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Hsu, M.-C.

Publications and source records attributed to Hsu, M.-C..

2 recordsLinked to original sources

Modular Integration of Impedance Sensing for Real-Time Assessment of Barrier Integrity

Microphysiological systems (MPS) are essential for modeling tissue barriers, yet integrating electrical readouts often requires permanently sealed microfluidic architectures that limit access to open-well (direct-access) workflows used in bioscience laboratories. To resolve this issue, we present a modular approach in which functional components are added and removed from a standard MPS core using a magnetic interface. This design preserves compatibility with established open-well protocols for seeding and downstream analysis, while microfluidic perfusion or electrical sensing capabilities are added only when needed. We demonstrate this approach with an impedance-sensing module that enables continuous impedance measurements to assess barrier function. By fitting spectra to an equivalent circuit model, we quantify junctional and non-junctional electrical contributions to barrier integrity over time, alongside conventional single-frequency TEER, and complementary permeability and imaging readouts. We apply this platform across three representative use cases, including LPS-induced disruption, shear stress-mediated strengthening, and compatibility with barrier models formed above a 3D hydrogel matrix.

bioengineering↗

A Miniaturized 3D-Printed Pressure Regulator (μPR) for Microfluidic Cell Culture Applications

Controlled fluid flows are the hallmark feature of microfluidic culture systems and provide precise definition over the biophysical and biochemical microenvironment. Flow control is commonly achieved using displacement-based (e.g., syringe or peristaltic pumps) or pressure-based techniques. These methods offer complex flow capabilities but can be challenging to integrate into incubators or other confined environments due to their large form factors and accompanying peripheral equipment. Since many microfluidic cell culture studies use a single controlled flow rate to maintain or stimulate cells, a portable flow control platform that fits easily into an incubator will benefit the microfluidic community. Here, we demonstrate that a tunable, 3D printed micro pressure regulator (PR), combined with a battery-powered miniature air pump, can operate as a stand-alone pneumatic flow control platform for microfluidic applications. We detail the design and fabrication of the PR and demonstrate: i) a tunable outlet pressure range relevant for microfluidic applications (1-10 kPa), ii) highlight dynamic control in a microfluidic network, and iii) maintain human umbilical vein endothelial cells (HUVECs) in a multi-compartment membrane-based culture device under continuous flow conditions. We anticipate that our 3D-printed fabrication approach and open access designs will allow other laboratories to rapidly customize PRs to support a broad range of applications.

bioengineering↗