|
|
Note: Because silanols on the silica surface are substituted with Si-H, water is not retained by the stationary phase
and analyses are very reproducible.
|
HPLC Application Sheet
Gradient Equilibration: Rapid, increased throughput
|
Discussion
The Cogent TYPE-C Silica based columns which are bonded to a silica-hydride surface, equilibrate in 1/25th time it
normally takes to equilibrate a high quality, Type-B silica based HPLC Column. This allows a much higher throughput
and more data analysis. This also lends itself to the use of “ballistic gradients” for high thoughput screening.
Method Conditions
| Column |
Cogent Bidentate C18™, 4µm, 100A |
| Catalog No. |
40018-75P |
| Dimensions |
4.6 x 75 mm |
| Gradient |
0-3 minutes ACN/Water (50:50)
3-18 minutes to 100% ACN
18-23 minutes to 50:50 ACN/WAter
|
| Flow rate |
0.5 mL/minute |
| Injection Volume |
1 µL |
| Samples |
Benzene, Napthalene, Phenanthrene, Antrhacene, Pyrene dissolved in the mobile phase |
| Detection |
UV 254 nm |
Equilibration of Type-C Silica Stationary Phases
Reversed Phase Mode
The sample consists of five components that elute in the following order: benzene; naphthalene; phenanthrene;
anthracene; and pyrene.
| Flow rate for all tests: |
0.5 mL/min |
| All columns: |
4.6 x 75 mm |
| Gradient program: |
0-3 min ACN/water (50:50)
3-18 min to 100% ACN
18-23 min 100% ACN
Equilibration to 50:50 ACN/water |
Figure Bidentate C18 (Column 1)
Frame A: Equilibration time 25 min
Frame B: Equilibration time 1 min
| |
Retention Time (min) |
| Solute/Equilibration Time |
25 min |
10 min |
1 min |
| Benzene |
7.30 |
7.35 |
7.25 |
| Naphthalene |
11.10 |
11.07 |
11.01 |
| Phenanthrene |
14.39 |
14.37 |
14.37 |
| Anthracene |
14.81 |
14.80 |
14.80 |
| Pyrene |
16.52 |
16.51 |
16.56 |
|
Figure Bidentate C18 (Column 2)
Frame A: Equilibration time 25 min
Frame B: Equilibration time 1 min
| |
Retention Time (min) |
| Solute/Equilibration Time |
25 min |
10 min |
1 min |
| Benzene |
7.30 |
7.27 |
7.25 |
| Naphthalene |
11.01 |
11.00 |
11.01 |
| Phenanthrene |
14.32 |
14.31 |
14.37 |
| Anthracene |
14.75 |
14.75 |
14.80 |
| Pyrene |
16.47 |
16.50 |
16.55 |
|
Figure Bidentate C8
Frame A: Equilibration time 25 min
Frame B: Equilibration time 1 min
| |
Retention Time (min) |
| Solute/Equilibration Time |
25 min |
10 min |
1 min |
| Benzene |
5.58 |
5.57 |
5.52 |
| Naphthalene |
8.18 |
8.17 |
8.09 |
| Phenanthrene |
10.31 |
10.33 |
10.25 |
| Anthracene |
10.53 |
10.55 |
10.47 |
| Pyrene |
11.38 |
11.40 |
11.33 |
|
Figure UDC Cholesterol
Frame A: Equilibration time 25 min
Frame B: Equilibration time 1 min
| |
Retention Time (min) |
| Solute/Equilibration Time |
25 min |
10 min |
1 min |
| Benzene |
5.49 |
5.45 |
5.43 |
| Naphthalene |
9.00 |
8.97 |
8.99 |
| Phenanthrene |
12.70 |
12.65 |
12.68 |
| Anthracene |
13.03 |
13.00 |
13.02 |
| Pyrene |
15.08 |
15.03 |
15.00 |
|
|
