Polyphenol-Inspired Molecular Design of Functional Polymers

Polyphenols are naturally occurring plant-derived chemicals. Natural polyphenols are thought to play important roles in the protection of plants from microbial infections and UV irradiation. We synthesize polyphenol-inspired polymers with narrow molecular weight distributions, and evaluate their antioxidant and antimicrobial properties.
[1] ACS Sustainable Chem. Eng., 2016, 4, 3857–3863.
[2] ACS Biomater. Sci. Eng., 2019, 5, 5578–5596.
[3] Polym. Chem., 2020, 11, 249–253.


Tunicate-Inspired Composites and Adhesives

Tunicate is a marine invertebrate having a stiff yet flexible outer covering called tunic. The tunic is a cellulose fiber reinforced protein composite that contains a post‐translationally modified amino acid, 3,4,5‐trihydroxyphenylalanine (TOPA) with a gallol functionality. We are trying to mimic the toughening strategy of tunicate by adopting the unique gallol-based interfacial adhesion design.
Putting a Band-Aid on wet skin is a challenging task because a thin water layer prevents the adhesion. Some marine creatures can produce biological molecules which are remarkably sticky even to wet surfaces. One of these creatures, tunicate, inspired us to synthesize novel underwater adhesives, which we aim to apply for tissue repair, wound dressing and biomedical devices.
[1] Biomacromolecules, 2017, 18, 2959–2966.
[2] J. Photopolym. Sci. Technol., 2020, 33, 123–127.
[3] J. Mater. Chem. B, 2020, 8, 6798–6801.


Bioinspired Self-Healing Polymers in Wet Environments

Polymers are widely used in marine environments due to their lightweight nature, good processability, and unique thermal/mechanical properties. Crack formation and other types of damage in polymeric materials used in wet environments could eventually lead to wholescale failure and/or the spread of microplastic pieces into marine environments. Imparting self-healing capabilities to those polymers would be a beneficial strategy for extending the life time and reducing the maintenance cost. We are designing and synthesizing self-healing polymers that can self-heal in seawater through dynamic bondings such as hydrogen bondings and coordination interactions. A judicious design principle at multiple length scales is needed, as most of the existing self-healing polymers suffer from swelling-induced mechanical instability and loss of self-healing ability because of a severe water uptake in fully submerged conditions.
[1] ACS Appl. Mater. Interfaces, 2016, 8, 19047–19053.
[2] RSC Adv., 2017, 7, 19288–19295.
[3] J. Mater. Chem. A, 2018, 6, 19643–19652.


Nanoparticle Engineering for Therapeutic and Diagnostic Applications

Targeted drug delivery enables site-specific drug release and thus reduce toxic side effects. Bioderived nanoparticles-based liquid biopsy detects signatures of diseases at early stages. In this project, interaction between nanoparticles and biointerfaces is investigated using biological particles (e.g., viruses and extracellular vesicles) and artificial particles (e.g., polymer capsules and polyphenol particles) as model systems.
[1] Small, 2015, 11, 2032–2036.
[2] Adv. Healthcare Mater., 2015, 4, 1796–1801.
[3] Adv. Science, 2019, 1801688.
[4] Chem. Mater., 2019, 31, 2191–2201.


One-Step Assembly of Metal-Phenolic Network (MPN)

We've developed a rapid and simple coating method based on the one-step assembly of MPN.[1-3] This versatile coating platform is now widely used all over the world to engineer nanomaterials and biointerfaces.[4] We have demonstrated a variety of applications including cell coating, MRI imaging, PET imaging, catalysis and so forth.
Prof. Insung S. Choi and co-workers applied this method to the sporulation/germination-inspired cytoprotective coating.[5,6] Certain bacteria form a proteinacious coating over cell walls to protect themselves from harmful environments such as nutrient deprivation, UV irradiation, desiccation, extreme temperature changes, and toxic chemicals (Sporulation).In response to the ending of stressful environments, bacteria degrade the coating and resume proliferation (Germination). We are also working on the reversible coating method of biointerfaces mimicking this Sporulation/Germination processes for unique applications.
[1] Science, 2013, 341, 154–157.
[2] Chem. Mater., 2014, 26, 1645–1653.
[3] Angew. Chem. Int. Ed., 2014, 53, 5546–5551.
[4] Nano Today, 2017, 12, 136–148.
[5] Angew. Chem. Int. Ed., 2014, 53, 12420–12425.
[6] Nanoscale, 2015, 7, 18918–18922.


Back to top of this page