Bioengineering Seminar Series

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"Smart Photonic Biomaterials for Diagnostic and Therapeutic Applications"

Sei Kwang Hahn, Ph.D.
Biomedical Nanomaterials Lab
Department of Materials Science and Engineering
Department of Chemical Engineering
Stanford University

Advances in photonics have stimulated significant progress in medicine with many techniques now in routine clinical use. However, the finite depth of light penetration in tissue is a serious constraint to clinical applications. Here, we developed implantable light-delivery devices using biodegradable polymers. With this light delivery system, we demonstrated photochemical tissue bonding (PTB) for wound healing with a Rose Bengal (RB) dye, achieving a full thickness (410 mm) wound closure of porcine skin. In addition, we successfully demonstrated the facilitated PTB using hyaluronic acid (HA) – RB conjugate and upconversion nanoparticle (UCNP). The UCNP emitting red and green light in the skin tissue by skin-penetrating near infrared (NIR) laser illumination could activate the RB dye and crosslink the collagen, inducing skin repair and deep tissue wound healing. Furthermore, we developed cell-integrated poly(ethylene glycol) hydrogels for in vivo optogenetic sensing and therapy. Real-time optical readout of encapsulated heat-shock-protein-coupled fluorescent reporter cells made it possible to measure the nanotoxicity of cadmium-based quantum dots in vivo. Using optogenetic cells producing glucagon-like peptide-1, we performed light-controlled therapy and obtained improved glucose homeostasis in diabetic model mice. Finally, we developed a smart contact lens composed of biosensors, drug delivery systems, and power sources for the treatment of diabetic retinopathy as a model disease. This presentation will provide the current state-of-the-art smart photomedicines for further clinical applications.

Sei Kwang Hahn obtained his B.S., M.S., and Ph.D. in the Department of Chemical and Biomolecular Engineering at Korea Advanced Institute of Science and Technology (KAIST). As the youngest Ph.D. at LG Chemical Group in 1996, he started his research on biodegradable polymer and then sustained release formulation of hGH, which was successfully commercialized in Korea under the trade name of Declage® in 2007. From 2001, he did his post-doctoral research with Prof. Allan Hoffman in the Department of Bioengineering at the University of Washington. After that, he worked for long acting formulation of various biopharmaceuticals at the Roche Group, Chugai Pharmaceutical Co. in Japan for more than three years. Since 2005, he has worked as a professor in the Department of Materials Science and Engineering at POSTECH, and an adjunct professor in the School of Interdisciplinary Bioscience and Bioengineering and in the Department of Creative IT Engineering at POSTECH. He was a consultant for Johnson & Johnson in New Jersey in 2008 and made a collaboration project contract with Hoffman-La Roche. In 2012, he joined in the Wellman Center for Photomedicine, Harvard Medical School and Massachusetts General Hospital for his sabbatical research supported by LG Yeonam Fellowship. Currently, he is a visiting professor at Stanford University starting from Feb 1, 2019. He was the Samsung Future Technology Committee Member for 2016-2018 and the Presidential Advisory Council on Science and Technology for 2017-2019. He is the founder and CEO of PHI BIOMED Co. He received the Controlled Release Society Award in 2018, the Minister of Health and Welfare Award in 2017, the Korean President Award in 2015 and Korean Minister of Education Award in 2013. He published more than 120 SCI journal papers including Nature Photonics, Nature Communications, Progress in Polymer Science, Advanced Materials, and ACS Nano, and filed more than 130 Korean and international patents. He is one of the editorial board members of ACS Biomaterials Science and Engineering, ACS Applied Bio Materials, Biomacromolecules, and an Associate Editor of Biomaterials Research.

The Bioengineering Seminar Series is co-hosted by the Parker H. Petit Institute for Bioengineering and Bioscience, and the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University.


  • Workflow Status:Published
  • Created By:Colly Mitchell
  • Created:05/28/2019
  • Modified By:Colly Mitchell
  • Modified:07/01/2019