Opto-Microfluidics for Monitoring Salinity and Temperature of Sea Water

Authors

  • Daiying Zhang Department of Physics and Physical Oceanography, Memorial University of Newfoundland, St. John’s, NL A1B 3X7, Canada
  • Liqiu Men Department of Physics and Physical Oceanography, Memorial University of Newfoundland, St. John’s, NL A1B 3X7, Canada
  • Qiying Chen Department of Physics and Physical Oceanography, Memorial University of Newfoundland, St. John’s, NL A1B 3X7, Canada

Abstract

The success of ocean observation relies on effective monitoring technologies with increased functionalities, minimized size, and reduced cost, which can only be achieved through the development of new technologies. Opto-microfluidics has been increasingly recognized as powerful technologies to realize miniaturized devices for environmental monitoring, biological analyses, and chemical syntheses. By combining microfluidics and optics technologies, roomful laboratory equipment can be integrated into a palm-size chip with merits of versatile functionalities, compactness, minimized waste, and low cost. These opto-microfluidic systems are promising for applications in ocean observation.

In this study, opto-microfluidic devices for monitoring salinity and temperature of liquids are proposed and demonstrated with ultrafast laser fabrication and two-photon polymerization techniques. By applying femtosecond lasers as powerful tools to achieve laser microfabrication with unprecedented high precision and quality, a Mach-Zehnder interferometer (MZI) has been fabricated and integrated into a microchannel as a miniaturized opto-microfluidic system. When saline solution or sea water is introduced to the microchannel, different phase shifts in the MZI can be resulted, which allow determination of the salinity and temperature of the solution from output optical spectra and intensities of the MZI corresponding to different phase shifts. The sensitivities of salinity and temperature have been found to be 215.744 nm/RIU and 0.519 nm/oC for the opto-microfluidic systems developed in this study, respectively. The results demonstrate the practicability of opto-microfluidic devices for real-time salinity and temperature monitoring of sea water in harsh environment.

Downloads

Published

2014-08-04

Issue

Proceedings of the International Conference on Marine and Freshwater Environments (iMFE 2014) - Our Water, Our Future

Section

Ocean Observation and Pollution Mitigation (OOP)

License

Authors who publish with this conference agree to the following terms: Authors retain copyright and grant the conference right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this conference. Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the conference's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this conference. Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).