Fluorescent Imaging Cytometry and E.Coli Detection on a Cell-phone
We introduce the integration of imaging cytometry and fluorescent microscopy on a cell-phone using a compact, light-weight and cost-effective optofluidic attachment. In this cell-phone based optofluidic imaging cytometry platform, fluorescently labeled particles or cells of interest are continuously delivered to the imaging volume through a disposable micro-fluidic channel that is positioned above the existing camera unit of the cell-phone. The same micro-fluidic device also acts as a multi-layered optofluidic waveguide and efficiently guides the excitation light, which is butt-coupled from the side facets of our micro-fluidic channel using light-emitting diodes. Since the excitation of the sample volume occurs through guided waves that propagate perpendicular to the detection path, our cell-phone camera can record fluorescent movies of the specimens as they are flowing through the micro-channel. The digital frames of these fluorescent movies are then rapidly processed to quantify the count and the density of the labeled particles/cells within the target solution of interest.
Using a similar fluorescent imaging design and a capillary array, it is also possible to detect E. Coli in liquid samples. This fluorescent cell-phone based Escherichia coli (E. coli) detection utilizes anti-E. coli O157:H7 antibody functionalized glass capillaries as solid substrates to perform a quantum dot based sandwich assay for specific detection of E. coli O157:H7 in liquid samples.
-H. Zhu, O. Yaglidere, T. Su, D. Tseng, and A. Ozcan, Lab on a Chip (2010), DOI: 10.1039/C0LC00358A
-H. Zhu, S. Mavandadi, A.F. Coskun, O. Yaglidere, and A. Ozcan, Analytical Chemistry (2011), DOI:10.1021/AC201587A
-H. Zhu, U. Sikora, and A. Ozcan, Analyst (2012), DOI: 10.1039/C2AN35071H
Blood Analysis on a Cell-phone
This cell-phone based Blood Analyzer is a compact imaging cytometry platform installed on a cell-phone for the measurement of the density of red and white blood cells as well as hemoglobin concentration in human blood samples. Fluorescent and bright-field images of blood samples are captured using separate optical attachments to the cell-phone and are rapidly processed through a custom-developed smart application running on the phone for counting of blood cells and determining hemoglobin density. We evaluated the performance of this cell-phone based blood analysis platform using anonymous human blood samples and achieved comparable results to a standard bench-top hematology analyser. Test results can either be stored on the cell-phone memory or be transmitted to a central server, providing remote diagnosis opportunities even in field settings.
-H. Zhu, I. Sencan, J. Wong, S. Dimitrov, D. Tseng, K. Nagashima, and A. Ozcan, Lab on a Chip (2013), DOI:10.1039/C3LC41408F