Application of monolithic columns in pharmaceutical analysis. Determination of indomethacin and its degradation products

✍ Scribed by Petra Žáková; Hana Sklenářová; Lucie Nováková; Renata Hájková; Ludmila Matysová; Petr Solich

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 476 KB
• Volume: 32
• Category: Article
• ISSN: 1615-9306
• DOI: 10.1002/jssc.200900217

✦ Synopsis

Abstract

Comparison of HPLC methods using conventional particle‐based and monolithic columns for determination of indomethacin and its two degradation products, viz. 5‐methoxy‐2‐methylindoleacetic acid and 4‐chlorobenzoic acid, was carried out. Ketoprofen was used as an internal standard for data evaluation throughout the study. Conventional separation was based on analytical column Zorbax SB‐Phenyl (75×4.6 mm; 3.5 μm particles) used with a mobile phase composition of acetonitrile and phosphoric acid 0.2% (50:50, v/v) and isocratic flow at 0.6 mL/min. Three different lengths of Chromolith columns RP‐18e (25×4.6 mm, 50×4.6 mm, and 100×3 mm) were tested with respect to the validation parameters peak asymmetry, resolution, height equivalent to a theoretical plate, repeatability, and after optimisation compared to values obtained using a conventional Zorbax column. The developed methods were used to determine all three compounds in a pharmaceutical formulation – Indobene gel. Chromatographic parameters were comparable to those of a conventional particle‐based column. The analysis time was shortened as expected (retention times were lowered by a factor of two). Moreover, the repeatability of peak areas and retention times obtained with a 50 mm monolithic column was greatly improved (RSD values were lower than 0.40%).