Biomedical Microdevices

, Volume 12, Issue 6, pp 1051–1059

Microfluidic sedimentation cytometer for milk quality and bovine mastitis monitoring

Authors

  • Jose L. Garcia-Cordero
    • Biomedical Diagnostics Institute, National Centre for Sensor ResearchDublin City University
  • Louise M. Barrett
    • Biomedical Diagnostics Institute, National Centre for Sensor ResearchDublin City University
  • Richard O’Kennedy
    • Biomedical Diagnostics Institute, National Centre for Sensor ResearchDublin City University
    • Biomedical Diagnostics Institute, National Centre for Sensor ResearchDublin City University
Article

DOI: 10.1007/s10544-010-9459-5

Cite this article as:
Garcia-Cordero, J.L., Barrett, L.M., O’Kennedy, R. et al. Biomed Microdevices (2010) 12: 1051. doi:10.1007/s10544-010-9459-5

Abstract

We report a rapid, low-cost, portable microfluidic sedimentation cytometer (SeCy) for assessing the somatic cell count and fat content of milk in 15 min using a “sample-in, answer-out” approach. The system consists of 12 independent microfluidic devices, essentially flattened funnel structures, fabricated on the footprint of a single plastic compact disc (CD). Each funnel structure holds 150 μL of milk, has an inlet for milk filling and an outlet for air to escape, and ends in a narrow, closed-end microfluidic channel that facilitates packing of the cells into a column whose length is proportional to cell count. The closed-end channel provides accurate cell counts over the range 50,000–>3,000,000 cells per mL. The assay separates cells and fat globules based on their densities (by differential sedimentation), concentrating white cells in the closed-end channel near the outer rim of the CD for estimation of total “cell pellet” volume, while fat globules move toward the center of disc rotation, forming a fat “band” in the funnel. After adding milk to two or more microfluidic devices, the CD is loaded onto a custom-built reader unit that spins the disc for 15 min. Two low-cost microscopes in the reader image the centrifuged cell pellet and the fat band, providing a sufficiently accurate cell count to diagnose mastitis and measuring fat content as an indication of health and nutritional status.

Keywords

Bovine mastitisMilkCytometerCentrifugal microfluidicsSedimentationCell-counterSomatic cellsSample-to-answer device

Supplementary material

10544_2010_9459_MOESM1_ESM.pdf (2.8 mb)
ESM 1(PDF 2.76 MB)

Copyright information

© Springer Science+Business Media, LLC 2010