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Microfluidic cell sorters have shown great potential to revolutionize the current technique of enriching rare cells. In the past decades, different microfluidic cell sorters have been developed by researchers for separating circulating tumor cells, T-cells, and other biological markers from blood samples. However, it typically takes months or even years to design these microfluidic cell sorters by hand. Thus, researchers tend to use computer simulation (usually finite element analysis) to verify their designs before fabrication and experimental testing. Despite this, conducting precision finite element analysis of microfluidic devices is computationally expensive and labor-intensive. To address this issue, we recently presented a microfluidic simulation method that can simulate the behavior of fluids and particles in some typical microfluidic chips instantaneously. Our method decomposes the chip into channels and intersections. The behavior of fluid in each channel is determined by leveraging analogies with electronic circuits, and the behavior of fluid and particles in each intersection is determined by querying a database containing 92,934 pre-simulated channel intersections. While this approach successfully predicts the behavior of complex microfluidic chips in a fraction of the time required by existing techniques, we nonetheless identified three major limitations with this method: (1) the library of pre-simulated channel intersections is unnecessarily large (only 2,072 of 92,934 were used); (2) the library contains only cross-shaped intersections (and no other intersection geometries); and (3) the range of fluid flow rates in the library is limited to 0 to 2 cm/s. To address these deficiencies, in this work we present an improved method for instantaneously simulating the trajectories of particles in microfluidic chips. Firstly, inspired by dynamic programming, our new method optimizes the generation of pre-simulated intersection units and avoids generating unnecessary simulations. Secondly, we constructed a cloud database (http://cloud.microfluidics.cc) to share our pre-simulated results and to let users become contributors and upload their simulation results into the cloud database as a benefit to the whole microfluidic simulation community. Lastly, we investigated the impact of different channel angles and different fluid flow rates on predicting the trajectories of particles. We found a wide range of device geometries and flow rates over which our existing simulation results can be extended without having to perform additional simulations. Our method should accelerate the simulation of particles in microfluidic chips and enable researchers to design new microfluidic cell sorter chips more efficiently.
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This content will become publicly available on November 19, 2025
Common Food-Wrap Film as a Cost-Effective and Readily Available Alternative to Thermoplastic Polyurethane (TPU) Membranes for Microfluidics On-Chip Valves and Pumps
Recently, there has been an increasing effort in developing new fabrication methods for rapid prototyping of microfluidic chips using laser cutting and 3D printing. However, although these approaches can readily generate rigid parts of the devices, it is not trivial to integrate flexible components (e.g. on-chip valve and/or pump membranes) within the same build. This has led to the recent adoption of thermoplastic polyurethane (TPU) membranes sandwiched between the rigid layers to introduce the necessary flexibility to the chips. Despite its utility, TPU is not without its challenges—it is relatively expensive and surprisingly difficult to source. To overcome these difficulties, our study introduces the use of common food wrapping film as a cost-effective and readily available alternative to TPU, demonstrating its compatibility in fabricating essential microfluidic components such as on-chip valves and peristaltic pumps. Our findings show that this alternative maintains the performance standards required for sophisticated microfluidic applications while significantly alleviating logistical and financial constraints. The results show high cyclability of the membrane, up to 850,000 in continuous testing conditions, at 1 Hz, while also can block the fluid flow at as low as 250 kPa. Regarding the micropumps, it was shown that adequate flow rate of around 4 μL/min can be achieved.
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- Award ID(s):
- 2141029
- PAR ID:
- 10574707
- Publisher / Repository:
- engrxiv
- Date Published:
- Format(s):
- Medium: X
- Institution:
- New Jersey Institute of Technology
- Sponsoring Org:
- National Science Foundation
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