Recent Advances in Thermosensitive Hydrogels as Drug Delivery Systems: A Review

Polymers that exhibit physicochemical responses to stimuli have been widely explored as potential drug delivery systems. Different kind of stimuli investigated to date includes, for example, chemical substances and changes in temperature, pH and electric fields. Polymers that exhibit dramatic changes in their behavior in an aqueous solution at temperatures close to the body temperature are of particular interest in drug delivery and biomedical applications. Thermosensitive polymers have a wide range of applications, specially, the thermosensitive triblock copolymers because they exhibit unique aqueous solution properties, biodegradability and biocompatibility. These copolymers can be designed to be used as potential drug delivery systems for therapeutic protein drugs or poorly water soluble drugs. This article reviews the applications of polymer solutions with the ability to form in situ implants under temperature changes, in areas of interest to biomedical, pharmacist and engineer scientists. Recent advantages on thermosensitive and biodegradable polymers are discussed to give a wide overview of the available strategies to modify them in order to make them suitable for potential applications in health products.