TABLE OF CONTENTS - BGB Analytik AG

LC and LC/MS
ZORBAX Rx
ZORBAX Rx
Analysis of Diazepam on Rx-C18
Column: ZORBAX Rx-C18
880967-302
3.0 x 250 mm, 5 µm
Mobile Phase: 35% H2O: 65% MeOH
Flow Rate: 0.5 mL/min
622 www.agilent.com/chem/supplies
• Rx-C18 is recommended for alternate selectivity at low pH relative to Eclipse XDB-C18
and StableBond SB-C18; for higher temperature applications, StableBond is recommended.
This column has a higher carbon load than SB-C18 columns (12% vs. 10%).
• Rx-C18 offers high stability and good peak shape for low pH applications.
• Rx-C18 is manufactured using dimethyloctadecylsilane, is non-endcapped and
provides excellent stability up to pH 8.
• Rx-C8 is the same product as SB-C8.
Column Specifications
Bonded Phase
Pore
Size
An Rx-C18 column is used for this USP
analysis of diazepam and the internal
standard ethylparaben. The Solvent
Saver 3.0 mm i.d. Rx-C18 column
reduces solvent usage by 60% over
what would be used if the analysis were
done on a 4.6 x 250 mm column.
Surface
Area
Temp.
Limits
1. Ethylparaben
2. Diazepam
pH
Range* Endcapped
1
0.0 2.5
Time (min)
5.0 7.5
2
Carbon
Load
ZORBAX Rx-C18 80Å 180 m2/g 60°C 2.0-8.0 No 12%
ZORBAX Rx-C8 80Å 180 m2/g 80°C 1.0-8.0 No 5.5%
Specifications represent typical values only.
*At pH 6-9 highest column stability for all silica based columns is obtained by operating at temperatures < 40°C and using
lower buffer concentrations in the range of 0.01 - 0.02M.
LCRX001