Liwei Lin (Advisor)

We report a self-healable, flexible, and multimodal sweat sensor based on laser-induced graphene electrodes for healthcare monitoring application. A transfer printing and laser engraving process has been developed to conduct a high-throughput patterning process of various materials on a self-healable substrate. The prototype device is capable of simultaneous detection of pH, uric acid, and tyrosine, which are important indicators for skin and metabolic disorders. Furthermore, this work has made advancements as compared with the state-of-art works: (1) maintaining sensitivity under large...

This paper reports an ultrasonic 3D object detector with > 1 meter range based on an AlN piezoelectric micromachined ultrasonic transducers (pMUTs) chip. Compared with the state-of-art technologies, three distinctive advancements have been achieved: (1) more than 1-meter in sensing distance enabled by a bimorph dual electrode pMUT design; (2) small form factor (6×6 mm2) and a more than 135o field of view; (3) capability of real time 3D object detection with up to 125 fps (frames per second) based on the scheme of ultrasound beamforming. As such, this work could open up a new class of...

The current clinical protocol to conduct a bacterial antibiotic susceptibility test (AST) requires at least 18 hours, and cannot be accomplished during a single visit for patients. Here, a new method based on the technique of CRISPR-Cas12a is utilized to accomplish a bacterial genotypic AST within one hour with good accuracy. Two amplification approaches are employed and compared: (1) enriching the bacterial concentration by culturing in growth media; and (2) amplifying target DNA from raw samples by recombinase polymerase amplification (RPA). The results show that CRISPR combined with RPA...

Microfluidic concentration gradient generators (µ-CGGs) have been utilized to identify optimal drug compositions through antimicrobial susceptibility testing (AST) for the treatment of antimicrobial-resistant (AMR) infections. Conventional µ-CGGs fabricated via photolithography-based micromachining processes, however, are fundamentally limited to two-dimensional fluidic routing, such that only two distinct antimicrobial drugs can be tested at once. This work addresses this limitation by employing Multijet-3D printed microchannel networks capable of fluidic routing in three dimensions to...