biocommaIntroduction
Ochratoxins are metabolites of certain Aspergillus andPenicillium fungi. Ochratoxin A, B, and C differ in chemicalstructures. Ochratoxin A (OTA) is the most toxic and widelycontaminated. Once ingested through contaminated agriculturalproducts, OTA is absorbed through the gastrointestinal systemand causes serious diseases.
Biocomma established a high-throughput LC method usingCopure® 229 Multifunctional Purification Plate for detectionof OTA in soybean with good recovery and stability for yourreference. The recoveries were 90-110%, and CV valuebetween wells was less than 5% at both 4 ng/g and 8 ng/gconcentrations.
Experiment
Extraction
Weigh 5 g of sample into a 50 mL centrifuge tube. Add 20 mLof acetonitrile-water solution (84:16) and vortex for 15 min tomix well. Centrifuge at 6000 r/min for 5 min. The supernatant isready for purification.
Purification (Copure® 229 Multifunctional PurificationPlate)
Place a 24 well purification plate on a 24 well collection plate.Add 6 mL of supernatant to the purification plate. Place the 24well purification plate and the collection plate on the Biocomma®Positive Pressure 24 Processor. Turn on the gas. Make surethe wells of purification plate are positioned directly underthe gas vent. Adjust the gas flow until all the sample filter intothe collection plate. Pipette 4 mL of sample to a clean tube.Evaporate sample to dryness at 40 ℃ and redissolve by 1 mLof initial mobile phase. Vortex for 30 seconds to dissolve theresidue. After filter by 0.22 μm microporous membrane, thesample is ready for analysis.
Instrument Conditions
Equipment: UltiMate 3000 (Thermo Fisher Scientific) with FLDdetector.
Chromatographic column: Agilent ZORBAX C18 (4.6 mm×250mm,5 μm)
Mobile phase: A: 2% Acetic acid water, B: AcetonitrileFlow rate: 1.0 mL/min
Column temperature: 30 ℃
Injection volume: 10.0 μL
Detection wavelength: excitation wavelength 333 nm, emissionwavelength 460 nm
Detector: FLD
Table 1. Gradient Elution Program
Results
Table 2. Spiked Ochratoxin A in Soybean Recovery
Based on Figure 1, the impurities are obviously absorbed byCopure® 229 Multifunctional Purification Plate. There are nointerference peaks next to the target peak, so the quantificationis more accurate. Based on Table 2, the recovery rates ofOchratoxin A in the 24 wells are all between 90-110%, and theCV value of the recovery rate between wells is less than 5%,which meet the standard of the experimental requirements.
Ordering Information
