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