Purpose: The stabilization mechanism of a supersaturated solution of mefenamic acid (MFA) from a solid dispersion with EUDRAGIT(®) EPO (EPO) was investigated.
Methods: The solid dispersions were prepared by cryogenic grinding method. Powder X-ray diffractometry, in vitro dissolution test, in vivo oral absorption study, infrared spectroscopy, and solid- and solution-state NMR spectroscopies were used to characterize the solid dispersions.
Results: Dissolution tests in acetate buffer (pH 5.5) revealed that solid dispersion showed > 200-fold higher concentration of MFA. Supersaturated solution was stable over 1 month and exhibited improved oral bioavailability of MFA in rats, with a 7.8-fold higher area under the plasma concentration-versus-time curve. Solid-state (1)H spin-lattice relaxation time (T(1)) measurement showed that MFA was almost monomolecularly dispersed in the EPO polymer matrix. Intermolecular interaction between MFA and EPO was indicated by solid-state infrared and (13)C-T(1) measurements. Solution-state (1)H-NMR measurement demonstrated that MFA existed in monomolecular state in supersaturated solution. (1)H-T(1) and difference nuclear Overhauser effect measurements indicated that cross relaxation occurred between MFA and EPO due to the small distance between them.
Conclusions: The formation and high stability of the supersaturated solution were attributable to the specifically formed intermolecular interactions between MFA and EPO.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1007/s11095-011-0655-7 | DOI Listing |
Pharm Dev Technol
January 2025
Department of Pharmaceutics, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Madhavnagar, Manipal - 576104, Karnataka, India.
Purpose: Supersaturated formulations have been widely explored for improving the oral bioavailability of drugs by using mesoporous silica (MS) to generate supersaturation via molecular adsorption; however, this is followed by precipitation. Several precipitation inhibitors (PI) have been explored to prevent precipitation and maintain the drug in solution for a longer period. However, the combined approach of MS and PIs, the impact of MS and Silica, and the loading of high-molecular-weight neutral molecules such as Cyclosporine A (CsA) have not yet been explored.
View Article and Find Full Text PDFNat Commun
January 2025
Department of Civil & Environmental Engineering, University of California Los Angeles (UCLA), Los Angeles, CA, USA.
Biomater Sci
January 2025
Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China.
: To explore the relationship between the stability of poly(gamma-glutamic acid) (γ-PGA) dispersion systems with γ-PGA of different molecular weights (MWs) and concentrations and type I collagen mineralization. : γ-PGA was used as a noncollagenous protein (NCP) analogue to regulate the stability of supersaturated γ-PGA-stabilized amorphous calcium phosphate (PGA-ACP) solutions by changing the γ-PGA MW (2, 10, 100, 200 and 500 kDa) and concentration (400, 500 and 600 μg mL). Then, the optical density (OD) at 72 h was measured to determine the PGA-ACP solution stability.
View Article and Find Full Text PDFInt J Biol Macromol
December 2024
State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China. Electronic address:
Protein crystallization is essential for determining the three-dimensional structures of biomacromolecules and advancing biopharmaceutical development, yet it remains a major challenge in structural biology due to common issues like slow nucleation rates and inconsistent crystal quality. Herein, a dual-drive crystallization (DDC) strategy, relying on a composite film of sodium alginate (SA) and hyaluronic acid (HA), is reported to synergistically regulate both protein adsorption and solution supersaturation. Driven by the electrostatic interactions of SA and the water absorption properties of HA, the SA/HA film achieves enhanced crystallization efficiency and controlled crystal quality mainly.
View Article and Find Full Text PDFJ Colloid Interface Sci
December 2024
Department of Chemical Sciences, SSPC, the Research Ireland Centre for Pharmaceuticals, Bernal Institute, University of Limerick, V94 T9PX, Ireland. Electronic address:
Hypothesis: It is hypothesised in this work that mesoscale clusters will be present in both undersaturated and supersaturated solutions of organic pharmaceutical molecules. These clusters, being loose aggregates, could be sensitive to shear forces experienced during filtration. Thus, comparing the behaviour of these clusters alongside nanoparticles during filtration-an important sample treatment parameter during crystallization-will elucidate qualitative differences from solid, crystalline nanoparticles of similar size.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!