Abstract
The dehydrated lactose forms αH and αS were investigated by time- and temperature-resolved X-ray powder diffractometry and differential scanning calorimetry. We found different X-ray structures for these two forms, which is probably related to the different dehydration processes. The rapidly dehydrated form αH obviously has the same X-ray structure as the starting material α-lactose monohydrate, although the crystallinity is reduced. A thermally induced transition of the αH-form into the αS-form was observed. This transition should allow one to “switch” between the physicochemical properties of the excipient, which may be important for applications in pharmaceutical and food industries.
Zusammenfassung
Die dehydratisierten Lactose-Formen αS und αH wurden durch zeit- und temperaturaufgelöste Röntgendiffraktometrie sowie durch Dynamische Wärmeleitfähigkeits-Differenz-Kalorimetrie (DSC) untersucht. Beide Formen besitzen unterschiedliche Röntgenstrukturen, die wahrscheinlich auf die unterschiedlichen Dehydratationsbedingungen zurückzuführen sind. Das schnell dehydratisierte Material αH zeigt die Röntgenstruktur des Ausgangsmaterials, α-lactose-Monohydrat, jedoch ist die Kristallinität gegenüber dem Ausgangsmaterial reduziert. Die fest-fest Umwandlung der αH-Form in die αS-Form läßt sich thermisch induzieren. Die Umwandlung ermöglicht ein “Umschalten” zwischen den unterschiedlichen physikalisch-chemischen Eigenschaften der Materialen und könnte für Anwendungen in der Pharmazeutischen Industrie und der Lebensmitteltechnik interessant sein.
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Figura, L.O., Epple, M. Anhydrous α-lactose A study with DSC and TXRD. Journal of Thermal Analysis 44, 45–53 (1995). https://doi.org/10.1007/BF02547132
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DOI: https://doi.org/10.1007/BF02547132