A quick method for the quantitative analysis of mixtures. 1. Powder X-ray diffraction

Dong, W., Gilmore, C., Barr, G., Dallman, C., Feeder, N. and Terry, S. (2008) A quick method for the quantitative analysis of mixtures. 1. Powder X-ray diffraction. Journal of Pharmaceutical Sciences, 97(6), pp. 2260-2276. (doi: 10.1002/jps.21142)

Full text not currently available from Enlighten.

Abstract

described. It uses a simple algorithm based on linear regression in which the pure component phases are fitted to the mixture pattern using linear least squares. Unlike many methods that use only the peaks in the powder pattern, this technique uses all the measured data points in the 20 scan with minimal data processing. In practice, using 33 different samples on three diffractometers, the method can be shown to work well for mixtures with up to three components, giving mean errors between 1.7% and 3.9% for two-phase mixtures, and 4.0% and 8.6% for three-phase mixtures. These results compare favorably to those given by traditional Rietveld refinement. It is also shown that the Bruker GADDS system, which is designed for high throughput crystallization experiments, is capable of giving results of comparable accuracy to those derived from traditional, single sample diffractometers. It is possible to identify those mixtures for which one or more pure phase X-ray powder patterns are not available with a detection limit around 10%. The techniques are implemented in the PolySNAP computer program. The method requires very little computer time or user interaction. .

Item Type:Articles
Keywords:COMPONENTS COMPUTER-PROGRAM CRYSTALLIZATION CRYSTALLOGRAPHY COMMISSION DIFFRACTION high throughput crystallization high-throughput INTERNATIONAL UNION OUTCOMES PHASE PHASE-ANALYSIS POWDER DIFFRACTION quantitative analysis REFINEMENT RIETVELD METHOD ROUND-ROBIN SAMPLES SINGLE SQUARE SYSTEM X-RAY X-ray diffraction X-RAY-DIFFRACTION
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:Barr, Dr Gordon and Gilmore, Professor Chris
Authors: Dong, W., Gilmore, C., Barr, G., Dallman, C., Feeder, N., and Terry, S.
College/School:College of Science and Engineering > School of Chemistry
Journal Name:Journal of Pharmaceutical Sciences
ISSN:0022-3549

University Staff: Request a correction | Enlighten Editors: Update this record