| Injectable, biodegradable thermoplastics represent a promising biomaterial class for localized peptide and protein delivery. In this delivery system a drug is incorporated within a polymer melt and then injected into a body site. epsilon-Caprolactone (CL) and trimethylene carbonate (TMC) were chosen as the principal constituting monomers and oligomers of various ratios were prepared using primary, secondary and tertiary alcohols as initiators. The thermal properties of the polymers were studied via a differential scanning calorimeter and their viscosities were measured using a parallel plate rheometer. In vitro degradation studies and in vitro release studies, using vitamin B12 (VB12) as a model drug and trehalose as an osmotic excipient, were carried out. Oligomer properties were observed to be dependent on the type of the initiator used and the ratio of its constituting monomers, resulting in a wide range of release rates. (Abstract shortened by UMI.)... |
