Solvent free amorphisation for pediatric formulations (minitablets) using mesoporous silica
Research output: Contribution to journal › Conference abstract in journal › Research › peer-review
Introduction: Most silica based amorphisation strategies are using organic solvent loading methods. Towards pediatric formulations this is creating concerns. With this in mind the development of a dry amorphisation strategy was the focus of this study. The high internal surface area of mesoporous silica gel is densely crowded with silanol groups, which can provide hydrogen-bonding possibilities with a drug, potentially resulting in amorphisation. Purpose: Amorphous drugs provide an advantage in solubility; however, their low physical stability always remained concern. Additional there was a need to understand the mechanism and variables of dry amorphisation. Method: Ibuprofen (IBU) and Syloid® silica at different ratios were co-milled at variable milling times between 1 and 90 min. The interaction with; and amorphisation of IBU; on Syloid® silica was analyzed using SEM, FTIR, DSC and XRD. The co-milled powder was compressed into minitablets using moisture activated dry granulation (MADG). Drug release studies were conducted. Results: Ball milling as dry loading technique resulted within 30 min; in the conversion of crystalline IBU into an amorphous form in the presence of Syloid® silica. It was found that the amorphisation is a result of milling equilibrium, electrostatic interaction and hydrogen bonding between silanol groups of Syloid® silica and IBU. The extent of amorphisation was influenced by milling time, milling frequency and quantity of mesoporous silica. As a consequence, the amorphous IBU-silica samples showed improved solubility over the unmilled drug and showed physical stability of the amorphous IBU. Milling IBU alone did not result in an amorphous product; hence its dissolution did not show any improvement over unmilled drug. Conclusion: Dry amorphisation of silica based amorphous drug formulations does not involve organic solvents and is thereby acceptable for pediatric formulations, cost effective and time saving while increasing oral bioavailability of crystalline & poorly water soluble drugs.
|Journal||International Journal of Pharmaceutics|
|Publication status||Published - 25 Sep 2016|