Page 51 - BR20828_E Accucore 0713S

3 Sensitivity comparison with gradient mobile phase conditions
In Figure 2 the analysis performance of an Accucore XL C8 4 μm HPLC column is compared to
that of a fully porous C8 5 μm using gradient mobile phase conditions, and maintaining all other
experimental conditions for the two columns. The peak widths for the seven triazines narrowed
significantly (on average by 29%) when using the Accucore XL HPLC column compared to the
fully porous column (Table 2). As a result, the signal-to-noise ratio increased by 140% on average
for exactly the same amount injected on column, significantly improving analysis sensitivity
(Figure 3). Additionally, the resolution between the critical pair (peaks 5 and 6) on the fully porous
column was 1.92, which improved by 54% to 2.95 with the Accucore XL C8 HPLC column.
The backpressure for the Accucore XL C8 4 μm HPLC column was measured at 215 bar, and the
5 μm fully porous column backpressure was measured at 165 bar. The improvement in
performance was gained with a small increase in backpressure, which was still within the operating
limits of a conventional HPLC system.
Figure 2: Chromatogram of simazine (1), simetryn (2), atrazine (3), prometon (4), ametryn (5), propazine (6), and
prometryn (7) 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 – C18, 150 × 4.6 mm; mobile phase – water and acetonitrile; gradient – 20%
to 60% acetonitrile in 10 min; flow rate – 1.5 mL/min; column temperature – 25 °C; UV detection – 220 nm;
injection volume – 5 μL
mAU
Time (min)
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0
0.0 1.0
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2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0
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11.0
mAU
Time (min)
-20
0
0.0 1.0
25
50
75
100
125
150
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2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0
1
2
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11.0