Bio-Rad Aminex Organic Acid and Alcohol Analysis Columns - Manual (Page 7)

.300” .08” .210” .09”
Valco Parker
Fig. 1. Bio-Rad’s resin-based columns are manufactured using Parker end-fittings. Reverse
nuts and ferrules are supplied with the columns and must be used to attach the column to the HPLC
system if the system is not already equipped with Parker 1/16” reverse nuts or the equivalent.
Section 5
Operating Parameters
At this time the HPLC system should have been purged with priming solvent
followed by the proper mobile phase, the guard column should have been
equilibrated, and the analytical column should be attached. The flow rate should be
at 0.2 ml/min.
5.1 Flow Rate
Ramp up the flow rate slowly on Aminex columns. Increase the flow rate of a
heated column only after the column has come up to operating temperature. Do
not operate high temperature Aminex carbohydrate columns (Aminex HPX-87C,
Aminex HPX-87P, Aminex HPX-87N, or Aminex HPX-87K columns) above
0.3 ml/min while at ambient temperatures. First, allow the column heater to heat
the column while maintaining slower flow rates; then increase to the operating flow
rate when the column has arrived at the recommended operating temperature. Do
not allow the flow rate to exceed the maximum rate specified for the column, but
even then, columns should not be operated at maximum flow rates for extended
periods. Optimum flow rates are specified in published methods, and also flow
rates can be selected based on the quality of the resolution. Many times, slower
flow rates improve resolution. Typically, 300 mm long (30 cm) Aminex columns
operate best at 0.5 to 0.7 ml/min, when back pressure on the column is below
maximum levels. Back pressures may increase with column age, so let back
pressure be the primary determinant of flow rate. Standard flow rate for the Aminex
HPX-87C, Aminex HPX-87H, and other Aminex HPX-87 series columns is
0.6 ml/min.
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