A5042404908- Advanced Sensor and Energy Harvesting Materials
- Nanofabrication and Lithography Techniques
- Nanowire Synthesis and Applications
- Analytical Chemistry and Sensors
- RNA Interference and Gene Delivery
- Conducting polymers and applications
- Advanced biosensing and bioanalysis techniques
- Force Microscopy Techniques and Applications
- Nanoplatforms for cancer theranostics
- Molecular Junctions and Nanostructures
- Gold and Silver Nanoparticles Synthesis and Applications
- Neuroscience and Neural Engineering
- Advancements in Semiconductor Devices and Circuit Design
- 3D Printing in Biomedical Research
- Tactile and Sensory Interactions
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Electrochemical sensors and biosensors
- Microfluidic and Bio-sensing Technologies
- Advancements in Photolithography Techniques
- Quantum Dots Synthesis And Properties
- Nanocluster Synthesis and Applications
- Organic Light-Emitting Diodes Research
- Crystallography and molecular interactions
- Biochemical and Structural Characterization
Stanford University
2021-2025
University of California, Los Angeles
2015-2022
California NanoSystems Institute
2017-2022
Northwestern University
2017
International Institute for Nanotechnology
2017
Broad Center
2017
Beijing Institute of Technology
2014-2015
Transistor sensing in salt solutions Molecular binding to receptors on the surface of field-effect transistors (FETs) can be sensed through changes transconductance. However, saline typically used with biomolecules create an electrical double layer that masks any events occur within about 1 nanometer from surface. Nakatsuka et al. overcame this limitation by using large, negatively charged DNA stem loop structures that, upon ligand binding, cause conformational FET, even high ionic strength....
Artificial skin that simultaneously mimics sensory feedback and mechanical properties of natural holds substantial promise for next-generation robotic medical devices. However, achieving such a biomimetic system can seamlessly integrate with the human body remains challenge. Through rational design engineering material properties, device structures, architectures, we realized monolithic soft prosthetic electronic (e-skin). It is capable multimodal perception, neuromorphic pulse-train signal...
Wearable technologies for personalized monitoring require sensors that track biomarkers often present at low levels. Cortisol—a key stress biomarker—is in sweat nanomolar concentrations. Previous wearable sensing systems are limited to analytes the micromolar-millimolar ranges. To overcome this and other limitations, we developed a flexible field-effect transistor (FET) biosensor array exploits previously unreported cortisol aptamer coupled nanometer-thin-film In2O3 FETs. Cortisol levels...
Implantable aptamer transistor probes for in vivo neurotransmitter monitoring advance brain activity recording.
We demonstrate straightforward fabrication of highly sensitive biosensor arrays based on field-effect transistors, using an efficient high-throughput, large-area patterning process. Chemical lift-off lithography is used to construct transistor with high spatial precision suitable for the both micrometer- and nanometer-scale devices. Sol–gel processing deposit ultrathin (∼4 nm) In2O3 films as semiconducting channel layers. The aqueous sol–gel process produces uniform coatings thicknesses a...
An efficient nonviral platform for high-throughput and subcellular precision targeted intracellular delivery of nucleic acids in cell culture based on magnetic nanospears is reported. These are made Au/Ni/Si (∼5 μm length with tip diameters <50 nm) fabricated by nanosphere lithography metal deposition. A magnet used to direct the mechanical motion a single nanospear, enabling precise control position three-dimensional rotation. were further functionalized enhanced green fluorescent protein...
While three-dimensional (3D) configurable hierarchical nanostructures have wide ranging applications in electronics, biology, and optics, finding scalable approaches remains a challenge. We report robust general strategy called multiple-patterning nanosphere lithography (MP-NSL) for the fabrication of periodic 3D highly tunable manner. This nanofabrication technique exploits selected repeated etching polymer nanospheres that serve as resists can be shaped parallel each processing step. The...
An efficient ligand exchange strategy for aqueous phase transfer of hydrophobic CuInS2/ZnS quantum dots was developed by employing glutathione (GSH) and mercaptopropionic acid (MPA) as the ligands. The whole process takes less than 20 min can be scaled up to gram amount. material characterizations show that final soluble samples are solely capped with GSH on surface. Importantly, these GSH-capped have small size (hydrodynamic diameter <10 nm), moderate fluorescent properties (up 34%) well...
The rapid development of fluorescence imaging technologies requires concurrent improvements in the performance fluorescent probes. Quantum dots have been extensively used as an probe various research areas because their inherent advantages based on unique optical and electronic properties. However, clinical translation has limited by potential toxicity especially from cadmium. Here, a versatile bioimaging is developed using highly luminescent cadmium‐free CuInSe 2 /ZnS core/shell quantum...
Determination of the amino acid phenylalanine is important for lifelong disease management in patients with phenylketonuria, a genetic disorder which accumulates and persists at levels that alter brain development cause permanent neurological damage cognitive dysfunction. Recent approaches treating phenylketonuria focus on injectable medications efficiently break down but sometimes result detrimentally low levels. We have identified new DNA aptamers two formats, initially as fluorescent...
Spin selectivity in photo-emission from ferromagnetic substrates functionalized with chiral organic films was analyzed by ultraviolet photoelectron spectroscopy at room temperature. Using radiation photon energy greater than the ionization potential of adsorbed molecules, photoelectrons were collected that originated both underlying and films, kinetic energies range ca. 0–18 eV. We investigated composed self-assembled monolayers α-helical peptides electrostatically protein, bovine serum...
Flexible sensors are essential for advancing implantable and wearable bioelectronics toward monitoring chemical signals within on the body. Developing biosensors multiple neurotransmitters in real time represents a key vivo application that will increase understanding of information encoded brain neurochemical fluxes. Here, arrays devices having In2O3 nanoribbon field-effect transistors (FETs) were fabricated 1.4-μm-thick polyethylene terephthalate (PET) substrates using shadow mask...
Conventional photolithography, due to its scalability, robustness, and straightforward processes, has been widely applied micro- nanostructure manufacturing in electronics, optics, biology. However, optical diffraction limits the ultimate resolution of conventional which hinders potential nanoscale patterning for broader applications. Here, we introduce a derivative photolithography called dual-layer (DLPL), is based on controlled exposure development overlapping positive negative...
Abstract Dielectric elastomer actuators (DEAs) offer versatile applications including haptics, soft robotics and smart lenses. However, due to the lack of conductive electrodes with low modulus high stretchability, their use is limited by nonsolid electrodes, hindering integration other systems. In this study, transparent patternable solid achieving actuation performance comparable a commonly used non‐solid counterpart (e.g., carbon grease), stretchable conducting polymer composed PEDOT:PSS...
Three tetra-aryl substituted 1,3-butadiene derivatives with aggregation enhanced emission (AEE) and mechanochromic fluorescence behavior have been rationally designed synthesized. The results suggest an effective design strategy for developing diverse materials induced (AIE) significant performance by employing D-π-A structures large dipole moments.
Abstract Wearable electroenzymatic sensors enable monitoring of clinically informative biomolecules in epidermally retrievable biofluids. Conventional wearable enzymatic utilize Prussian Blue (a redox mediator) to achieve selectivity against electroactive interferents. However, the use presents fundamental challenges including: 1) susceptibility sensor response dynamic concentration variation ionic species and 2) poor operational stability due degradation its framework. As an alternative...
Wafer-scale nanoribbon field-effect transistor (FET) biosensors fabricated by straightforward top-down processes are demonstrated as sensing platforms with high sensitivity to a broad range of biological targets. Nanoribbons 350 nm widths (700 pitch) were patterned chemical lift-off lithography using high-throughput, low-cost commercial digital versatile disks (DVDs) masters. Lift-off was also used pattern ribbons 2 μm or 20 (4 40 pitches, respectively) masters photolithography. For all...
We designed and fabricated large arrays of polymer pens having sub-20 nm tips to perform chemical lift-off lithography (CLL). As such, we developed a hybrid patterning strategy called polymer-pen (PPCLL). demonstrated PPCLL using pyramidal v-shaped arrays. Associated simulations revealed nanometer-scale quadratic relationship between contact line widths the two other variables: base vertical compression distances. devised stamp support system consisting interspersed flat-tipped that are...
Efficient intracellular delivery of biomolecules into cells that grow in suspension is great interest for biomedical research, such as applications cancer immunotherapy. Although tremendous effort has been expended, it remains challenging existing transfer platforms to deliver materials efficiently cells. Here, we demonstrate a high-efficiency photothermal approach using sharp nanoscale metal-coated tips positioned at the edge microwells, which provide controllable membrane disruption each...
Nanoribbon- and nanowire-based field-effect transistors (FETs) have attracted significant attention due to their high surface-to-volume ratios, which make them effective as chemical biological sensors. However, the conventional nanofabrication of these devices is challenging costly, posing a major barrier widespread use. We report high-throughput approach for producing arrays ultrathin (∼3 nm) In2O3 nanoribbon FETs at wafer scale. Uniform films semiconducting were prepared on Si/SiO2...