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Title: Differential white cell count by centrifugal microfluidics.

Abstract

We present a method for counting white blood cells that is uniquely compatible with centrifugation based microfluidics. Blood is deposited on top of one or more layers of density media within a microfluidic disk. Spinning the disk causes the cell populations within whole blood to settle through the media, reaching an equilibrium based on the density of each cell type. Separation and fluorescence measurement of cell types stained with a DNA dye is demonstrated using this technique. The integrated signal from bands of fluorescent microspheres is shown to be proportional to their initial concentration in suspension. Among the current generation of medical diagnostics are devices based on the principle of centrifuging a CD sized disk functionalized with microfluidics. These portable 'lab on a disk' devices are capable of conducting multiple assays directly from a blood sample, embodied by platforms developed by Gyros, Samsung, and Abaxis. [1,2] However, no centrifugal platform to date includes a differential white blood cell count, which is an important metric complimentary to diagnostic assays. Measuring the differential white blood cell count (the relative fraction of granulocytes, lymphocytes, and monocytes) is a standard medical diagnostic technique useful for identifying sepsis, leukemia, AIDS, radiation exposure, and a hostmore » of other conditions that affect the immune system. Several methods exist for measuring the relative white blood cell count including flow cytometry, electrical impedance, and visual identification from a stained drop of blood under a microscope. However, none of these methods is easily incorporated into a centrifugal microfluidic diagnostic platform.« less

Authors:
; ;
Publication Date:
Research Org.:
Sandia National Laboratories
Sponsoring Org.:
USDOE
OSTI Identifier:
1021601
Report Number(s):
SAND2010-4901C
TRN: US201117%%195
DOE Contract Number:
AC04-94AL85000
Resource Type:
Conference
Resource Relation:
Conference: Proposed for presentation at the microTAS Conference held October 3-7, 2010 in Groningen, The Netherlands
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; BLOOD; BLOOD CELLS; CENTRIFUGATION; DIAGNOSTIC TECHNIQUES; DNA; DYES; FLUORESCENCE; IMPEDANCE; LEUKEMIA; LEUKOCYTES; LYMPHOCYTES; METRICS; MICROSPHERES; MONOCYTES; RADIATIONS; SORTING

Citation Formats

Sommer, Gregory Jon, Tentori, Augusto M., and Schaff, Ulrich Y.. Differential white cell count by centrifugal microfluidics.. United States: N. p., 2010. Web.
Sommer, Gregory Jon, Tentori, Augusto M., & Schaff, Ulrich Y.. Differential white cell count by centrifugal microfluidics.. United States.
Sommer, Gregory Jon, Tentori, Augusto M., and Schaff, Ulrich Y.. 2010. "Differential white cell count by centrifugal microfluidics.". United States. doi:.
@article{osti_1021601,
title = {Differential white cell count by centrifugal microfluidics.},
author = {Sommer, Gregory Jon and Tentori, Augusto M. and Schaff, Ulrich Y.},
abstractNote = {We present a method for counting white blood cells that is uniquely compatible with centrifugation based microfluidics. Blood is deposited on top of one or more layers of density media within a microfluidic disk. Spinning the disk causes the cell populations within whole blood to settle through the media, reaching an equilibrium based on the density of each cell type. Separation and fluorescence measurement of cell types stained with a DNA dye is demonstrated using this technique. The integrated signal from bands of fluorescent microspheres is shown to be proportional to their initial concentration in suspension. Among the current generation of medical diagnostics are devices based on the principle of centrifuging a CD sized disk functionalized with microfluidics. These portable 'lab on a disk' devices are capable of conducting multiple assays directly from a blood sample, embodied by platforms developed by Gyros, Samsung, and Abaxis. [1,2] However, no centrifugal platform to date includes a differential white blood cell count, which is an important metric complimentary to diagnostic assays. Measuring the differential white blood cell count (the relative fraction of granulocytes, lymphocytes, and monocytes) is a standard medical diagnostic technique useful for identifying sepsis, leukemia, AIDS, radiation exposure, and a host of other conditions that affect the immune system. Several methods exist for measuring the relative white blood cell count including flow cytometry, electrical impedance, and visual identification from a stained drop of blood under a microscope. However, none of these methods is easily incorporated into a centrifugal microfluidic diagnostic platform.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2010,
month = 7
}

Conference:
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