Analytical Sciences


Abstract − Analytical Sciences, 19(7), 1079 (2003).

Simultaneous Determination ofTheophylline and Caffeine by Proton Magnetic Resonance Spectroscopy UsingPartial Least Squares Regression Techniques
Zahra TALEBPOUR,* SaeedMAESUM,** Mehdi JALALI-HERAVI,** and MojtabaSHAMSIPUR*** 
*Department of Chemistry, TarbiatModarres University, Tehran, Iran
**Department of Chemistry, SharifUniversity of Technology, Tehran, Iran
***Department of Chemistry, RaziUniversity, Kermanshah, Iran
A 1H-NMR procedure based on ananalysis of its data by a multivariate calibration method was conducted forthe simultaneous determination of theophylline and caffeine in syntheticand real samples. Partial least squares regression (PLS) was chosen as thecalibration method. The methyl signals of theophilline at 3.36 and 3.54ppm that overlapped with those of caffeine were significant characteristicswhich were employed in this study for their analyses. The proposed methodwas successfully applied to recovery studies of theophylline and caffeinefrom real tablet samples.