Preparation, characterization, and pharmaceutical application of linear dextrins. II. Complexation and dispersion of drugs with amylodextrin by freeze-drying and kneading.
The ability of amylodextrin (a linear dextrin) to act as a complexing agent or as a carrier for solid dispersion was evaluated. Blends of amylodextrin with diazepam or prednisolone were freeze-dried and kneaded at elevated temperatures, respectively. The products were analyzed by DSC, X-ray diffractometry, and FTIR spectroscopy. Complex formation with amylodextrin by freeze-drying was found not to occur for diazepam but for prednisolone at a molar ratio of 1 to 1. The freeze-dried product of diazepam with amylodextrin proved to be a solid dispersion. Solid dispersions were formed by both wet (with ethanol) and dry kneading at elevated temperatures of low-melting drugs such as lidocain, diazepam, and methyl-PABA with amylodextrin. No solid dispersions were obtained for high-melting drugs such as prednisolone and salicylic acid. The results point to the formation of solid dispersions by a melting mechanism during the process of kneading at elevated temperatures of low-melting drugs with amylodextrin.
Te Wierik
G H
GH
Department of Pharmaceutical Technology and Biopharmacy, University of Groningen, The Netherlands.
Eissens
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Besemer
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Lerk
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D002152:Calorimetry, Differential Scanning; D003912:Dextrins / Q000737:chemistry*; D003975:Diazepam / Q000737:chemistry; D004337:Drug Carriers; D004339:Drug Compounding; D005583:Fourier Analysis; D005612:Freeze Drying; D011239:Prednisolone / Q000737:chemistry; D013055:Spectrophotometry, Infrared; D013696:Temperature; D014961:X-Ray Diffraction
D003912:Dextrins; D004337:Drug Carriers; C010026:amylodextrins; D011239:Prednisolone; D003975:Diazepam