Atmospheric pressure non-thermal plasma device to clean and sterilize the surfaces of probes, cannulas, pin tools, pipettes and spray heads
The present invention relates to methods and apparatuses for the use of atmospheric pressure non-thermal plasma to clean and sterilize the surfaces of liquid handling devices.
1. Apparatus for plasma cleaning, comprising:
a plate having a conductive surface and an opposing dielectric surface, the plate having a plurality of openings extending through the conductive and dielectric surfaces;
a plurality of hollow dielectric members coupled at a first end to the dielectric surface of the plate and extending in a direction opposite the conductive surface, each of the plurality of hollow dielectric members having a first opening at the first end aligned with a respective one of the plurality of openings in the plate; and
an electrode coupled to a central portion of an outer surface of each of the hollow dielectric members.
2. The apparatus of claim 1 , wherein the conductive surface of the plate further comprises an extension that protrudes into at least one of the plurality of hollow dielectric members along an inner surface thereof.
3. The apparatus of claim 2 , wherein a distance measured along a central axis of the at least one hollow dielectric member and defined between a first end of the protruding extension of the conductive member and a proximate edge of the electrode is greater than or equal to zero.
4. The apparatus of claim 1 , wherein the conductive surface is grounded.
5. The apparatus of claim 1 , wherein a central axis of each of the plurality of hollow dielectric members are substantially parallel.
6. The apparatus of claim 1 , wherein the hollow dielectric member is cylindrical.
7. The apparatus of claim 1 , wherein the hollow dielectric member is a polygonal tube.
8. The apparatus of claim 1 , further comprising:
a second opening formed through at least one of the hollow dielectric members proximate a second end of the hollow dielectric member opposite the first end.
9. The apparatus of claim 8 , wherein the second opening is fluidly coupled to a negative pressure source adapted to draw plasma cleaning byproducts through the second opening.
10. The apparatus of claim 1 , wherein the plurality of hollow dielectric members are arranged in a microliter plate format.
11. The apparatus of claim 1 , further comprising a voltage source adapted to provide a voltage between about 5000 V to about 15000 V to the electrode.
12. The apparatus of claim 1 , further comprising a voltage source adapted to provide a voltage having a frequency between about 50 Hz and about 14 MHz to the electrode.
13. The apparatus of claim 1 , further comprising a closed end of at least one of the hollow dielectric members opposite the first end.