I developed a mechanical actuator for an organ-on-a-chip platform, realized from parts designed and 3D printed in the lab as well as an integrated electronic control system based on Arduino and servo-motors.
GitHub: https://github.com/LaboratoryOpticsBiosciences/oscillator
Introduction
For the monitoring of many pathologies, it is essential to develop quantitative assays to probe complex biological processes from the molecular to the organ scale. This is particularly true for rapidly progressing glomerulonephritis (RPGN) and segmental and focal hyalinosis (SFH), which can cause dedifferentiation and uncontrolled migration of specialized cells through a complex interplay between different molecular cues. The lack of devices to probe cellular and molecular responses in a relevant in-vitro environment has so far hindered the mechanistic understanding of this phenomenon.
Based on the microsystem already developed in the laboratory for the co-culture of renal cells recapitulating a renal glomerulus (Figure below), I will develop a mechanical actuation system that allows the recirculation of the culture medium in the system in a permanent manner.
The mechanical actuation system will be realized from parts designed and 3D printed in the laboratory as well as an integrated electronic control system based on arduino and servo- motors. The system will have to satisfy certain requirements; portability, waterproofness and size related to the use in sterile cell culture environment.
We want to recirculate the culture medium in a permanent manner in the system. So, we thought of building an oscillator that will perturb the hydrostatic equilibrium by rotating the system between an angle α and −α.
After reaching the hydrostatic equilibrium at −α, we put the system at an angle α (Figure below).
After long calculations (see Internship Report), we obtain the following duration needed to reach the hydrostatic equilibrium after perturbing it: 580 seconds.
Now, we design an oscillator that would allow us to perturb the hydrostatic equilibrium as indicated above. We design the parts on SolidWorks, before 3D printing and assembling them. (See drawings in Media)
Now we use a waterproof servomotor (sg90) that we connect to an Arduino UNO, to realize the oscillations of the plate. We activate the motor and control the oscillation period using a touch screen (4d systems). We also print the number of oscillations done on that screen. The code can be found in the GitHub.
After assembling all the parts together and adding adding the electronics we get the fol- lowing final product which is an oscillator that will stay stationary for a given period of time controlled by the touch screen.
Conceptual Design
