Determination of Pesticide Residues in Red Wine by QuEChERS Extraction, Quick QuEChERS Cleanup and LC–MS-MS Detection
UCT
Red wine is a challenging matrix that contains organic acids, sugars, phenols and pigments such as anthocyanins. This application note describes a simple, fast, novel and effective method to clean up red wine co-extractives.
Extraction Procedure
a) Add 10 mL red wine to 50 mL tube (RFV0050CT)
b) Add 10 mL acetonitrile, vortex 30 s
c) Add salts from Mylar pouch (ECQUUS2-MP)
d) Shake vigorously for 1 min
e) Centrifuge at 5000 rpm for 5 min
f) Supernatant is ready for cleanup
Quick QuEChERS Cleanup
a) Load 1 mL supernatant with disposable syringe
b) Push the supernatant slowly through the cartridge (ECPURMPSMC)
c) Collect 0.5 mL extract into 2 mL autosampler vial
d) Add triphenyl phosphate as internal standard
LC–MS-MS Instrumentation
LC: Thermo Accela 1250 pump
- Column: SepaxHP-C18, 2.1 × 100 mm, 3 µm, 120 Å
- Guard: Restek C18 2.1 × 20 mm, 3 µm
- Column temperature: Ambient
- Injection: 10 µL at 15° C
- Mobile phase: A: 0.1% formic acid in water; B: 0.1% formic acid in methanol
- Gradient: 0 min: 95% A; 1 min: 95%; 3 min: 50% A; 8 min: 5% A; 14 min: 5% A; 14.2 min: 95% A; 16 min: 95% A
- Flow rate: 200 µL/min
MS-MS: Thermo TSQ Vantage
- Ion source: Heated ESI positive, 350 ºC
- Spray voltage: 3000 V
- Sheath gas: N2 at 40 psi
- Auxiliary gas: N2 at 10 psi
- Collision gas: Ar at 1.5 mTorr
Results:
Recoveries ranged from 81.6 to 112.2% with RSD less than 10.8% achieved for red wine samples fortified with 10, 50 and 100 ng/mL pesticides.
Figure 1: Top: Quick QuEChERS cartridges before and after cleanup of 1 mL red wine extract; Bottom: Red wine extract before (left) and after (right) Quick QuEChERS cleanup.
UCT, LLC
2731 Bartram Road, Bristol, Pennsylvania 19007, USA
tel. 800.385.3152
Email: methods@unitedchem.com
Website: www.unitedchem.com
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