Page 50 - BR20828_E Accucore 0713S

2 Peak efficiency comparison
Figure 1 illustrates the separation of ibuprofen and valerophenone on a Accucore XL C18 4 μm
HPLC column and a fully porous C18 5 μm column using the same isocratic method based on the
USP monograph [2]. Efficiency for both compounds improved by more than 70% when using the
Accucore XL HPLC column compared to the fully porous column (Table 1). This improvement in
peak efficiency results in increased signal to noise ratio (112% on average) for exactly the same
amount injected on column, representing a dramatic improvement in analysis sensitivity.
The backpressure for the Accucore XL C18 4 μm HPLC column was measured at 312 bar, and the
5 μm fully porous column backpressure was measured at 239 bar. Therefore, the improvement in
analysis sensitivity is gained with a small increase in backpressure, which is still within the
operating limits of a conventional HPLC system.
Figure 1: Chromatogram of valerophenone (1) and ibuprofen (2) analyzed using an Accucore XL C18 4 μm HPLC
column (bottom trace) compared to a fully porous C18 5 μm column (top trace)
Experimental conditions: columns – 150 × 4.6 mm; mobile phase – water with phosphoric acid, pH 2.5 /
acetonitrile (66.3:33.7 v/v); flow rate – 2 mL/min; column temperature – 30 °C; UV detection – 214 nm;
injection volume – 5 μL
mAU
Time (min)
-5
-2.5
0.0 2.5
0
2.5
5.0
7.5
10.0
12.5
15.0
17.5
20.0
22.5
25.0
27.5
30.0
5.0 7.5 10.0 12.5 15.0 17.5 20.0 22.5 25.0 27.5
1
2
30.0
mAU
Time (min)
-5
-2.5
0.0 2.5
0
2.5
5.0
7.5
10.0
12.5
15.0
17.5
20.0
22.5
25.0
27.5
30.0
5.0 7.5 10.0 12.5 15.0 17.5 20.0 22.5 25.0 27.5
1
2
30.0
Compound
Plates (USP) Signal-to-Noise Ratio
Accucore
XL
Fully
Porous
%
improvement
Accucore
XL
Fully
Porous
%
improvement
Valerophenone 19532 11218 74 908 462 96
Ibuprofen 18274 10538 73 1202 534 125
Table 1: Efficiency and signal-to-noise ratio data for valerophenone and ibuprofen