www.nanotoday-conference.com

A*STAR Outstanding Publications Award 2009, 2010, 2012, 2013 and 2014
A*STAR Patent Power Award 2009 and 2010
Singapore HEALTH Award (Platinum) 2012, (Gold) 2008 and 2010

ISO Certified (ISO 9001:2008)

OHSAS Certified (SS 506 Part 1:2009/ BS OHSAS 18001:2007

RESEARCH AREAS > Research Staff Details

Nanomedicine

   

YANG Yi Yan
Group Leader

Tel: 6824 7106
Email: yyyang@ibn.a-star.edu.sg

View CV

Adjunct Associate Professor, Department of Pharmacy, National University of Singapore, 2008-present
Visiting Scientist/Research Fellow/Senior Research Fellow, Institute of Materials Research & Engineering (Singapore), 1998-2003
Assistant/Associate Professor, 1990-1998

Ph.D. in Chemical Engineering, Tsinghua University (China), 1990
B.E. in Chemical Engineering, Hefei University of Technology (China), 1985

Projects Publications Patents

Nanomedicine

1. Biodegradable Cationic Core-Shell Nanoparticles for Co-Delivery of Drugs and Genes

Ashlynn Lee, Zhan Yuin Ong, Wei Cheng, Pei Yun Teo, Xiyu Ke, Chuan Yang, Majad Khan, Shujun Gao and Yi Yan Yang

This research focuses on the development of novel biodegradable cationic nanoparticles for the co-delivery of drugs and genes for improved cancer therapy. IBN researchers have recently designed and synthesized biodegradable polymers and modified PEI with a rapid and facile synthetic approach. These polymers self-assemble into nanoparticles in aqueous solutions after siRNA binding. siRNA is employed to down regulate proteins in cancer cells to sensitize the cells to immune cells and anticancer drugs. By enabling the co-delivery of drugs and genes/proteins in a single system, synergistic therapeutic effects have been achieved in suppressing cancer cell proliferation.

2. Polymeric Core-Shell Nanoparticles for Cancer Therapy

Shrinivas Venkataraman, Jeremy Tan, Chuan Yang, Amalina Bte Ebrahim Attia, Xiyu Ke, Sangeetha Krishnamurthy, Shujun Gao and Yi Yan Yang

This research aims to develop safe polymer-based carriers with nanometer particle size and narrow size distribution, high drug loading capacity and kinetic stability to transport small molecular anticancer drugs to tumor cells based on passive and active targeting. Biodegradable polycarbonate-based block copolymers with various functional groups have been synthesized through metal-free organocatalytic ring-opening polymerization using methoxy PEG as a macroinitiator. Two platform technologies have been developed to deliver drug molecules with different structures. For example, core-shell nanoparticles formed from acid- and urea-functionalized polycarbonates provide extremely high loading capacity for drugs having amine functional group (e.g. doxorubicin) due to non-covalent interactions such as ionic, hydrogen-bonding and hydrophobic interactions between the polycarbonates and drug molecules. In another platform technology, cholesterol-functionalized polycarbonate-based block copolymers offer high loading levels for hydrophobic drugs with a rigid structure (e.g. paclitaxel and cyclosporin) with excellent kinetic stability and sub-50 nm size. In a tumor-bearing mouse model, they were observed to accumulate in leaky tumor tissue after tail vein injection. In addition, the co-delivery of dual drugs that target both cancer stem cells and cancer cells has significantly improved anti-tumor efficacy both in vitro and in vivo. These polymers allow for further attachment of biological ligands for active tumor targeting.

3. Macromolecular Antimicrobials to Combat Microbes

Chuan Yang, Shaoqiong Liu, Jeremy Tan, Zhan Yuin Ong, Victor Ng, Noel Xu, Xin Ding, Willy Chin, David Voo, Siti Nurhanna Riduan, Yugen Zhang and Yi Yan Yang

Due to the increasing resistance of bacteria to conventional antibiotics, macromolecular antimicrobial peptides and polymers have received significant attention. Most conventional antibiotics do not physically damage the cell wall but penetrate into the target microorganism and act on specific targets, such as breakage of double-stranded DNA due to inhibition of DNA gyrase, blockage of cell division and triggering of the intrinsic autolysins. As a consequence, bacterial morphology is preserved and the bacteria can easily develop resistance. In contrast, our macromolecular antimicrobials do not have a specific target in microbes, and they interact with microbial membranes based on electrostatic interaction, thereby inducing damage to the microbial membranes by forming pores in the membranes. This physical action prevents microbes from developing resistance, and promotes lysis of multidrug-resistant microbes. In this project, we have designed and synthesized amphiphilic antimicrobial peptides and polymers, which form a secondary structure when in contact with the bacterial cell membrane to enhance interactions with lipid domains of the bacterial membrane, disrupting the membrane. The structure of the macromolecules is optimized in terms of hydrophobicity/hydrophilicity balance, molecular weight, counter ion and quaternization agent to achieve strong antimicrobial activities with no or minimal toxicity for applications in blood stream or skin infections, tuberculosis, surface sterilization and consumer products. The antimicrobial macromolecules are also formulated as antimicrobial and antifouling coatings for catheters, medical devices and implants to prevent infections associated with biofilms.

FEATURED PUBLICATIONS

Antimicrobial Hydrogels: A New Weapon in the Arsenal Against Multidrug-Resistant Infections
Advanced Drug Delivery Reviews, 78 (2014) 46-62.
(IF: 12.707) article

Role of Grafted Alkoxybenzylidene Ligand in Silica-Supported Hoveyda–Grubbs-Type Catalysts
Chemical Communications, (2014)
DOI: 10.1039/c4cc08627a.
(IF: 6.718) article

Benzyl Chloride-Functionalized Polycarbonates: A Versatile Platform for the Synthesis of Functional Biodegradable Polycarbonates
Macromolecules, (2014)
DOI: 10.1021/ma501734y.
(IF: 5.927) article

More   

JOIN US!

Research Positions

Corporate Administration Positions

Institute of Bioengineering and Nanotechnology   31 Biopolis Way, The Nanos, #04-01, Singapore 138669   Tel: +65 6824 7000   Fax: +65 6478 9080   Email: enquiry@ibn.a-star.edu.sg   |   View IBN Privacy Statement