報告題目： Thermogels for Biomedical Applications
報告人：Xian Jun Loh 教授/院長
ID：319 539 079 會議密碼：468524
Thermogels are valuable soft materials for biomedical applications. At low temperatures, they remain as solutions which can be used to entrap therapeutic payloads such as drugs and proteins within their solvated polymer matrices. Upon injection into the body, higher body temperatures cause the solutions to gelate in situ at the site of injection, allowing localized placement for applications such as drug delivery. Herein, we present our three-component thermogelling polyurethane technology comprising of biocompatible polyethylene glycol (PEG), poly(propylene glycol) (PPG) and a third component, which can be poly(caprolactone) (PCL), poly(tetrahydrofuran) carbonate (PTHF) or poly[(R)-3-hydroxybutyrate-(R)-3-hydroxyhexanoate] (PHBHx), as a unique platform for biomedical applications. Our thermogels loaded with anticancer drugs were highly effective for inhibition of tumour growth in vivo using mice models. Docetaxel-loaded PEG-PPG-PHBHx thermogels showed enhanced anti-melanoma effects on solid melanoma tumours compared with the free drug, whilst exhibiting excellent biosafety and no apparent harm to organs. With doxorubicin-loaded PEG-PPG-PTHF thermogels, sustained drug release for 16 days in vivo successfully inhibited growth of hepatocellular carcinoma. Impressively, incorporating a dye capable of aggregation-induced emission into the polymer structure allowed it to be used to track in-vivo doxorubicin release status and gel degradation, revealing valuable insights on the drug transportation pathways. Recent efforts on PEG-PPG-PCL thermogels are concentrated on their unprecedented use in vitreoretinal surgery as a vitreous substitute and an internal tamponading agent. The thermogel showed long-term biocompatibility in rabbit vitrectomy models, and was an effective endotamponade in a non-human primate surgical retinal detachment model. This is likely attributed to the thermogel providing support for the retina and preventing subsequent re-detachments. Intriguingly, there is reformation of a vitreous-like body that mimics the property of natural vitreous as the polymer biodegrades over three months. Thermogels offer vast scope for customizable tuning of their mechanical properties for various biomedical applications.
Xian Jun Loh院長是一名生物材料跨學科領域的高分子化學家，是新加坡材料研究院院長、新加坡國家化學研究院副院長、英國皇家化學學會會士、全球高被引科學家。Xian Jun Loh院長的主要研究方向是應用於生物醫學和健康領域的超分子、刺激響應聚合物和水凝膠的研發，迄今為止在生物材料領域發表了200餘篇高水平學術論文、19項發明專利、45篇編著章節和6本學術專著。同時，Xian Jun Loh院長也是6家國際期刊編委會成員，多家重大基金組織資深顧問。