Use of near UHPLC column for improved results

This challenging compound has several amine groups and can be problematic to analyze with HPLC. Here a good peak shape is obtained using the Cogent Diamond Hydride 2.o Column. The efficiency is higher on the 2.2µm phase compared to a standard 4µm Column, leading to increased sensitivity. The method conditions are compatible with LCMS as well.

Tizanidine HCI

Method Conditions

Fig. A: Cogent Diamond Hydride 2.o™, 120Å
Fig. B: Cogent Diamond Hydride™, 4µm, 100Å
Catalog Nos.:
Fig. A: 70200-05P-2;
Fig. B: 70000-05P-2
Fig. A: 2.1 x 50 mm
Fig. B: 2.1 x 50 mm
Mobile Phase:
—  A: DI Water / 0.1% Formic Acid (v/v)
—  B: Acetonitrile / 0.1% Formic Acid (v/v)

Time (minutes) %B
0 95
1 95
6 40
7 95

Post time: 3 minutes
Injection vol.: 0.2 µL
Flow rate: 0.3mL/minutes
Detection: UV @ 230 nm
Sample: 4mg strength Tizanidine HCl tablet was ground and weighed in a 10mL Volumetric Flask. A portion of 50/50 Solvent A / Solvent B diluent was added and the flask was sonicated 10 minutes. It was then diluted to mark and filtered with a 0.45µm Nylon Syringe Filter (MicroSolv Tech Corp.).
t0: 0.6 minutes

Note: Tizanidine is a centrally acting A2-Adren- Ergic agonist used to treat spasms, cramping, tightness of muscles, and related conditions. It is available under the trade name Zanaflex® as well as generic versions.


Tizanidine HCI Method Transfer pdf  Download File