caa a22 4500 477126014 CHVBK 20180405111649.0 cr unu---uuuuu 170330e19970901xx s 000 0 eng 10.1023/A:1012198605891 doi (NATIONALLICENCE)springer-10.1023/A:1012198605891 Simultaneous Quantification of an Enantiomer and the Racemic Compound of Ibuprofen by X-ray Powder Diffractometry [Elektronische Daten] [Neelima Phadnis, Raj Suryanarayanan] Purpose. An X-ray powder diffractometric method was developed for the simultaneous quantification of the relative amounts of the racemic compound (±) of ibuprofen (I) and S(+)-ibuprofen (II), when they occur as a mixture. Methods. The X-ray powder diffraction patterns of I and II show pronounced differences. This formed the basis for the determination of the relative amounts of I and II when they occur as a mixture. X-ray lines with d-spacings of 14.41 and 4.37 Å were unique to I and II, respectively. Mixtures containing different proportions of I and II were prepared which also contained lithium fluoride (III) as an internal standard. Results. A linear relationship was obtained when the intensity ratio (intensity of the 4.37 Å line of II/intensity of the 2.01 Å line of III) was plotted as a function of the weight fraction of II in the mixture. Similar results were obtained in the case of I. Using these standard curves, the weight fractions of I and II in 'unknown' mixtures were determined. The experimentally determined analyte concentration ranged between 98 and 104% of the true value. The relative error in the analyses of individual samples was < 10%. The minimum detectable weight fraction of I in II and II in I were 0.032 (3.2% w/w) and 0.034 (3.4% w/w), respectively. The minimum quantifiable weight fractions were 0.136 for I and 0.112 for II. Since the X-ray diffraction patterns of S(+)-ibuprofen and R(−)-ibuprofen are identical, the conclusions drawn regarding mixtures of I and II will also hold true in the quantitative analyses of mixtures of I and R(−)-ibuprofen. Plenum Publishing Corporation, 1997 S(+)-ibuprofen nationallicence R(−)-ibuprofen nationallicence (±)-ibuprofen nationallicence X-ray powder diffractometry nationallicence Phadnis Neelima College of Pharmacy, 308 Harvard Street S.E., University of Minnesota, 55455, Minneapolis, Minnesota aut Suryanarayanan Raj College of Pharmacy, 308 Harvard Street S.E., University of Minnesota, 55455, Minneapolis, Minnesota aut Pharmaceutical Research Kluwer Academic Publishers-Plenum Publishers 14/9(1997-09-01), 1176-1180 0724-8741 14:9<1176 1997 14 11095 https://doi.org/10.1023/A:1012198605891 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1012198605891 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Phadnis Neelima College of Pharmacy, 308 Harvard Street S.E., University of Minnesota, 55455, Minneapolis, Minnesota aut NATIONALLICENCE 700 1- Suryanarayanan Raj College of Pharmacy, 308 Harvard Street S.E., University of Minnesota, 55455, Minneapolis, Minnesota aut NATIONALLICENCE 773 0- Pharmaceutical Research Kluwer Academic Publishers-Plenum Publishers 14/9(1997-09-01), 1176-1180 0724-8741 14:9<1176 1997 14 11095 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer