About

The Laboratory for Biosensing conducts inter-disciplinary research. We are to develop functional biomaterials with specific structures or catalytic activities by microbial engineering and protein engineering strategies. The other aims include exploiting integrated intelligent analytical methods and sensing devices for bioenergy process, environment, industrial control, medical care, clinical diagnostics and food safety. Specifically, our research covers the following fields:

1. Design, construction and functionalization of biomacromolecules, microbial surface display
　 Designing of protein with special properties is prerequisite for developing enzyme-based catalysts, studying molecule interactions and other applications. We express stable enzymes with high activity in vitro by conventional protein engineering, and construct whole-cell catalysts by cell surface display. Furthermore, phage and yeast display based screening systems are under development in our lab to study protein/peptide-target molecule interactions, to obtain functional ligands with high affinity and specificity for a wide variety of applications including search of antibody substitutes and imitation of antibody functions.
Fig.1 Scheme for design and construction of biomacromolecule. A), protein engineering. B), affinity peptide screening by phage display. (B. Liang et al., Analytical Chemistry 2012, 84, 275-282; H. Qi et al., Journal of Molecular Biology 2012, 417, 129-143)

2. Biochip (protein microarray and oligosaccharide microarray)
 ---In post-genomics era, both proteomics and functional glycomics have received increasing attention in biology and bio-medicine. By developing novel probes which have specific binding sites for proteins or carbohydrates, novel protein microarrays and oligosaccharide microarrays can be constructed and assay kits are developed. Especially, we develop microarrays to monitor the bioenergy process, for example, to mointor the bio-conversion of lignocellulose to fuel ethanol in real time.
Fig. 2 Scheme for nano-inspired protein microarray

3. Controllable self-assembly
---By using self-assembly approach, ordered bio-nanostructure is constructed to understand biological structure, function and biomimicking.
　　　
Fig.3 TEM images of negatively stained individual tetraArg–M13 phages A) and gold-nanoparticle self-assembled individual tetraArg–M13 phages B). (A. Liu, et al., Advanced Materials 2009, 21, 1001–1005.)

4. Biosensors based on novel bio-nanostructures
--- Novel biosensors and bioanalytical techniques are developed by exploring of the combination of functional nanomaterials and biomaterials.
Fig.4 Xylose electrochemical biosensor based on xylose-dehydrogenase-displayed E. coli and multi-walled-carbon-nanotubes modified electrode. A).Construction of modified electrode. B). Proposed electrocatalytic oxidation of xylose by XDH-bacteria. (L. Li, et al., Biosensors & Bioelectronics 2012, 33, 100-105.)

5. Stochastic protein nanopore sensing of single molecules
--- Stochastic single molecules detection and next-generation DNA sequencing techniques are developed based on the protein nanopore and solid-state nanopore.
　　　　　
Fig.5 Unzipping of double-stranded DNA in engineered α-hemolysin pores. (A. Liu, et al, J. Phys. Chem. Lett. 2011, 2, 1372-1376.)

6. Biofuel cells
--- By integrating bioelectrochemistry, nanoscience and surface modification, novel nano/micro structures are developed to immobilize electricigens for fast direct electron transfer. Another aim is to solve the key problems in the development of microbial fuel cells, for instance, we explore novel microbial electrolysis cells and get electric power benefiting from treatment of industrial and agricultural wastes. Meanwhile, strategies are established to improve the microbial conversion efficiency and output power density to develop portable, efficient and long-life microbial fuel cells.
Fig. 6 Scheme for microbial fuel cell