Research areas

Explore our various research
interests and applications.

Vascular Repair with a Combination of Nanotopography and Stem Cells

Cardiovascular disease is the number one cause of death and disability in developed countries. Tissue engineering and regenerative medicine, which aim to repair and / or regenerate damaged tissue by mimicking the natural functional microenvironment, will be a promising solution to the problem. As the underlying cause of most cardiovascular diseases is related to atherosclerosis, we aim to address the root of the problem by

  1. Engineering vascular grafts for vascular replacement and
  2. Vascular repair using stem cells.

Fucoidan functionalization on poly(vinyl alcohol) hydrogels for improved endothelialization and hemocompatibility 


In the global aging population, vascular disease is the leading cause of death and disability in the aging population.  However, small diameter (<6mm diameter) synthetic vascular grafts lack good long-term patency (the ability to remain open).  Attempts to improve endothelialisation and vascular graft patency have focused on various physical, chemical and biofunctionalization techniques.Fucoidan modification significantly improved endothelial cell adhesion on PVA. 



Layered Reconstruction of Cornea

Cornea is a highly organized tissue with distinct structure in each of the corneal epithelial, stromal and endothelial layers. Nano-structures play an important role in the functional and structural support of these layers.

We hypothesize that nano-structured substrate can enhance cell-substratum interaction and provide optimal support for a cornea substitute.


Corneal regeneration and in vitro model of corneal endothelial dysfunction


Cornea endothelium dysfunction is one of the main reasons for corneal transplantation. Tissue engineered cornea endothelium will be highly sought after due to the shortage of donor cornea grafts. Our studies show that nanotopography enhances primary human cornea endothelial cell’s responses.  We have developed a patterned, biodegradable and implantable carrier membrane for corneal endothelial cells.  Together with clinical collaborators in Singapore Eye Research Institute, our team has developed an in vitro model of extracellular guttata topography in Fuchs’ Endothelial Dystrophy using microfabrication to study how the guttata impacted cell migration and cell therapy. The study has resulted in changes in surgical procedure to remove guttata structure on the cornea endothelium before cell therapy, improving the functional improvement of the cell therapy for Fuchs’ Endothelial Dystrophy patients. 


Primary human corneal endothelial cells were able to regenerate an endothelial monolayer on synthetic guttata structures with lower height or in dome shape. (Rizwan et al.)


Effect of sterilization on hydrogels


Understanding the effects of sterilization on GelMA and PVA hydrogels for translational tissue engineering applications. How do nano-scale surface features change cell behaviour and cell fate? How can we control the fate of a cell with topographical cues? We aim to obtain an understanding of the underlying mechanisms of topography-induced cell behaviour by studying changes in focal adhesion formation and the synergistic effects of nanotopography, biochemicals, and substrate stiffness in directing stem cell differentiation.


Effect of sterilization on GelMA hydrogels


Stem Cell and Nanotopography Interactions


Nanotopography showed significant influence on human mesenchymal stem cell (hMSC) and human pluripotent stem cell behavior. Our studies showed that hMSC aligned and elongated along the axis of the gratings. Expression of neuronal markers and upregulation of neuronal gene marker were detected. We have also shown that the influence of nanotopography on proliferation and differentiation is more significant compared to micro-topography. Nanotopographical cues can be incorporated into neural tissue engineering scaffold design, serving both as a differentiation cue and conduct guidance for axon regeneration.

Applications of Nanotopography in Neuronal Regeneration


Description: Comparison of the maturation of induced pluripotent -derived human neural progenitor cells from a patient with Rett Syndrome (RTT) and an isogenic control (CTRL) after 21 days of growth on a graphene scaffold. The cells were either electrically stimulated with 2 mA (eRTT and eCTRL) or not stimulated (RTT and CTRL).  The images were captured using confocal immunofluorescence with the markers Beta-Tubulin III (TUJ1), Microtubule-associated protein 2 (MAP2), and 4′,6-diamidino-2-phenylindole (DAPI). TUJ1 indicates the percentage of cells that committed to the neuronal lineage. MAP2 indicates the percentage of mature neurons. DAPI is used to identify cells. Image analysis showed that electrical stimulation helped to improve the maturation rate of both CTRL and RTT cells


Contact guidance has been shown to play a major role in many neural processes. Thus, there is interest in developing technologies that mimic the biophysics of the native neural extracellular matrix to help enhance neuronal processes on synthetic platforms. Of interest is neuronal differentiation, which has many important applications including the development of cell-based therapies for the treatment of neurological diseases, neuronal regeneration, fundamental neurological studies, and drug-screening, disease modelling and precision medicine platforms. Our lab has shown that biophysical cues such as stiffness, topography and electrical stimulation can be incorporate into scaffolds and used a neuronal differentiation cues for pluripotent stem cells (PSC), neural stem cells (NSC), and mesenchymal stem cells. On these platforms’ upregulation of neuronal genes and markers occurred, and cells changed to a neuronal morphology. The platforms have also been shown to promote contact guidance for axon regeneration.