Physical Sensors & Devices

Per- and polyfluoroalkyl substances (PFAS) are a class of persistent synthetic compounds, often called “forever chemicals,” that pose a significant threat to public health and the environment. Standard detection methods primarily rely on liquid chromatography and mass spectrometry [1], which is expensive, time-intensive, and requires trained personnel and laboratory infrastructure. While emerging approaches using metal-organic frameworks (MOFs), molecularly imprinted polymers, and lateral flow assays have been explored, they have yet to provide a solution that simultaneously offers part-...

Acoustic transducers are essential for object localization and environmental sensing. Conventional transducers rely on piezoelectric crystals, whose acoustic-electric response is fixed by the crystal lattice's inherent asymmetry and orientation. This results in static coupling behavior, necessitating bulky arrays of rigid elements with complex wiring and high computational demands for directional sensing. Here, we report a fundamentally new class of acoustic-electric coupling that emerges from topology-governed charge transport in 3D micro-architected piezoelectric metamaterials. Unlike...

Piezoelectric micromachined ultrasonic transducer (PMUT) arrays provide a compact and scalable platform for synthesizing programmable acoustic pressure fields. In this project, we investigate PMUT-enabled programmable microparticle self-assembly in fluidic environments using dynamically controlled ultrasonic standing waves. Unlike conventional cymatics, which relies on fixed vibrational modes of a single acoustic source, individually addressable PMUT elements enable active control of frequency, phase, and amplitude to generate reconfigurable pressure landscapes. By tailoring...

The Electrochemical Aptamer-based (E-AB) sensors provide continuous and real-time monitoring of specific target molecules, including proteins, antibiotics, neurotransmitters, and more. Due to the cost-effectiveness compared to enzyme sensing assays, E-AB platforms hold significant promise for point-of-care devices and precision medicine. However, sensitivity remains a challenge, particularly in the complicated environment, such as blood and serum. While research has achieved a noise level in the picoampere range, enhancing sensitivity is crucial for detecting trace amounts of certain...