and discrimination among species based on the acquired GC-MS profiles.

Liquid chromatography tandem mass spectrometry for the determination of nine insecticides and fungicides in human postmortem blood and urine.

Pesticide poisoning is a common occurrence due to their widespread use, easy access and high toxicity even in small concentrations. The most common poisoning fatalities have been observed due to exposure to organophosphates, carbamates and neonicotinoids, thus development of a method for the rapid determination of these compounds in blood and urine is of great importance for clinical and toxicology laboratories. A simple, fast and reliable method was developed for the determination of 9 pesticides in blood and urine using HPLC-MS/MS instrumentation. In order to find the most suitable sample pretreatment technique, three different sample preparation procedures: SPE, protein precipitation and QuEChERS were compared. The final optimized analytical method was fully validated with the values of parameters such as calibration linearity, accuracy, precision, recovery, matrix effect and stability being acceptable. The method proved reliable, accurate, robust and sensitive and was successfully applied for the quantitation of pesticides in three postmortem cases of pesticides poisoning.