Dielectrophoretic Isolation and Detection of cfc-DNA Nanoparticulate Biomarkers and Virus from Blood

This study demonstrates the potential clinical relevance of this Biological Dynamics technologyor many future clinical diagnostic applications, including to virus and other pathogens detection. The authors showed rapid isolation and detection of SYBR Green stained cell-free DNA from 20 µL whole blood samples from Chronic Lymphocytic Leukemia (CLL) patients.

Overall the results of this study support the enormous potential of DEP as a “seamless sample-to-answer” technique for the rapid detection of cfc-DNA and nanoparticulate biomarkers directly from blood and other complex biological samples.

Dielectrophoretic (DEP) microarray devices allow important cellular nanoparticulate biomarkers and virus to be rapidly isolated, concentrated, and detected directly from clinical and biological samples.

A variety of submicron nanoparticulate entities including cell free circulating (cfc) DNA, mitochondria, and virus can be isolated into DEP high-field areas on microelectrodes, while blood cells and other micron-size entities become isolated into DEP low-field areas between the microelectrodes. The nanoparticulate entities are held in the DEP high-field areas while cells are washed away along with proteins and other small molecules that are not affected by the DEP electric fields. DEP carried out on 20 μL of whole blood obtained from chronic lymphocytic leukemia patients showed a considerable amount of SYBR Green stained DNA fluorescent material concentrated in the DEP high-field regions. Whole blood obtained from healthy individuals showed little or no fluorescent DNA materials in the DEP high-field regions. Fluorescent T7 bacteriophage virus could be isolated directly from blood samples, and fluorescently stained mitochondria could be isolated from biological buffer samples. 

Using newer DEP microarray devices, high-molecular-weight DNA could be isolated from serum and detected at levels as low as 8–16 ng/mL.


Publication Info: Electrophoresis. 2013 Apr; 34(7): 1076–1084. doi:  10.1002/elps.201200444