Waters ACQUITY APC Columns - Manual (Page 4)

4
ACQUITY APC Columns
b. Calibration
Whenever replacing a single column of a complete column bank, generate a new calibration curve to
ensure the reproducibility of the application. Figure 3 shows typical calibration curves for each column.
The calibration curves were obtained with polystyrene standards. Figure 4 shows the expected linear
range based on the calibration data.
100
1,000
10,000
100,000
1,000,000
10,000,000
0.50 1.00 1.50 2.00
Po
ly
st
yrene
Mole
cula
r We
ig
ht
(D
a)
Elution volume (mL)
ACQUITY APC
XT 450 ACQUITY APC
XT 200 ACQUITY APC
XT 900 ACQUITY APC
XT 125 ACQUITY APC
XT 45
Figure 3. Calibration Curves for ACQUITY APC XT and ACQUITY APC AQ Columns (4.6 x 150 mm) Using Polystyrene Standards.
10 10 1 10 2 10 3 10 4 10 5 10 6 10 7
Effective Molecular Weight Range
ACQUITY APC (AQ/XT) 45
ACQUITY APC (AQ/XT) 125
ACQUITY APC (AQ/XT) 200
ACQUITY APC (AQ/XT) 450
ACQUITY APC (XT) 900
Figure 4. Effective Molecular Weight Range for ACQUITY APC Columns.
c. Useable Flow-Rate Ranges
Excessive mobile-flow rates can create backpressure that can damage the column packing material.
For any given particle size, as the pore volume increases, the base particle loses mechanical strength
due to the reduction in particle wall thickness surrounding the open pore. Table 3 shows the maximum
flow rate recommendation for a single column for each pore size, independent of column length. When
connecting multiple columns in series, the column that specifies the lowest flow rate will dictate the
maximum flow rate for the column bank. Higher viscosity solvents will limit the flow rate due to flow
restriction. Table 4 provides viscosity data for common solvents.