Characterization of organic fouling on thermal bubble-driven micro-pumps

Abstract

Thermal bubble-driven micro-pumps are an upcoming micro-actuator technology that can be directly integrated into micro/mesofluidic channels, have no moving parts, and leverage existing mass production fabrication approaches. These micro-pumps consist of a high-power micro-resistor that boils fluid in microseconds to create a high-pressure vapor bubble which performs mechanical work. As such, these micro-pumps hold great promise for micro/mesofluidic systems such as lab-on-a-chip technologies. However, to date, no current work has studied the interaction of these micro-pumps with biofluids such as blood and protein-rich fluids. In this study, the effects of organic fouling due to egg albumin and bovine whole blood are characterized using stroboscopic high-speed imaging and a custom deep learning neural network based on transfer learning of RESNET-18. It was found that the growth of a fouling film inhibited vapor bubble formation. A new metric to quantify the extent of fouling was proposed using the decrease in vapor bubble area as a function of the number of micro-pump firing events. Fouling due to egg albumin and bovine whole blood was found to significantly degrade pump performance as well as the lifetime of thermal bubble-driven micro-pumps to less than 104 firings, which may necessitate the use of protective thin film coatings to prevent the buildup of a fouling layer.

BibTeX

@article{hayes2024characterization,
  title = {Characterization of organic fouling on thermal bubble-driven micro-pumps},
  author = {Hayes, Brandon and Murphy, Cillian and Marquez Rubio, Janeth and Solis, Daimean and Jayaram, Kaushik and MacCurdy, Robert},
  journal = {Biofouling},
  pages = {1--15},
  year = {2024},
  publisher = {Taylor \& Francis},
  url = {https://doi.org/10.1080/08927014.2024.2353034},
  doi = {https://doi.org/10.1080/08927014.2024.2353034},
}