Journal: bioRxiv

Article Title: A Continuous, Low-Flow, and Multiplexing Pumping System for Microfluidics Applications

doi: 10.1101/2024.08.16.608339

Figure Lengend Snippet: Fluidic Multiplexing with Three-Way Solenoid Pinch Valves. A) Fluidic multiplexing (MUXing) schematics with 3-Way Pinch Valves: “wiring diagrams” and valve-state / output truth tables. *The 3 to 1 and 4 to 1 MUX schematics pictured are the optimal obtainable schematics using BEION pinch valves and Shore A 50 durometer hardness tubing, due to the internal solenoid spring being unable to fully compress more than one cross-section of Shore A 50 tubing in the OFF state. These schematics follow the Select N+1 rule, while optimal MUXes using different valves or softer tubing could follow the Select 2 to the N rule. B) i) Main use cases for fluidic MUXes, which are perturbation between sources (“digital” MUXing), and mixing of sources (“analog” MUXing). ii) Mixing diffusion computational fluid dynamic modeling, which shows the diffusion of infused inputs in tubing with three different MUXing cycle periods. iii) Quantitative representation of the data from part (ii). The behavior of the mole fraction can be further modeled by over-damped oscillators, whose dampening coefficients can predict when convergence at a mole fraction of 0.5 is reached. C) Setup and results of an experiment using a 3 to 1 MUX, a DSCPM unit, and dyed input solutions. The DSCPM infused from the three reservoirs at 15μL/min, while the MUX “mixed” the three inputs with a cycle period of 35 seconds.

Article Snippet: This is because the valves used for the DSCPM prototype (12V Three-Way Solenoid Pinch Valves from BEION/PreciGenome) cannot maintain the OFF state when pinching more than one cross-section of tubing.

Techniques: Multiplexing, Diffusion-based Assay