Our research activity focuses on the field of nanobioelectronic which is a rapidly developing field aimed at integrating nano- and biomaterials with electronic transducers. Our highly multidisciplinary research combines fundamental studies from different disciplines with forward-looking engineering efforts.
Current research projects:
- Synthetic nanomotors, nanomachines and nanorobots.
- Epidermal tattoo- and textile based wearable sensors
- Nanoscale motion control
- Nanomaterial-based bioassays
- Flexible, stretchable and self-healed printable wearable devices
- Motion-based biosensing and bioseparations
- Advanced glucose monitoring for diabetes management
- Development of DNA and protein biosensors
- Fuel cells and biofuel cells
- On-body wearable power sources (energy harvesting).
- Advanced materials for energy applications
- Acoustic microcannons and nanobullets
- Forensic detection of explosives and gunshot residues
- Non-invasive and minimally-invasive monitoring
- Advanced materials for autonomous systems
- Biomedical and environmental applications of nanomachines.
- Remote sensors for environmental monitoring and security surveillance
The use of nanomotors to power nanomachines, nanorobots and nanofactories is one of the most exciting challenges facing nanotechnology. Nanoscale biomotors, based on spontaneous reactions of energy-rich biomolecules (e.g., ATP), are common in nature. Such mechanical function of biological motors has provided an inspiration for the development of manmade nanomachines, operating on locally supplied fuels and performing various tasks. Efficient energy conversion is crucial for the successful use of nanomotors as power-generating engines for nanoscale devices.
The UCSD Nanobioelectronic team is involved in the design of versatile and powerful energy-efficient nanomachines and nanorobots, along with sophisticated schemes for their precise motion control for broad range of practical biomedical and environmental applications, ranging from microbullets that could roam the body and deliver medicine directly to a cancerous tumor or other diseased tissue to nanosubmarines for cleanup of oil spills and capture and destroy chemical and biological agents. Our group has made pioneering contributions towards the design of powerful micro/nano motors that rely on local chemical fuel or on external ultrasound and magnetic actuation, and demonstrated the first example of operating nanomotors in living organisms (Figure 3). Our team has pioneered variety of applications of nanomachines ranging from directed drug delivery, isolation of target biomolecules and cells, accelerated detoxification processes, and was first to demonstrate the application of micromachines in living organisms.
Our recent efforts have been directed at exploring the use of the sample matrix itself (media or constituents) as the fuel, thus obviating the need for adding an external fuel (e.g., Figure 2). Given the enormous interest in this cutting-edge research area, we expect exciting new developments in the near future. These future applications of man-made nanomachines and nanorobots will be limited only by our imagination. See Figures 7-9 below.
Sensors are small devices that provide real-time, on-site detection and analysis and often eliminate the need for sample collection, preparation and laboratory analysis. Such devices rely on the judicious and intimate coupling of a chemical or biological recognition layer and a physical transducer (e.g. electrode, fiber optic). The goal is to convert the selective chemical or biological recognition event into a useful electrical signal. The development of advanced chemical sensors and biosensors thus requires proper attention to both the recognition layer and the physical transducer, as well as to the coupling of these recognition and transduction events. We are exploring the fundamental aspects of the recognition and transduction events, developing and characterizing new coating materials and electrode transducers, designing new microsensors for clinical diagnostics, environmental monitoring, security surveillance, or industrial process control, exploring flexible and stretchable (Figure 4) wearable devices for non-invasive on-body sensing (e.g., tattoo-based sensors; Figures 1,6 and 11), developing 'smart' Sense/Act logic-based closed-loop devices (e.g., Figure 5), new interfaces for ultrasensitive bioaffinity (DNA, protein) assays, enhancing biodetection through the use of novel materials (e.g., nanowires, nanoparticles) and build compact instruments for field measurement.
The creation of epidermal sensing devices able to conform to the contours of the human anatomy is currently receiving considerable attention in our labs towards non-invasive chemical monitoring. The above photograph gives an insight into the various wearable sensors being developed in our labs for detecting several important analytes. Such skin-worn wearable sensors can yield significant insights into the overall health status of the wearer in connection to diverse healthcare, fitness and military applications (Figure 1, 12, 14). Wearable biofuel cells are being developed for powering these on-body sensors (Figure 13). In addition, advanced sensors for 'on-the-spot' forensic applications are being developed towards field identification of explosives or gunshot residues (Figure 12). We demonstrated all printed highly stretchable electrochemical sensors and biofuel cells that can withstand extreme mechanical strains with negligible effect on their structural integrity and electrochemical performance. Advanced self-healing materials are integrated into our wearable electrochemical devices to prevent structural fractures and augments their longevity.
Towards logic-activated therapeutic intervention (Angew Chemie, 2012).
Figure 6. Accelerated intracellular gene silencing based on acoustically propelled nanowire motors (ACS Nano 2016).
Figure 7. Electrochemical tattoo biosensor for real-time non-invasive lactate monitoring during fitness activity (Anal Chem 2013).
The research has been supported by numerous grants from various federal agencies (NSF, NIH, ONR, DTRA, CDC, EPA, DOE, DOD, NASA, Army, Navy, Sandia, USDA, Battelle, Dept. of Interior, Dept. of Justice) and industrial sponsors (Millipore, Procter & Gamble (PG), Motorola, Kodak, Dow, Dupont, Lifescan, IL, Cygness, Jockey, Novo Nordisk, Electrozyme, Pioneer, Medisense, ETG) and other organizations (ACS-PRF, American Heart Association).
We are interested in collaborating with industrial or governmental partners for the development of solutions to practical, analytical and sensor problems. Our thick-film microfabrication facility also provides a tailor-made preparation of screen-printed electrodes and printable electronic flexible devices.
Our research is constantly resulting in new patented technology which can be licensed. Please contact us for more details of how you can access our patents.
Undergraduate and Graduate Research Assistants
If you are interested in undergraduate and graduate research opportunity please contact Joseph Wang directly.