Institute of Bioengineering and Nanotechnology

Guolin Xu, Daniel Lee, James T. M. Hsieh, Chunyan Zhang, Bruce Yu, Emril Mohamed Ali, Hong Xie, Zhiqiang Gao and Jackie Y. Ying

This research aims to study and develop a fully integrated, automated, high sensitivity, low-cost molecular diagnostic that can be used in clinics and for point-of-care applications. We have designed a microfluidic system that can rapidly dissociate tumor tissue, isolate and lyse target cells, extract and purify mRNA, amplify genes, and detect the amplified genes. This biochip device provides for the possibility of early cancer diagnosis using solid tumor tissue samples.

Mo Chao Huang, Wai Chye Cheong, Jiashen Wei, Jackie Y. Ying and Mo-Huang Li

Synthetic genes with intact, biological functions can be used for a variety of purposes such as protein overexpression in heterologous systems, engineering proteins with specific functions, and gene vaccine. The objective of this project is to develop an integrated microsystem to perform parallel and automatic gene assembly with fast turnaround at reduced cost to create synthetic genes. Short synthetic oligonucleotides will be assembled into a DNA sequence of suitable size for encoding genes and genomes based on polymerase chain reaction (PCR) or ligase chain reaction (LCR) assembly methods. Components required for performing gene assembly will be developed, miniaturized and integrated into a chip to transform gene assembly into an inexpensive, rapid process for commercial applications.

Jaehong Lim, Jessica Shan Oon, Joo-Eun Jee and Su Seong Lee

The overall research goal lies in developing high-throughput screening tools for membrane cancer biomarkers, capitalizing on our novel peptide libraries as an arsenal of capture agents. One-bead-one-compound peptide libraries are screened for binding to intact cancer cells, while novel technologies are developed for the validation of the capture agents that interact with the targets on the membrane with high fidelity. These capture agents can be used for immunohistochemistry of tumor tissues. The new technologies can also be applied to screen other types of intact cells

Jaehong Lim, Yi Li Ang, Jessica Shan Oon, Joo-Eun Jee and Su Seong Lee

This research effort aims to develop high-affinity and high-specificity capture agents for serum cancer biomarkers. With our novel technologies, protein capture agents can be developed by screening bead-based peptide libraries in a high-throughput platform. The entire process may take merely a week. Compared with antibodies, these synthetic peptides are attractive as protein capture agents for a variety of applications such as in vitro diagnostic devices, due to their low cost and high stability.

Ciprian Iliescu, Guolin Xu and Hanry Yu

Gene extraction using conventional immuno-magnetic beads requires a large sample size and a large number of beads. It cannot be used to isolate target genes when the sample is too small. This research uses dielectrophoresis to bind target cells and beads, so that fewer beads are required to capture the target. This greatly improves the target gene extraction efficiency and reliability. IBN's device consists of a sandwich of silicon electrodes and microchannels. Electroporation and in situ PCR techniques are applied on the bead-binded cells for cell lysis and amplification of the target genes. The biochip is targeted at applications involving very small samples (< 10 ml) for molecular diagnostics, such as those for the early detection of cancer, and the identification of rare bacteria and virus.

Kwong Joo Leck, Xinlei Qian, Shuguang Zhang and Charlotte Hauser

G-protein coupled receptors (GPCRs) belong to one of the most important protein classes responsible for signaling. GPCRs are able to signal through several G-protein pathways and through G-protein-independent pathways mostly in a ligand-specific manner. They are directly involved in a variety of physiological processes such as sensing, learning and memory, but they are also coupled to body functions such as cardiac, urinary, gastrointestinal and endocrine functions. Therefore, GPCRs are one of the most attractive classes of receptors for drug design and are direct targets of more than 50% of clinically prescribed medicine. Our laboratory is focused on the study of human serotonin receptors, water-based smell receptors from zebrafish, and Wnt receptors, FZDs (frizzled). The goal of our studies is to develop ultrasensitive devices for very early non-invasive medical diagnosis, as well as for drug targeting. Detailed structural knowledge of the GPCRs is needed to design these ultrasensitive devices. In addition, we are interested in the design and use of novel biological materials based on a new class of very short self-assembling peptides, which have potential applications in drug and gene delivery, as well as regenerative medicine.

Xiaojun Chen, Yanbing Zhu, Hua Wang, Somenath Roy, Jun Hui Soh and Jackie Y. Ying

This project aims to develop biosensors for specific biomarkers. The biosensors are based on the assembly/immobilization of biological sensing molecules onto the electrode surface, and the detection of the bound biomarkers using electrochemical techniques. The sensing molecules of the biosensors are designed to meet three requirements: (i) selective binding for specific biomarkers, (ii) stable attachment to conducting surface (electrodes), and (iii) self-assembly as and immobilization on densely packed monolayer/multilayers. High specificity will be attained using bioaffinitive interactions, while high sensitivity will be achieved by combining the bioaffinitive events with a signal amplifier such as enzyme and nanoparticulate catalyst. The biosensors are integrated with microfluidic systems as compact and portable devices for point-of-care applications.