Point-of-care, portable microfluidic blood analyzer system
Date of this Version
2-9-2012Citation
Proc. SPIE 8251, Microfluidics, BioMEMS, and Medical Microsystems X, 82510C (February 9, 2012); doi:10.1117/12.909051
Abstract
Recent advances in MEMS technology have provided an opportunity to develop microfluidic devices with enormous potential for portable, point-of-care, low-cost medical diagnostic tools. Hand-held flow cytometers will soon be used in disease diagnosis and monitoring. Despite much interest in miniaturizing commercially available cytometers, they remain costly, bulky, and require expert operation. In this article, we report progress on the development of a battery-powered handheld blood analyzer that will quickly and automatically process a drop of whole human blood by real-time, on-chip magnetic separation of white blood cells (WBCs), fluorescence analysis of labeled WBC subsets, and counting a reproducible fraction of the red blood cells (RBCs) by light scattering. The whole blood (WB) analyzer is composed of a micro-mixer, a special branching/separation system, an optical detection system, and electronic readout circuitry. A droplet of un-processed blood is mixed with the reagents, i.e. magnetic beads and fluorescent stain in the micro-mixer. Valve-less sorting is achieved by magnetic deflection of magnetic microparticle-labeled WBC. LED excitation in combination with an avalanche photodiode (APD) detection system is used for counting fluorescent WBC subsets using several colors of immune-Qdots, while counting a reproducible fraction of red blood cells (RBC) is performed using a laser light scatting measurement with a photodiode. Optimized branching/channel width is achieved using Comsol Multi-Physics (TM) simulation. To accommodate full portability, all required power supplies (40v, +/-10V, and +3V) are provided via step-up voltage converters from one battery. A simple on-board lock-in amplifier is used to increase the sensitivity/resolution of the pulse counting circuitry.
Discipline(s)
Nanoscience and Nanotechnology
Link to Full Text
Comments
Teimour Maleki, Todd Fricke, JT Quesenberry, Paul Todd and James F. Leary "Point-of-care, portable microfluidic blood analyzer system", Proc. SPIE 8251, Microfluidics, BioMEMS, and Medical Microsystems X, 82510C (February 9, 2012)
Copyright 2012 Society of Photo Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.
http://dx.doi.org/10.1117/12.909051