ABSTRACT
A matrix solid phase dispersion ( MSPD) method was developed for the simultaneous preparation of samples of 15 mycotoxin biomarkers including deoxynivalenol, aflatoxins and zearalenone from eggs, which were subsequently determined by liquid chromatography-electrospray ionization tandem mass spectrometry ( LC-ESI-MS/MS) under the multiple reaction monitoring ( MRM) mode. For the analysis, the samples were first mixed with C18 particles and loaded into an empty column, then 20 mL of acetonitrile/methanol (1:1, V/V) containing 1 mmol/L ammonium formate was used to elute the sample. The eluent was then dried with nitrogen flow and redissolved into the mobile phase. After filtration, samples were brought into vials and used for analysis. Different from other methods, no extra complicated purification and centrifugation steps were required in the procedure of MSPD. This method had good linearity in the range of 0. 2-100 ng/mL, with the correlation coefficient (r2) greater than 0. 9931. The limits of detection (LODs, S/N=3) and limits of quantification ( LOQs, S/N=3 ) of this method were 0. 05-2 μg/kg and 0. 2-4 μg/kg respectively. Comprehensive extraction recoveries of the 15 compounds ranged from 61% to 90%.
ABSTRACT
A matrix solid phase dispersion extraction_dispersed liquid phase microextraction_gas chromatography_mass spectrometric method has been developed for the determination of three pyrethroids ( tetramethrin, permethrin and deltamethrin) in soil. The optimal conditions for the analysis were as follows. About 0. 5 g soil and 1. 5 g C18 solid phase extraction powder were grinding for 5 min. The mixture was eluted with 10 mL of acetone. The eluent was concentrated to 0. 4 mL, and then mixed with 20 μL of tetrachloromethane and 5. 0 mL of ultrapure water to form a homogeneous cloudy solution. The emulsion was broken by centrifugation. About 1 μL of sediment was injected and analyzed directly by GC_MS. Good linearities for three pyrethroids were ranged from 5 to 200 μg/kg (r2≥0. 9989), and recoveries at three spiked levels were ranged from 86 . 5% to 108 . 0% with RSDs less than 7 . 8%. The LODs of three pyrethroids were 1. 00-1. 48 μg/kg. This method can meet the determination of trace pyrethroids in soil.
ABSTRACT
En este trabajo se desarrolló y validó un método simple, ambientalmente amigable y efectivo, para la extracción y cuantificación de cipermetrina en muestras de bovino (hígado, grasa perirrenal y músculo) utilizando dispersión de matriz en fase sólida (MSPD) y cromatografía de gases con detector de ionización de llama (GC-FID). Diferentes parámetros del método se evaluaron, tales como el dispersante, solvente de extracción y volumen de solvente. Los mejores resultados para la extracción de cipermetrina por MSPD fueron: 0,20 g de muestra macerados con 0,80 g de silica gel y extraídos con 5,00 mL de acetona. El procedimiento propuesto fue validado mostrando comportamiento lineal en el intervalo de 10,20-400,40 µg/L (R²=0,9988). Los límites de detección y cuantificación fueron 2,00 y 5,70 µg/L respectivamente, con una desviación estándar relativa de 0,0875 (n=5). Este método permite determinar cipermetrina hasta niveles traza en muestras de tejido animal, con una recuperación de 98,96%.
In the present study a simple, effective and environmentally friendly method was developed and validated for the extraction and quantification of cypermethrin in animal tissue (meat, fat and liver) based on matrix solid-phase dispersion (MSPD) and gas chromatography with flame ionization detector (GC-FID). Different parameters of the method were evaluated, such as dispersant, extractive solvent and solvent volume. The best results for the extraction of cypermethrin by MSPD were 0.20 g of sample with 0.80 g of silica gel and 5.00 mL of acetone as eluting solvent. The proposed procedure was validated showing linear behavior in the interval of 10.20 to 400.40 µg/L (R²= 0.9988). Detection and quantification limits ranged from 2.00 and 5.70 µg/L respectively, with a standard deviation of 0.0875 (n=5). This method enables to determine cypermethrin at trace level in animal tissue samples, with a recovery of 98.96%.
Neste trabalho foi desenvolvido e validado um método verde para extração e quantificação de cipermetrina em amostras de fígado, gordura perirrenal e músculo em gado bovino, por meio da técnica de dispersão de matriz em fase solida (MSPD) e cromatografia de gases com detecção de ionização de chama (GC-FID). Foram avaliados diferentes parâmetros do método, como dispersante, extração com solvente e volume de solvente. Os melhores resultados para a extracção da cipermetrina por MSPD foram 0.20 g da amostra macerada com 0.80 g de gel de sílica e extraiu-se com 5.00 mL de acetona. O método proposto foi validada mostrando um comportamento linear na gama testada (10.20-400.40 µg/L) com R² de 0.9988. Os limites de detecção e de quantificação foram 2.00 e 5.70 µg/L, respectivamente, com um desvio padrão de 0.0875 (n = 5). O método proposto neste trabalho permitiu determinar níveis traça da cipermetrina em amostras de tecidos animai, com uma recuperação de 98.96%.
ABSTRACT
An analytical method based on high performance liquid chromatography tandem mass spectrometry has been developed for the simultaneous determination of 20 anti-obesity drugs ( fenfluramine, phenylpropanolamine, sibutramine, sertraline, rimonabant, bupropion, citalopram, fluoxetine, benfluorex, topiramate, zonisamide, caffeine, phenolphthalein, emodin, indapamide, bumetanide, torasemide, triamterene, orlistat, phenformin). that were extracted from various weight-loss functional foods by ethanol-acetone(7:3, V/V)and purified by primary secondary amine (PSA) and octadecyltrimethoxysilane(ODS) under ultrasonication. The analysis was carried out on HPLC-MS /MS by electrospray ionization using multiple reaction monitoring after the chromatographic separation on Waters Atlantis T3 (3 μm, 150 mm × 2. 1 mm) column. Identification was achieved by the retention time and the ion ratio, quantification was done by the external standard method. The limits of detection for the appetite suppressants were 0. 05-3. 0 mg/kg. The mean recoveries at the three spiked levels were 67 . 1%-101 . 4%, with the intra-day precision less than 10%and the inter-day precision less than 15%. The method is reliable, accurate, reproducible and suitable for the determination of the anti-obesity drugs in different weight-loss functional foods.
ABSTRACT
An efficient method is provided to detect simultaneously some important veterinary drugs from different classes in highly complex animal tissue matrix.This method using matrix solid-phase dispersion (MSPD) and high performance liquid chromatography (HPLC) with diode array detection (DAD) is developed to effectively determine two fluoroquinolones (enoxacin and lomefloxacin),two sulfonamides (sulfanilamide and sulfamethoxazole) and one tetracycline (tetracycline) simultaneously in porcine tissues.In the process,MSPD methodology was used to treat samples,washed by n-hexane to remove lipid,eluted the analytes with acetonitrile-dichloromethane (1∶1,v/v).Solvent acetonitrile and solvent acetic acid (0.1％) were combined in a gradient.HPLC-DAD analysis of the tissue samples was performed within 15min at a flow rate of 1.0mL/min.The results showed that a recovery at 0.1,0.5 and 1.0 μg/g fortification levels ranged from 80.6％ to 99.2％ with satisfactory relative standard deviations (RSDs) (below 6.1％.n=3) and the limits of quantitation (LOQ) ranged from 7 μg/kg to 34 μg/kg in porcine tissues.Utilization of the method in successfully simultaneous analysis of porcine tissue incurred with veterinary drug multiresidues is described.