Abstract
The optofluidic microscope (OFM) is a lensless, low-cost and highly compact on-chip device that can enable high-resolution microscopy imaging. The OFM performs imaging by flowing/scanning the target objects across a slanted hole array; by measuring the time-varying light transmission changes through the holes, we can then render images of the target objects at a resolution that is comparable to the holes’ size. This paper reports the adaptation of the OFM for imaging Giardia lamblia trophozoites and cysts, a disease-causing parasite species that is commonly found in poor-quality water sources. We also describe our study of the impact of pressure-based flow and DC electrokinetic-based flow in controlling the flow motion of Giardia cysts—rotation-free translation of the parasite is important for good OFM image acquisition. Finally, we report the successful microscopy imaging of both Giardia trophozoites and cysts with an OFM that has a focal plane resolution of 0.8 microns.
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Acknowledgements
The authors appreciate the generous help and discussions from Dr. Xin Heng, Guoan Zheng, Sean Pang and Dr. Jigang Wu. This work is supported by DARPA Center for Optofluidic Integration (California Institute of Technology), NIH R21EB008867-01, and Coulter Foundation Early Career Award. Lap Man Lee is thankful for the financial support from the Croucher Foundation Scholarship (Hong Kong).
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Lee, L.M., Cui, X. & Yang, C. The application of on-chip optofluidic microscopy for imaging Giardia lamblia trophozoites and cysts. Biomed Microdevices 11, 951 (2009). https://doi.org/10.1007/s10544-009-9312-x
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DOI: https://doi.org/10.1007/s10544-009-9312-x