Ex-vivo multi-dimensional system for the separation and isolation of cells, vesicles, nanoparticles, and biomarkers
Devices and techniques are described that involve a combination of multidimensional electrokinetic, dielectrophoretic, electrophoretic and fluidic forces and effects for separating cells, nanovesicles, nanoparticulates and biomarkers (DNA, RNA, antibodies, proteins) in high conductance (ionic) strength biological samples and buffers. In disclosed embodiments, a combination of continuous and/or pulsed dielectrophoretic (DEP) forces, continuous and/or pulsed field DC electrophoretic forces, microelectrophoresis and controlled fluidics are utilized with arrays of electrodes. In particular, the use of chambered DEP devices and of a properly scaled relatively larger electrode array devices that combines fluid, electrophoretic and DEP forces enables both larger and/or clinically relevant volumes of blood, serum, plasma or other samples to be more directly, rapidly and efficiently analyzed. The invention enables the creation of “seamless” sample-to-answer diagnostic systems and devices. The devices and techniques described can also carry out the assisted self-assembly of molecules, polymers, nanocomponents and mesoscale entities into three dimensional higher order structures.
1. A process for separating elutable nanoscale analytes from larger entities in a high conductance sample, the process comprising:
(a) applying a high conductance biological sample of >100 mS/m comprising whole blood, serum, plasma, urine or saliva, to an alternating current (AC) electrokinetic device comprising a plurality of non-sputtered alternating current (AC) electrodes; and
(b) with an alternating current, selectively energizing the electrodes and establishing dielectrophoretic (DEP) high field and dielectrophoretic (DEP) low field regions in the high conductance sample, whereby AC electrokinetic effects separate elutable nanoscale analytes from larger entities in the high conductance sample by isolating elutable nanoscale analytes in the dielectrophoretic (DEP) high field region and isolating larger entities in the dielectrophoretic (DEP) low field region.
2. The process of claim 1 , wherein the alternating current has a frequency of less than 20 kHz.
3. The process of claim 1 , wherein the alternating current has a frequency of 10-50 kHz.
4. The process of claim 1 , wherein the nanoscale analytes: (1) are particles having a size of between 5 nm and 500 nm; (2) comprise (i) high molecular weight DNA, (ii) RNA, (iii) proteins, and/or (iv) cellular membrane; or (3) both.
5. The process of claim 1 , wherein the larger entities comprise cells and micron-sized particles.
6. The process of claim 1 , wherein the alternating current (AC) electrodes are solid platinum, palladium or gold materials.
7. The process of claim 1 , wherein the alternating current (AC) electrodes are wires or rods.
8. The process of claim 1 , further comprising removing the nanoscale analytes for further testing and storage.
9. The process of claim 1 , further comprising monitoring a separation process and analysis of separated biological components.
10. The process of claim 1 , further comprising selectively energizing the electrodes with direct current (DC) to establish DC electrophoretic fields, whereby DC electrokinetic effects provide for further separation of the elutable nanoscale analytes using DC electrophoresis.