What sets this approach apart is its precise, reversible phase transition combined with full biodegradability and functional modularity. Unlike conventional hydrogels or repeated invasive injections, it self-assembles at physiological temperature to retain high local drug concentrations, reducing dosing frequency and systemic exposure. The ability to fine-tune block composition, pendant group chemistry and loading modality offers unparalleled control over release kinetics and mechanical properties, enabling tailored solutions for ocular therapies, nerve regeneration and other advanced tissue-engineering applications.
Description
This biodegradable reverse thermal gel is built from triblock copolymers in a B–A–B architecture, where hydrophilic B-blocks such as polyethylene glycol, hyaluronan or poly(vinyl alcohol) flank a central polyurethane or polyester-urethane A-block bearing pendant functional groups or complexed actives. Below its transition temperature (25–40 °C) the material remains a free-flowing liquid suitable for syringe, cannula or catheter delivery; at body temperature (35–40 °C) it rapidly forms a hydrogel in situ. Active agents—ranging from small-molecule drugs and peptides to proteins and live cells—can be covalently tethered, ionically bound or simply admixed, then released gradually as the polymer backbone degrades. With molecular weights tunable from roughly 3,000 to 50,000 Da and a straightforward synthesis involving diol-diisocyanate coupling followed by PEGylation, this system serves both as a sustained-release depot for antibiotics, anti-inflammatories or ocular biologics and as a three-dimensional scaffold for tissue repair and cell growth.
Applications
Ocular sustained drug release
Injectable antibiotic drug depot
Nerve regeneration hydrogel scaffold
Tissue engineering cell scaffold
Minimally invasive anti-inflammatory delivery
Advantages
Minimally invasive delivery as a liquid that gels in situ at body temperature for precise placement
Sustained, controlled release of small molecules, proteins or cells through biodegradable polymer degradation
Versatile drug loading via covalent binding, ionic complexation or simple admixture to accommodate diverse therapeutics
Enhanced ocular bioavailability and reduced dosing frequency for treatments like intravitreal injections
Thermo‐responsive phase transition (25–40 °C) enables easy handling and targeted gel formation
Biocompatible and biodegradable composition eliminates need for surgical removal
Supports cell growth and tissue engineering, including nerve regeneration and wound healing scaffolds
IP Status
https://patents.google.com/patent/US9358301B2
