This disclosure is directed to methods and devices (300) associated with Point of Care medical testing and diagnostics. More specifically, methods and devices are described which provide a quick and streamlined way to prepare blood samples for analysis using flow cytometers, microscopes, and other analysis platforms. The benefits include a reduction in the time, resources, and expertise needed for preparing those blood samples without compromising the accuracy and efficacy of diagnosing diseases or identifying specific particulates from those blood samples.