Principal Investigator: Prof. Li Pei, Pauline

1) Development of nanocarriers for gene and drug deliveries

We have established a core-shell particle platform technology which allows us to design and synthesize highly uniform particles in nano- to micro-scaled sizes with different physical and chemical properties. One of the research areas in our group is to develop non-viral polyethyleneimine-based nanocarriers for gene and drug deliveries. Our PEI-based amphiphilic core-shell nanoparticles show great potential to be efficient nanocarriers for deliveries of plasmid DNA and drugs. We have also synthesized a gelatin/PEI core-shell nanogel as a new type of siRNA nanocarrier. Results show that the gelatin/PEI core-shell nanogel particles can effectively deliver the siRNA molecules to the site of function and knock-down the gene of interest.

Research Highlights in Biointerphases

Featured Article in Global Medical Discovery

Selected Publications:

1. Hetti Mimi, Kin Man Ho, Yuen Shan Siu, Aihua Wu and Pei Li*, “Polyethyleneimine-Based Core-Shell Nanogels: A Promising siRNA Carrier for Argininosuccinate Synthetase mRNA Knockdown in HeLa Cells”, Journal of Controlled Release, 158, 123-130 (2012)
2. Yuen Shan Siu, Lijun Li, Man Fai Leung, Kam Len Daniel Lee, and Pei Li*, “Polyethyleneimine-Based Amphiphilic Core-Shell Nanoparticles: Study of Gene Delivery and Intracellular Trafficking”, Biointerphases, 7, 16 (2012).
3. Pei Li*, Yuen Shan Siu, Kin Man Ho, Wei Li, “Amphiphilic Core-Shell Nanoparticles Containing Hairy Polyethyleneimine Shells as Effective Nanocarriers for Gene Delivery”, Book chapter in the “Selected Topics in Nanomedicine” published by World Scientific Publishing, (In press, 2012).
4. Min Feng, Pei Li*, “Amine-containing core-shell nanoparticles as potential drug carriers for intracellular delivery”, Journal of Biomedical Materials Research, 80, 184-193 (2007).
5. Junmin Zhu, Angie Tang, Lai Pang Law, Min Feng, Kin Man Ho, Daniel Kam Len Lee, Frank W. Harris, Pei Li*, “Amphiphilic Core-shell Nanoparticles with Poly(ethylenimine) Shells as Potential Gene Delivery Carriers”, Bioconjugate Chemistry, 16, 139-146 (2005).

2) Development of nanosorbents for bioseparation and purification

The technology provides a fast and simple solution for selective removal of endotoxin from protein solutions in physiological buffers. It adopts a type of magnetic core-shell (MCS) composite particles, which can selectively bind endotoxin in protein mixtures and are easily removed by a magnetic separation. The endotoxin level of the treated protein solution is low enough (< 10 EU/mL) to allow for further process, analyze or even administrate to mammals.

Our method has the following advantages:

• High selectivity for endotoxin adsorption in both basic and acidic protein mixtures (e.g. bovine serum albumin).
• Effective in broad working conditions (different pHs, electrolyte concentrations and buffer types).
• Simple process which does not require multiple extraction steps (unlike Triton X-114 extraction method).
• Low cost, avoiding the use of expensive reagent (e.g., polylysine).
• Fast purification process without common problems such as filter blocking in microfiltration and time-consuming process when using porous adsorbents.

Selected Publications:

1. Kin Man Ho, Pei Li*, “Selective endotoxin nanosorbents, and a method of removing endotoxin by using amphiphilic core-shell nanosoorbents”, U.S. Patent Application (Pending, 2011).
2. Kin Man Ho, Pei Li*, “Design and Synthesis of Novel Magnetic Core-Shell Polymeric Particles”, Langumir, 24, 1801-1807 (2008).