Monitoring CD4 in Whole Blood with an Opto-fluidic Detector Based on Spatially Modulated Fluorescence Emission

We describe a new optical detection technique, termed spatially modulated fluorescence emission, that delivers high signal-to-noise discrimination without precision optics to enable a flow cytometer that can combine high performance, robustness, compactness, low cost, and ease of use. The detection technique is demonstrated with measurements of absolute CD4+ and percentage CD4 counts in human blood. Benchmarking against a commonly used commercial instrument for this test yields excellent agreement for both absolute CD4 and percentage CD4. (C) 2011 International Society for Advancement of Cytometry