Separating Plasma and Blood Cells by Dielectrophoresis in Microfluidic Chips

Abstract

In this paper, a dielectrophoretic (DEP) micro separator is studied for plasma-blood separation. DEP forces created by non-uniform electric fields are used as deflected forces to deplete blood cells from side walls at a given inlet flow rate ( Qin ). Then one can extract plasma through a microchannel on side wall at certain extraction flow rate ( Qp ). In this experiment, saline isotonic solution is chosen as dilute solution for whole blood. The minimum dilute ratio (whole blood: saline dilute) is found to be 1:3 for DEP to substantially deplete blood cells from side walls. Exraction of plasma from whole blood sample by DEP force is also investigated. Experimental results show blood cells do not enter side channel by DEP force at inlet flow rate Qin =0.5 μ1/ min when plasma extract flow rates is Qp ≤ 0.3 μ1/ min . By calculating pure plasma extraction volume fraction, the efficiency in current experiment can reach as high as 20% if dilute ratio 1:3 of whole blood sample is considered.

Benchtop Technologies for Circulating Tumor Cells Separation Based on Biophysical Properties

“…As a result, it might cause cells to experience nDEP most of the time and thus influence separation performance, thus influencing the cell separation performance as well as the purity output. Though Gascoyne et al [ 96 ] suggested that CTCs enrichment through blood dilution allows DEP devices to have optimal recovery, Leu and Liao [ 103 ] have reported that the actual extraction efficiency drops for 20% if the dilute ratio 1 : 3 of whole blood sample was conducted. Despite the use of nDEP that is able to levitate particles above the electrodes and thus protects vulnerable biological particles from high electric fields, RBC could also be irreversibly damaged as a means of cell rupturing if electric field much higher than 0.12 MV/m is applied [ 104 ].…”

High-throughput separation of cells by dielectrophoresis enhanced with 3D gradient AC electric field

“…Thus, the DEP is one of the most effective and widely used techniques not only for manipulating but also for separating, sorting, and identifying cells in microfluidic systems. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] However, significant technical challenges arise in applying DEP to clinical applications, where it is necessary to process extremely large numbers of cells with adequate separation at a sufficiently high throughput. It a) Author to whom correspondence should be addressed: stada@nda.ac.jp.…”

Computational Analysis of Enhanced Circulating Tumour Cell (CTC) Separation in a Microfluidic System with an Integrated Dielectrophoretic-Magnetophorectic (DEP-MAP) Technique

“…Additionally, the high conductivity of a blood suspension is reported to cause significant heating within a DEP device. This may lead to undesirable lysing of cells [26,27]. As first noted by Gascoyne et al [28], the integration of multiple separation forces enables a microfluidic device to precisely control the cell separation dynamics, and thus give rise to new modalities of separation.…”

“…Such a scenario is mainly caused by the high conductivity of blood [25]. This distinctive blood feature has resulted in cells experiencing negative DEP most of the time, and therefore influencing the separation performance of a DEP device (e.g., difficult to obtain a high purity output) [26]. Additionally, the high conductivity of a blood suspension is reported to cause significant heating within a DEP device.…”