These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Physical characterization of meso-erythritol as a crystalline bulking agent for freeze-dried formulations.
    Author: Fujii K, Izutsu K, Kume M, Yoshino T, Yoshihashi Y, Sugano K, Terada K.
    Journal: Chem Pharm Bull (Tokyo); 2015; 63(5):311-7. PubMed ID: 25948324.
    Abstract:
    The purpose of this study was to identify and characterize new crystalline bulking agents applicable to freeze-dried pharmaceuticals. Thermal analysis of heat-melt sugar and sugar alcohol solids as well as their frozen aqueous solutions showed high crystallization propensity of meso-erythritol and D-mannitol. Experimental freeze-drying of the aqueous meso-erythritol solutions after their cooling by two different methods (shelf-ramp cooling and immersion of vials into liquid nitrogen) resulted in cylindrical crystalline solids that varied in appearance and microscopic structure. Powder X-ray diffraction and thermal analysis indicated different crystallization processes of meso-erythritol depending on the extent of cooling. Cooling of the frozen meso-erythritol solutions at temperatures lower than their Tg' (glass transition temperature of maximally freeze-concentrated phase, -59.7°C) induced a greater number of nuclei in the highly concentrated solute phase. Growth of multiple meso-erythritol anhydride crystals at around -40°C explains the powder-like fine surface texture of the solids dried after their immersion in liquid nitrogen. Contrarily, shelf-ramp cooling of the frozen solution down to -40°C induced an extensive growth of the solute crystal from a small number of nuclei, leading to scale-like patterns in the dried solids. An early transition of the freezing step into primary drying induced collapse of the non-crystalline region in the cakes. Appropriate process control should enable the use of meso-erythritol as an alternative crystalline bulking agent in freeze-dried formulations.
    [Abstract] [Full Text] [Related] [New Search]