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Determination of Beta Agonist Drugs Residue in Animal Tissues
Using 150mg 6mL HyperSep Retain-CX
(Part Number: 60107-311)
Sample Preparation
Extract 20g from liver sample using CAN
Dry and spike with appropriate standard (10nmol) e.g.
clenbuterol hydrochloride, salbutamol, cimaterol,
ractopamine etc
Prepare solutions at 1, 2, 5, 10 and 100µg/L
Condition HyperSep Retain-CX Extraction Column
1 x 5mL CH
3
OH
1 x 5mL H
2
O (mmol/L HCl)
Apply Sample
Load sample at 1 to 2mL/minute
Wash Column
1 x 5mL H
2
O
1 x 5mL CH
3
OH
Dry column using N
2
Elute Melamine
1 x 5mL of CH
3
OH containing 4% NH
4
OH
Collect eluate at 1 to 2mL/minute
Dry under nitrogen
Derivatize
Heat the glass tube with stopper in oven at 50°C for a
moment to remove water
Add 100µL toluene and 100µL BSTFA* (with 1% TMCS)*
Mix/vortex
Overlay with nitrogen and cap
Mix/vortex
Heat at 80°C for 1 hour
Cool and add 300µL of toluene
* Part number TS-38831
Analysis
Inject 5 on to GC/MS
Recommended GC Column
Part Number
TraceGOLD TG-5SilMS 30m x 0.25m x 0.25µm
26096-1420
Multiresidue Analysis in Cereal Grains for LC/MS/MS or GC/MS
Using QuEChERS Methodology
(Part Number: 60105-211 and 60105-220)
Pesticide Standards
Prepare individual pesticide stock solutions (2,000 to
5,000µg/mL) in ethyl acetate or ACN and store at -18°C
Prepare two composite pesticide stock solutions, MIX-1
and MIX-2 at 10µg/mL in ACN
Add 0.1% acetic acid to prevents degradation of
base-sensitive analytes in ACN
Isotopically Labeled Internal Standards
Prepare at 5µg/mL in acetone
atrazine (ethylamine-d5)
carbofuran (ring-13C6)
dimethoate (o,o-dimethyl-d6)
2,4-DDT (ring-13C6)
-HCH (13C6)
parathion (diethyl-d10)
QC Working Solution
trans-permethrin (phenoxy-13C6) (1 and 5µg/mL in acetone)
Sample Preparation
Thoroughly homogenize a sample of grain products using
a laboratory mill to a flourlike consistency
Place appropriate weight* of sample into the 50mL
centrifuge tube (60105-211)
Add 10mL of deionized water (15mL for rice) and
10mL of ACN
Add 200µL of ISTD standard solution
Mix/vortex tube to disperse sample and standard for
1 hour using a wrist action shaker
Centrifuge at rcf >3,000 for 10 minutes
Sample Cleanup
Transfer a 1mL aliquot to a 2mL tube (60105-220)
Mix/vortex for 30 seconds
Centrifuge for 5 minutes
Transfer 300µL of the supernatant into the chamber of a
filter vial and add 30µL 1µg/mL QC solution
Mix thoroughly
Change to Transfer 125µl of extract into a vial and cap
and store overnight at 250°C
Press the 0.2µm polyvinylidine fluoride (PVDF) filter of the
Mini-UniPrep to filter the extract for the LC/MS/MS analysis
Add 30µL of QC standard solution
Sample is now ready for analysis
Analysis LC or GC/MS
Injection appropriate volume on to LC/MS or GC/MS
* Corn 2.5g, Oat 3.5g, Rice 5.0g, Wheat 5.0g
Food Safety
Applications