Fabrication of an Injectable Drug Delivery System for Biomedical Applications

The drug delivery system is an important subject in regenerative medicine. An effective system should facilitate controlled release and ensure prolonged drug delivery into the target site in contrast with injection. Utilizing hydrogel carriers to be injected into the target tissue is considered to be a proper strategy to achieve both reduction of injection frequency and sustained drug release. Micron-size particle hydrogels present an excellent choice, not only enhancing drug release but also, adjusting the physical and chemical properties of the hydrogel. The Fabrication of droplets will take place using microfluidic devices and polymerization through a chemical or physical reaction. In the current study, the thermosensitive polymer was chemically modified, resulting in the fabrication of non-uniform size and self-aggregation of spherical microgels which are key factors in the encapsulation process. In our approach, the fabrication of micron-sized spherical hydrogel constructs was performed by utilizing an appropriate parameter within a microfluidic device with a surface-modified thermosensitive polymer. Injectable microparticles with self-assembly properties in physiological temperature fabricated using conjugation of phenol moieties into polyvinyl alcohol (PVA-Ph) as the base core. Following this, the thermo-sensitive modified Pluronic (Plu)۱۲۷ with phenol moieties (Plu-Ph) was synthesized as a shell of the microparticle. The core-shell-based microparticle can form hydrogel within the physiological condition in the target site through interpenetrating of the Pluronic on the shell part of the microparticle. Based on the result, the core-shell microparticle was fabricated correctly. The fabrication of the construct was characterized using NMR and SEM, and its effect on the cell viability was evaluated via Live live-dead assay. The NMR result confirmed the PVA-Ph and Pluronic-Ph synthesis. The SEM micrograph and macroscopic image of the microparticle showed the spherical and relatively monodisperse in size of particles. Our present study provides a new drug delivery system based on PVA-Ph/Plu core-shell microparticles that could dope with drugs.