Research

Our research explores the detection of harmful chemicals that are a threat to the environment and human health, looks inside the body for markers or presence of disease and seeks to detection of human-made threats. 

Our areas of investigation include:  

• Biosensors. We develop label-free imaging tools and methods and apply them for biomarker research, drug discovery and disease diagnosis.  

Our research is focused on four major directions: 

• In-situ imaging and measuring single cell and subcellular activities in live cells, including membrane protein binding kinetics, cellular signal pathway dynamics, ion channel events and organelle activities. 
• Detecting and imaging single small molecules, proteins, viruses and bacteria. 
• Developing super resolution plasmonic-based imaging platform. 
• Measuring and imaging electrochemical properties of nanomaterials. 

Core technology:  

• Plasmonic-based electrochemical impedance microscopy (P-EIM), which can detect electrochemical impedance signals optically. In P-EIM, we take advantage of the high sensitivity of surface plasmonic resonance (SPR) to detect surface impedance and electrochemical signals with high spatial and temporal resolution, which cannot be realized by other electrochemical methods. Furthermore, the P-EIM system can be built on standard inverted fluorescence microscopy, which enables in-situ multifunctional imaging of the sample and can simultaneously obtain transmitted, fluorescence, SPR and P-EIM images of target samples. This feature allows us to combine the advantages of both labeled and label-free imaging in one system. Our latest breakthrough in this area is plasmonic scattering microscopy for label-free single protein binding kinetic detection. 
• In addition to P-EIM, we are interested in other label-free detection technologies and has developed several of them, including  
• Charge sensitive optical detection for detection of small molecule binding kinetics in a microplate compatible platform 
• Nano-oscillators, viral-oscillators and single protein oscillators for charge-based detection of small molecule interactions  
• Mechanical amplified detection of molecular interactions (MADMI), for in-situ detection of membrane protein binding kinetics on cell surface via quantification of binding induced cell membrane deformation. 
• Large volume scattering microscopy, for direct antimicrobial susceptibility test in urine sample 
• Digital immunoassay for rapid biomarker detection with image based digital counting of individual binding events. 
  • Funding sources: NIH, NSF, W.M. Keck Foundation, The Gordon and Betty Moore Foundation, Virginia G. Piper Charitable Trust, Amgen Inc., Genentech Inc. 
• Chemical sensors. Our research bridges the gap between science and real-world needs, by transforming new fundamental chemical sensing principles into practical solutions. We develop low cost, portable, and easy-to-use tools that can empower users with minimal training to perform simple diagnosis and disease management. Our devices can report chemical biomarkers non-invasively, and body exposure to pollutants. 

Our efforts focus on the creation of 

• Sensitive and selective chemical sensors. 

• Smart sample collection systems. 
• Unambiguous calibration methods. 
• Robust sensors’ signal processing. 
• Easy-to-use interfaces.  

We bind these capabilities to smart phones, thereby increasing resources for mobile health. Our team is a multidisciplinary group of enthusiastic engineers, chemists, physicists and health care professionals. Our mission is to enable people to take responsibility for their personal health or the health of their loved ones. 

Funding source: NIH, NSF, Flinn Foundation 

• Protein microarrays. We are developing technology to mass produce better and less expensive protein microarrays, making them more readily accessible to broad research and health care communities. Protein microarrays have the greatest prospects to revolutionize molecular diagnostics for early detection, diagnosis, treatment, prognosis and monitoring clinical response.  

We are combining several technologies to develop an innovative method to mass produce faster, better and cheaper protein microarrays based on printing arrays of cDNA templates onto an array of nanowells and expressing proteins in situ, from the templates, in the nanowells. We have developed technology to rapidly fill the array of nanowells with reagent and seal them into isolated chemical reaction chambers. By making high-quality protein microarrays more readily assessable, we will help unlock their true potential for research and clinical application.   

This work is supported by Department of Health and Human Services, National Institutes of Health and National Institute of General Medical Sciences, grant number: 5R42GM106704-04. 

• Bionanoelectronics. We focus on the design and preparation of novel nanomaterials with unique structures and characteristics for high performance electronics and biosensing applications.  

This includes:  

• Rational synthesis and assembly of 0-D and 1-D metal/semiconductor materials into devices and structures that match the length scales of the cellular and molecule processes key to cell metabolism and communication. 

• Studies of the fundamental chemical and physical properties of such materials/structures with the emphasis on pushing beyond the limit of conventional detection of cell activities and molecular interactions. 

• Prototyping bio-probes that can be integrated with live cell network/tissues for in vivo monitoring and stimulation applications. Qing’s recent work highlights novel nanowire-based biosensors interfaced with live cells/cell networks, including development of ultrasmall and multiplexed probes as new tools for fundamental research of extra- and intracellular processes, creating hybrid structures of nanoscale electronics and living cell networks/tissues for bidirectional communication and biomimetic information processing. 

For more details, please visit Qing’s Research Lab. 

Our team creates new enabling tools for biomedical and environmental health research, develops wireless personal sensors for mobile health solutions and explores fundamental phenomena of nature at the single molecule level for next-generation detection technologies.