Thermosensitive Polymers for Controlled Delivery of Hormones

Abstract

Thermosensitive polymeric systems, which remain as solution at room temperature and transform into gel at body temperature, have been extensively investigated for biomedical and pharmaceutical applications. The gel depot formed at the site of injection after the administration of an aqueous polymeric solution provides several benefits over the conventional delivery systems. These thermosensitive drug delivery systems are easy to formulate by simple mixing of therapeutic agents with the aqueous polymeric solutions, easy to administer by single injection, remain stable at the physiological conditions for a definite period of time, provide excellent stability for labile biomolecules such as proteins and peptides, and maintain the controlled and sustained release profile of the incorporated agents. Most of these systems are biodegradable and biocompatible, thereby eliminating the need of surgical explantation. This chapter discusses the classification of temperature sensitive systems, their synthesis and characterization procedures and provides a survey of recent literature on the in vitro and in vivo applications of thermosensitive polymers for controlled delivery of hormones.