Article

An in-line microfluidic blood sampling interface between patients and saline infusion systems.

Microsystems and BioMEMS Laboratory, Department of Electrical and Computer Engineering, University of Cincinnati, Cincinnati, OH 45221, USA.
Biomedical Microdevices (Impact Factor: 2.72). 04/2011; 13(4):661-9. DOI: 10.1007/s10544-011-9536-4
Source: PubMed

ABSTRACT This work seeks to extend the utility of microfluidics to conventional blood sampling aperati. Daily medical care of hospitalized patients demands repeated needle punctures or interfacing with a catheter to collect blood samples. Large, research grade systems can autonomously sample blood from laboratory animals; however, a disposable aperatus that can be used to repeatedly sample blood from hospitalized patients does not exist. We have designed, fabricated and demonstrated a 3-layered rigid polymer microfluidic blood sampling device with integrated polymer pinch valves for placement in-line between a patient and a saline infusion system. The blood sampler we designed seeks to mitigate sample cross contamination, reduce risks of microbial contamination associated with invasive blood sampling and improve technical ease of blood sampling. Clinical laboratory tests and microfluidic devices for rapid point-of-care-testing (POCT) of patient samples require human sampling procedures for collection of a patient sample at defined time points. The microfluidic sampling device is designed ultimately to be backwards compatible with existing clinical saline infusion protocols and function as a universal front-end blood sampling unit for the variety of microfluidic lab chips and POCT devices.

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