Polyether antibiotics, such as
Monensin, Narasin and Salinomycin, in raw
material, premix, liquid supplements and final
feeds are best quantified using HPLC with
post-column derivatization. Because of selectivity
of post-column reaction almost no sample cleanup
is needed.
LC Conditions:
Flow
Rate:
0.7 mL/min, column
temperature 40 °C, injection volume 10 µL
Mobile Phase:
Methanol/5% Acetic
Acid in Water (90:10), isocratic
Post-column
conditions (non-metallic
post-column derivatization system is required):
Reagent 1:
Concentrated Sulfuric
acid / Methanol
(4:96 v/v)
Reactor 1:
Ambient, 0.1 mL
Reagent 2:
60 g of Vanillin (or
p-dimethylaminobenzaldehyde) in 950
mL
of Methanol
Reactor 2:
90 °C, 1.4 mL
Reagents Flow Rate:
0.3 mL/min
Note: Using 2-reagent system for this
application greatly extends reagents life.
One-reagent method and post-column
derivatization system are also available.
Detection:
UV-Vis detector:
Vanillin =520
nm,
DMAB =450 nm
POLYETHER
ANTIBIOTICS CATALOG INFORMATION
CATALOG NO.
DESCRIPTION
2381750
Polyether
reversed-phase column, C18,
4.6 × 250 mm
=520
nm, 
