1. Analysis of Ibuprofen in Tablets According to the US Pharmacopoiea using a Varian 920-LC Analytical HPLC and Pursuit ® XRs column By Phuong Truong Varian Australia Pty Ltd 679 Springvale Rd Mulgrave VIC Australia

2. 2 Varian 920-LC

3. 3 Introduction Assays of active pharmaceutical ingredients (API) in medications are common in the pharmaceutical industry Often they are to quantitate the API and contaminants Ibuprofen is a NSAID in widespread use around the world 4-isobutylacetophenone (Ibuprofen related compound C) is a breakdown product of Ibuprofen It can adversely affect the central nervous system The USP requires Ibuprofen related compound C to be determined at < 0.1% per tablet USP proscribe a 250 mm x 4.6 mm ID x 5  m L1 type (C18) column Valerophenone internal standard In this work the recommended column was compared to a 100 x 4.6 x 3  m column

4. 4 Instrumentation Varian 920-LC Analytical HPLC (part no 00100xxx00) Quaternary gradient pump with 4 channel degasser 200 position autosampler with 100  L syringe Thermostated column compartment Diode Array detector Columns Varian Pursuit ® XRs columns feature 100Å silica, high sample loadability, extended pH range, outstanding resolution and excellent column lifetime –Varian Pursuit ® XRs 100 x 4.6 mm x 3  m column (part no AXXXX100X046) –Varian Pursuit ® XRs 250 x 4.6 mm x 5  m column (part no AXXXX100X046)

5. 5 Instrumental Conditions Mobile Phase1% chloroacetic acid in water pH 3/Acetonitrile 40:60 v/v Flow rate2 ml/min Wavelength254 nm TemperatureAmbient

6. 6 Definitions – Resolution and Selectivity (  ) mAU

7. 7 Chromatographic Resolution and Selectivity Resolution R is similar to selectivity but takes into account peak width Baseline resolution is when R=1.5 Capacity factor Selectivity 

8. 8 Standards - Pursuit ® XRs 250 x 4.6 x 5  m Column Ibuprofen and Internal Std with 250 mm x 5  m column

9. 9 Standards – Pursuit ® XRs 250 x 4.6 x 5  m Column Internal Std and Ibuprofen related compound C with 250 mm x 5  m column

10. 10 Results – Pursuit ® XRs 250 x 4.6 x 5  m Resolution (USP > 2.5) Assymetry (USP < 2.5) Selectivity Ibuprofen1.29 I/S in Ibuprofen solution 7.31.001.29 I/S1.06 Ibuprofen related C solution 5.11.011.18

11. 11 Standards – Pursuit ® XRs 100 x 4.6 x 3  m Column Ibuprofen and Internal Std with Pursuit® XRs 100 mm x 3  m column

12. 12 Standards –Pursuit ® XRs 100 x 4.6 x 3  m Column Internal Std and Ibuprofen related compound C with Pursuit® XRs 100 mm x 3  m column

13. 13 Results – Pursuit ® XRs 100 x 4.6 x 3  m Resolution (USP > 2.5) Assymetry (USP < 2.5) Selectivity Ibuprofen1.27 I/S in Ibuprofen solution 5.31.011.29 I/S1.13 Ibuprofen related C solution 4.01.101.18

14. 14 Ibuprofen Tablet Chromatogram of Ibuprofen tablet sample spiked with I/S using a Pursuit ® XRs 100 x 3  m column

15. 15 Spectral Confirmation using PDA Detector

16. 16 Data for Ibuprofen Tablets % of labelled Concentration of Ibuprofen Assymetry of Ibuprofen Assymetry of I/S Resolution between Ibuprofen and Valerophenone I/S 101.9%1.271.085.4

17. 17 Conclusion The Varian 920-LC and Pursuit ® XRs 3  m columns significantly improve throughput of an Ibuprofen assay compared to the USP recommended columns The calculated concentration of Ibuprofen in the tablet complies with USP requirements of nominal + 10% The sensitivity of 920-LC PDA detector ensures the LOD for the Ibuprofen related C compound is 10 fold lower than USP The PDA detector allowed positive confirmation the unknown peak in the tablet was Ibuprofen related compound C (4-isobutylacetophenone)