Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-27T18:20:56.906Z Has data issue: false hasContentIssue false

Quantitation of crystallinity in substantially amorphous pharmaceuticals and study of crystallization kinetics by X-ray powder diffractometry

Published online by Cambridge University Press:  10 January 2013

Rahul Surana
Affiliation:
College of Pharmacy, 308 Harvard Street SE, University of Minnesota, Minneapolis, Minnesota 55455
Raj Suryanarayanan*
Affiliation:
College of Pharmacy, 308 Harvard Street SE, University of Minnesota, Minneapolis, Minnesota 55455
*
a)Corresponding author. Telephone: 612 624 9626; Fax: 612 626 2125; E-mail: [email protected]

Abstract

The first object was to develop an X-ray diffractometric method for the detection and quantification of crystalline sucrose when it occurs as a mixture with amorphous sucrose. Standards consisting of amorphous sucrose physically mixed with 1 to 5 weight percent crystalline sucrose were prepared. The sum of the background subtracted integrated intensities of the 12.7°2θ (6.94 Å) and 13.1°2θ (6.73 Å) sucrose diffraction peaks were linearly related to the weight percent crystalline sucrose. The limits of detection and quantitation of crystalline sucrose were 0.9% and 1.8% w/w, respectively. The second object was to study the kinetics of crystallization of sucrose as a function of temperature (at 102, 105 and 110 °C under a water vapor pressure of 0 Torr) and water vapor pressure (17.4, 19.8 and 21.4 Torr at 27 °C). In all cases, the crystallization kinetics was best described by the Avrami-Erofe’ev model (three-dimensional nucleation).

Type
Technical Articles
Copyright
Copyright © Cambridge University Press 2000

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Han, J., and Suryanarayanan, R. (1999). “A method for the rapid evaluation of the physical stability of pharmaceutical hydrates,” Thermochim. Acta 329, 163170.CrossRefGoogle Scholar
Hancock, B. C., and Dalton, C. R. (1999). “The effect of temperature on water vapor sorption by some amorphous pharmaceutical sugars,” Pharm. Dev. Tech. 4, 125131.CrossRefGoogle ScholarPubMed
Hancock, J. D., and Sharp, J. H. (1972). “Method of comparing solid-state kinetic data and its application to the decomposition of kaolinite, brucite and BaCO 3,J. Am. Ceram. Soc. 55, 7477.CrossRefGoogle Scholar
Hermans, P. H., and Weidinger, A. (1948). “Quantitative X-ray investigations on the crystallinity of cellulose fibers. A background analysis,” J. Appl. Phys. 19, 491506.Google Scholar
Klug, H. P., and Alexander, L. E. (1974). X-ray Diffraction Procedures for Polycrystalline and Amorphous Materials (Wiley, New York), 2nd ed., pp. 560–561.Google Scholar
Makower, B.and Dye, W. B. (1956). “Equilibrium moisture content and crystallization of amorphous sucrose and glucose,” J. Agric. Food Chem. 4, 7277.Google Scholar
PDF-2 (1996). International Centre for Diffraction Data, Newtown Square, PA, pattern number 24-1977.Google Scholar
Pikal, M. J., Lukes, A. L., Lang, J. E., and Gaines, K. (1978). “Quantitative crystallinity determinations for β-lactam antibiotics by solution calorimetry: Correlations with stability,” J. Pharm. Sci. 67, 767773.Google Scholar
Saleki-Gerhardt, A., Ahlneck, C., and Zografi, G. (1994). “Assessment of disorder in crystalline solids,” Int. J. Pharm. 101, 237247.Google Scholar
Sebhatu, T., Angberg, M., and Ahlneck, C. (1994). “Assessment of the degree of disorder in crystalline solids by isothermal microcalorimetry,” Int. J. Pharm. 104, 135144.CrossRefGoogle Scholar
Skoog, D. A., and Leary, J. J. (1992). Principles of Instrumental Analysis (Harcourt Brace College, Fort Worth, Texas), pp. 7–8.Google Scholar
Suryanarayanan, R. (1995). “X-ray powder diffractometry,” in Physical Characterization of Pharmaceutical Solids, edited by H. G. Brittain (Marcel Dekker, New York), pp. 187–221.Google Scholar
Taylor, L. S., and Zografi, G. (1998). “The quantitative analysis of crystallinity using FT-Raman spectroscopy,” Pharm. Res. 15, 755761.Google Scholar