title: Streak Imaging Flow Cytometer for Rare Cell Analysis.
abstract: There is a need for simple and affordable techniques for cytology for clinical applications, especially for point-of-care (POC) medical diagnostics in resource-poor settings. However, this often requires adapting expensive and complex laboratory-based techniques that often require significant power and are too massive to transport easily. One such technique is flow cytometry, which has great potential for modification due to the simplicity of the principle of optical tracking of cells. However, it is limited in that regard due to the flow focusing technique used to isolate cells for optical detection. This technique inherently reduces the flow rate and is therefore unsuitable for rapid detection of rare cells which require large volume for analysis.To address these limitations, we developed a low-cost, mobile flow cytometer based on streak imaging. In our new configuration we utilize a simple webcam for optical detection over a large area associated with a wide-field flow cell. The new flow cell is capable of larger volume and higher throughput fluorescence detection of rare cells than the flow cells with hydrodynamic focusing used in conventional flow cytometry. The webcam is an inexpensive, commercially available system, and for fluorescence analysis we use a 1 W 450 nm blue laser to excite Syto-9 stained cells with emission at 535 nm. We were able to detect low concentrations of stained cells at high flow rates of 10 mL/min, which is suitable for rapidly analyzing larger specimen volumes to detect rare cells at appropriate concentration levels. The new rapid detection capabilities, combined with the simplicity and low cost of this device, suggest a potential for clinical POC flow cytometry in resource-poor settings associated with global health.
authors.affiliation: Center for Devices and Radiological Health, FDA, Silver Spring, MD, 20993, USA.
authors.forename: Joshua
authors.initials: J
authors.lastname: Balsam
authors.affiliation: University of Maryland, College Park, MD, 20742, USA.
authors.forename: Hugh Alan
authors.initials: HA
authors.lastname: Bruck
authors.affiliation: National Cancer Institute, National Institutes of Health, Rockville, MD, 20850, USA.
authors.forename: Miguel
authors.initials: M
authors.lastname: Ossandon
authors.affiliation: National Cancer Institute, National Institutes of Health, Rockville, MD, 20850, USA.
authors.forename: Ben
authors.initials: B
authors.lastname: Prickril
authors.affiliation: National Cancer Institute, National Institutes of Health, Rockville, MD, 20850, USA. rasoolya@mail.nih.gov.
authors.forename: Avraham
authors.initials: A
authors.lastname: Rasooly
mesh_terms: D018929:Cell Culture Techniques; D002460:Cell Line; D058948:Cell Tracking / Q000295:instrumentation / Q000379:methods*; D004867:Equipment Design; D005434:Flow Cytometry / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D055096:Optical Devices; D019095:Point-of-Care Systems; D059629:Signal-To-Noise Ratio; D013223:Statistics as Topic; D057211:Webcasts as Topic
keywords: Flow cytometry; Fluidics; Fluorescence detection; POC; Rare cells; Webcam