Page 15 - Shimadu Consumables Catalog

Shim-pack Velox SP-C18

Shim-pack Velox C18 is a traditional end-capped C18-bonded phase which offers the highest hydrophobic
retention of any Shim-pack Velox phases and is applicable to a wide range of applications such as
pharmaceutical, food, environmental and clinical and neutrals at moderately low and mid-range pH.
S i
General purpose column for reversed-phase chromatography O
Highest hydrophobic retention among Shim-pack Velox series
Compatible with moderately acidic to neutral mobile phases (pH 2-8)

Method Transfer for Cyanocobalamin Analysis within the USP Allowable Adjustment

The assay of cyanocobalamin (a synthetic form of vitamin B12) with 5 µm fully-porous ODS column described in the USP
monograph is transferred to a new method with Shim-pack Velox C18 2.7 µm column, within USP allowable adjustments.
Analytical time and solvent consumption can be saved with transferred methods while meeting the requirements of system
suitability.

USP requirement of Chromatography <621>
When the column size is changed, the following conditions should be met;
1) L/dp ratio : within -25 % to +50 %
or
Number of theoretical plates (N): within -25 % to +50 % (For SPP)
2) Flow rate : *Based on particle size and internal diameter and ±50%
L : Column length
2 dp : Particle size
dc2 × dp1
* F2 = F1 ×
2
dc1 × dp2 F : Flow rate
dc : Internal diameter of the column

Original Method
Column : Shim-pack VP-ODS (5 µm, 4.6×150 mm)
Flow rate : 0.5 mL/min
Injection Volume : 100 µL
Column temp. : 25 °C
Detection : UV 361 nm

Faster Method
Column : Shim-pack Velox C18 (2.7 µm, 4.6×100 mm)
Flow rate : 0.50 mL/min
Injection Volume : 67 µL
Column temp. : 25 °C
Detection : UV 361 nm

Optimized Method
Column : Shim-pack Velox C18 (2.7 µm, 4.6×100 mm)
Flow rate : 0.93 mL/min
Injection Volume : 67 µL
Column temp. : 25 °C
Detection : UV 361 nm

System suitability test
Column L/dp Flow rate (mL/min) N result (Requirement:
%RSD < 2.0 %)
VP-ODS tR: 0.025 %
(5 µm, 4.6×150 mm) 30,000 0.50 5,244 Area: 0.175 % (n=6)
9,497 tR: 0.035 %
0.50
Velox C18 37,037 (+81 %) Area: 0.103 % (n=6)
(2.7 µm, 4.6×100 mm) (+23 %) 4,466 tR: 0.084 %
0.93
(-15 %) Area: 0.220 % (n=6)

Pg A-11