Nianqiang (Nick) Wu
My research aims to gain fundamental understanding of charge transfer and energy transfer in electrochemical and photoelectric materials and devices. It gives me a unique advantage in developing high-performance materials and devices by taking the “device-by-design” strategy. I work in three areas of interplay: (i) Biosensing and photodynamic therapy (precision medicine), (ii) photocatalysts and photoelectrochemical cells, and (iii) electrochemical energy storage. These areas are tied with fundamental discovery of charge transfer and energy transfer processes, and build on my interdisciplinary expertise in electrochemistry and plasmonics.
Biosensing and Point-of-care testing: It remains a challenge to improve the performance of biosensors in terms of selectivity, sensitivity, response time and reliability. We strive to utilize nanotechnology and nanomaterials to construct high-performance chemical sensors and biosensors. We attempt to achieve small size, easy integration into devices and low cost. We work on electrochemical sensors, plasmon-enhanced fluorescent sensors and surface-enhanced Raman scattering (SERS) sensors. In particular, we attempt to integrate sensors with microfluidic modules to create lab-on-chips (LOCs) for real-world sample applications. We strive to develop inexpensive portable devices as point-of-care (POC) tools for detection of proteins, DNA, pathogens, small molecules and heavy metals. For example, a SERS sensor based on a three-dimensional (3D) plasmonic nanostructure has been demonstrated for detection of vascular endothelial growth factor (VEGF) biomarker in clinical blood plasma taken from breast cancer patients. And a paper-based SERS lateral flow strip has been developed for measurement of neuron-specific enolase level in in clinical blood plasma samples taken from traumatic brain injury (TBI) patients.
Photodynamic therapy and bio-imaging: I am working on plasmon-enabled photodynamic therapy, which is logical extension from my research on plasmonics, photocatalysis and biosensing. Typically, organic dyes are used as photosensitizers in photodynamic therapy. Unfortunately, they suffer from photobleaching and degradation. For inorganic semiconductor photosensitizers, narrow bandgap semiconductors surfer from photodegradation while wide bandgap semiconductors can be excited by ultraviolet light or visible-light, which either do harm on health or have limited penetration. To solve these problems, we will develop plasmonic metal-inorganic semiconductor core-shell nanoparticles as photosensitizers. The plasmonic metal can be excited by near-infrared light in the first or second biological transparency window, which enable deep penetration. The plasmonic energy will transfer from the metal to the semiconductor. As a result, the semiconductor will generate radical oxygen species (ROS) or singlet oxygen species, which perform photodynamic therapy. Also, we will embed the near-infrared fluorescence or Raman report molecules into the core-shell nanoparticles. In this case, we can in vivo image the disease site and monitor the photodynamic therapy processes.
- PhD, Materials Science and Engineering, Zhejiang University, 1997
- Postdoctoral Research Fellow, University of Pittsburg, 1999-2001