title: Influence of Polymers on the Crystal Growth Rate of Felodipine: Correlating Adsorbed Polymer Surface Coverage to Solution Crystal Growth Inhibition.
abstract: The bioavailability of orally administered drugs that exhibit poor aqueous solubility can be enhanced with the use of supersaturating dosage forms. Stabilization of these forms by preventing or inhibiting crystallization in solution is an important area of study. Polymers can be used to stabilize supersaturated systems; however, the properties that impact their effectiveness as crystal growth rate inhibitors are not yet fully understood. In this study, the impact of various polymers on the crystal growth rate of felodipine and the conformation of these polymers adsorbed to crystalline felodipine was investigated in order to gain a mechanistic understanding of crystal growth inhibition. It was determined that polymer hydrophobicity impacted polymer adsorption as well as adsorbed polymer conformation. Polymer conformation impacts its surface coverage, which was shown to directly correlate to the polymer's effectiveness as a growth rate inhibitor. By modeling this correlation, it is possible to predict polymer effectiveness given the surface coverage of the polymer.
authors.affiliation: School of Chemical Engineering, College of Engineering, and ‡Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University , West Lafayette, Indiana 47907, United States.
authors.forename: Caitlin J
authors.initials: CJ
authors.lastname: Schram
authors.affiliation: School of Chemical Engineering, College of Engineering, and ‡Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University , West Lafayette, Indiana 47907, United States.
authors.forename: Lynne S
authors.initials: LS
authors.lastname: Taylor
authors.affiliation: School of Chemical Engineering, College of Engineering, and ‡Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University , West Lafayette, Indiana 47907, United States.
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Beaudoin
mesh_terms: D000327:Adsorption; D015736:Felodipine; D057927:Hydrophobic and Hydrophilic Interactions; D015394:Molecular Structure; D010316:Particle Size; D011108:Polymers / Q000737:chemistry*; D012996:Solutions; D013499:Surface Properties
chemical_list: D011108:Polymers; D012996:Solutions; D015736:Felodipine