8 research outputs found
Analysis in Dried Fruit by LC/MS/MS and a Modified QuEChERS Procedure
A sensitive and reliable multi-mycotoxin method
was developed for the simultaneous determination of 16 toxicological
important mycotoxins, such as aflatoxins B1, B2,
G1, and G2; enniatins A, A1, B, and B1; beauvericin; ochratoxin
A; fumonisin B1, B2, andB3; diacetoxyscirprenol; HT-2;
and T-2 toxin in dried fruits using liquid chromatography
combined with electrospray ionization-triple quadrupole
tandem-mass spectrometry. Mycotoxins have been extracted
from the samples using a modified quick, easy, cheap, effective,
rugged, and safe procedure. The method was based on a
single extraction with acidified acetonitrile, followed by
partitioning with salts, avoiding any further clean-up step.
Limits of detections ranged from 0.08 to 15 μg kg−1 and limits
of quantification ranged from 0.2 to 45 μg kg−1, which were
below the legal limit set by the European Union for the
legislated mycotoxines. The recoveries in spiked samples
ranged from 60 to 135 % except for beauvericin using
matrix-matched calibration curves for quantification, with
good inter- and intraday repeatability (respective relative standard
deviation ≤20 and 9 %). The developed method was
applied to 15 commercial dried fruits: raisins, figs, apricots,
plums, and dates purchased in local markets from Spain.
Among the mycotoxins studied, enniantins and aflatoxins
were the most predominant mycotoxins
Simultaneous determination of eight underivatized biogenic amines in fish by solid phase extraction and liquid chromatography-tandem mass spectrometry
Biogenic amines on fish tissue are formed as a result of bacterial contamination and spoilage during storage.
A new method based on liquid chromatography (LC) and tandem mass spectrometry (MS/MS) using
a triple quadrupole (QqQ) analyser was developed for the analysis of eight biogenic amines (cadaverine,
histamine, phenylethylamine, putrescine, spermine, spermidine, tyramine and tryptamine) in fish tissues.
Sample preparation was performed by extraction with trichloroacetic acid 5% and solid phase
extraction clean up with STRATA X cartridge. The MS/MS method was validated and compared with a
method based on the analysis of dansyl derivatives by LC and fluorescence detector (FD). MS/MS achieved
higher sensitivity (from 0.02 mg kg1 for spermidine and phenylethylamine to 0.2 mg kg1 for spermine)
when compared to FD (from 1 mg kg1 for putrescine and tyramine to 4 mg kg1 for histamine); MS/MS
method showed higher precision too, with intraday relative standard deviations (RSDs) from 1% to 4%
with respect to those obtained with FD method (from 3% to 17%).
Recovery study was conducted at two different fortification levels and the average ranged from 71% to
93% for all of the studied compounds with RSDs lower than 18%. Matrix-matched standards were used to
counteract matrix effect observed in MS/MS determination. The applicability of the method was demonstrated
by the analysis of biogenic amines in fish obtained from commercials of Valencia
Pesticide residue determination in surface waters by stir bar sorptive extraction and liquid chromatography/tandem mass spectrometry
In this stir bar sorptive extraction (SBSE) method, 16 pesticides were extracted from surface water samples by sorption onto 1 mm polydimethylsiloxane layer coated on a 10-mm-length stir bar magnet. After liquid desorption of the analytes with 1 ml of methanol, the detection was performed on a liquid chromatography-tandem mass spectrometry with a triple quadrupole (QqQ) analyzer using selected reaction monitoring mode via electrospray ionization. Parameters affecting SBSE operation, including sample volume, salt addition, extraction time, stirring rate, and desorption conditions, have been evaluated. The optimized SBSE method required two 50 ml aliquots of surface water samples, one aliquot was added of 30% NaCl and stirred at 900 rpm during 1 h for testing five pesticides with log K o/w∈<∈3, and the other aliquot was directly extracted following the same procedure for the rest of the pesticides with log K o/w∈>∈3. The method was validated in spiked surface water samples at limits of
Simultaneous analysis of eight underivatized biogenic amines in fish by solid phase extraction and liquid chromatography-tandem mass spectrometry
Analysis of biogenic amines on fish tissue is of interest since their accumulation is associated with bacterial contamination and spoilage. A new method using a liquid chromatography coupled to a tandem mass spectrometry (LC-MS/MS) with a triple quadrupole (QqQ) analyzer was developed for the analysis of eight biogenic amines (cadaverine, histamine, phenylethylamine, putrescine, spermine, spermidine, tyramine and tryptamine) in fish samples