Introduction

A Cogent Phenyl Hydride™ HPLC column was used to separate chlorothiazide, hydrochlorothiazide, and 4-amino-6-chloro-1,3-benzenedisulfonamide in a single chromatographic analysis. The three compounds are structurally related and contain sulfonamide functionality, making chromatographic selectivity an important consideration for their separation.

The method separates the related compound from chlorothiazide and hydrochlorothiazide and demonstrates the selectivity of the Phenyl Hydride stationary phase for this group of closely related analytes.

Peaks:   1.  4-Amino-6-chloro-1,3-benzenedisulfonamide  2.  Chlorothiazide 3. Hydrochlorothiazide

Method Conditions
Column: Cogent Phenyl Hydride™, 4 μm, 100 Å
Catalog No. : 69020-15P
Dimensions : 4.6 x 150 mm

Mobile Phase : 80:20  DI Water /   Acetonitrile / 0.1% formic acid
Injection vol. :  1μL
Flow rate : 1.0 mL/minute
Detection : UV @ 224 nm

Sample Preparation : Equal volumes (100 µL) of chlorothiazide (1.55 mg/mL), hydrochlorothiazide (1.56 mg/mL), and 4-amino-6-chloro-1,3-benzenedisulfonamide (1.57 mg/mL) stock solutions were combined and diluted to 1.0 mL with 50:50 ACN:DI water, yielding final concentrations of 0.155, 0.156, and 0.157 mg/mL, respectively.