The Effects of the Addition of Polymers in Amorphous Pharmaceuticals on Glass and Crystal Properties

Authors: Dustine Izzo, Sarah Wolf

SUNY Campus: SUNY Cortland

Presentation Type: Poster

Location: UU 108

Presentation #: 82

Timeslot: Session D 3:00-4:00 PM

Abstract: Amorphous solids are prevalent in the field of pharmaceuticals as they are often more bioavailable or better for dosing than their crystalline counterparts. Polymer additives are used for a variety of reasons in drugs. Previous studies show that when even very small amounts of polymer are added to amorphous pharmaceutical ingredients it can impact the molecular mobility and thermal properties of drugs. In the case of Indomethacin (IMC), polymer additives can selectively accelerate crystal growth of differing polymorphs. As a result, there is an interest in exploring the impact of molecular mobility and thermodynamics on this drug. To study these effects, mixtures of varying percents by mass of polyethylene oxide (PEO) or polyvinylpyrrolidone (PVP) in IMC by mass were made. Differential scanning calorimetry (DSC) was used to investigate properties including glass transition temperatures (Tg), liquid fragility (via cooling rate dependent Tg), and heat capacity steps in the Tg. From the glass transitions found in the cooling of the mixtures, fragility of the mixtures was calculated. It was found that PEO caused a much larger decrease in fragility, where as the PVP mixtures’ fragility remained relatively close to that of IMC. This work may be useful in the applications of polymer additives in pharmaceuticals. An understanding of the thermodynamics of crystal growth changes and other impacts of polymer additives can result in using polymers as effectively as possible.