Analysis of pilocarpine and isopilocarpine in ophthalmic solutions by normal-phase high-performance liquid chromatography

✍ Scribed by Danny L. Dunn; Britt S. Scott; Edwin D. Dorsey

• Publisher: John Wiley and Sons
• Year: 1981
• Tongue: English
• Weight: 483 KB
• Volume: 70
• Category: Article
• ISSN: 0022-3549
• DOI: 10.1002/jps.2600700427

✦ Synopsis

A normal-phase high-performance liquid chromatographic separation for pilocarpine and isopilocarpine was developed which is suitable for the routine analysis of ophthalmic preparations. The method utilizes a column packed with 5 -~m silica with a mobile phase of hexane-2% ammonium hydroxide in 2-propanol (7030). Peak detection is by UV a t 220 nm. It is suggested that a partition separation mechanism is involved rather than adsorption. A separation factor (a) of 1.17 was obtained with a relative separation (R,) of 2.13. Column lifetimes were typically 6-8 months with daily use. Several standard pilocarpine-isopilocarpine mixtures and five commercially available ophthalmic solutions from different manufacturers were analyzed. The method was specific for pilocarpine and isopilocarpine in the presence of each other and pilocarpic acid and is a significant improvement over the nonspecific colorimetric methods of analysis.