 
            
        This is an Application Brief and does not contain a detailed Experimental section.
This application brief highlights the analysis of caffeine metabolites using XBridge Phenyl columns.
 
            
        | Columns: | XBridge Phenyl, 4.6 x 100 mm, 3.5 μm p/n: 186003334 | 
| Mobile phase A: | H2O | 
| Mobile phase B: | ACN | 
| Mobile phase C: | 100 mM NH4HCO3 | 
| Flow rate: | 1.0 mL/min | 
| Injection volume: | 10 μL | 
| Sample: | Caffeine (10 μg/mL), Theobromine (10 μg/mL), 1-Methyl xanthine (10 μg/mL), 1,3-Dimethyluric Acid (10 μg/mL), 1,7-Dimethyl xanthine (10 μg/mL), 1,7-Dimethyluric Acid (10 μg/mL) in H2O/NH4HCO3 (90/10) | 
| Column temp.: | 30 °C | 
| Sampling temp.: | 15 °C | 
| Detection: | UV @ 280 nm | 
| Sampling Rate: | 5 points/sec | 
| Filter Response: | 0.2 | 
| Instrument: | Alliance 2695 with 2996 PDA | 
| Time(min) | %A | %B | %C | 
|---|---|---|---|
| 0 | 89 | 1 | 10 | 
| 9 | 66 | 24 | 10 | 
| 10 | 89 | 1 | 10 | 
| 20 | 89 | 1 | 10 | 
 
            
        WA60187, June 2007