Despite having widespread application in the biomedical sciences, flow cytometers have several limitations that prevent their application to point-of-care (POC) diagnostics in resource-limited environments. 3D printing provides a cost-effective approach to improve the accessibility of POC devices in resource-limited environments. Towards this goal, we introduce a 3D-printed imaging platform (3DPIP) capable of accurately counting particles and perform fluorescence microscopy. In our 3DPIP, captured microscopic images of particle flow are processed on a custom developed particle counter code to provide a particle count. This prototype uses a machine vision-based algorithm to identify particles from captured flow images and is flexible enough to allow for labeled and label-free particle counting. Additionally, the particle counter code returns particle coordinates with respect to time which can further be used to perform particle image velocimetry. These results can help estimate forces acting on particles, and identify and sort different types of cells/particles. We evaluated the performance of this prototype by counting 10 μm polystyrene particles diluted in deionized water at different concentrations and comparing the results with a commercial Beckman-Coulter Z2 particle counter. The 3DPIP can count particle concentrations down to ∼100 particles per mL with a standard deviation of ±20 particles, which is comparablemore »
A NEW MICROFLUIDIC DEVICE INTEGRATED WITH QUARTZ CRYSTAL MICROBALANCE TO MEASURE COLLOIDAL PARTICLE ADHESION
Polystyrene particles simulating bacteria flow down a micro-channel in the presence of potassium chloride solution. Depending on the ionic concentration or flow rates, portion of the particles are trapped on the glass substrate due to intrinsic surface forces. A novel quartz crystal microbalance (QCM) is built into the microfluidic device to track the real-time particle deposition by shift of the resonance frequency. The new technique is promising to quantify water filtration.
- Award ID(s):
- 2130716
- Publication Date:
- NSF-PAR ID:
- 10350792
- Journal Name:
- Proceedings of the ASME 2021 International Mechanical Engineering Congress and Exposition
- Volume:
- 5
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Publisher's Version of Record
- https://doi.org/10.1115/IMECE2021-73099
