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. In one embodiment, an apparatus for plasma cleaning includes a hollow dielectric member having a first opening disposed at a first end of the hollow dielectric member and an electrode coupled to a central portion of an outer surface of the hollow dielectric member. A conductive member is coupled to the outer surface of the hollow dielectric member proximate the first end of the hollow dielectric member.
1 . Apparatus for plasma cleaning, comprising:
a hollow dielectric member having a first opening disposed at a first end of the hollow dielectric member;
an electrode coupled to a central portion of an outer surface of the hollow dielectric member; and
a conductive member coupled to the outer surface of the hollow dielectric member proximate the first end of the hollow dielectric member.
2 . The apparatus of claim 1 , wherein the conductive member further comprises an extension that protrudes along an inner surface of the hollow dielectric member.
3 . The apparatus of claim 2 , wherein a distance measured along a central axis of the hollow dielectric member and defined between a first end of the protruding extension of the conductive member and a proximal edge of the electrode is greater than or equal to zero.
4 . The apparatus of claim 1 , wherein the conductive member is grounded.
5 . The apparatus of claim 1 , further comprising:
a dielectric flange coupled to the outer surface of the hollow dielectric member and adjacent to the conductive member.
6 . The apparatus of claim 1 , further comprising:
at least a second hollow dielectric member having a first opening disposed at a first end of the second hollow dielectric member, and having an electrode coupled to a central portion of an outer surface of the second hollow dielectric member.
7 . The apparatus of claim 6 , wherein the hollow dielectric members are arranged in a substantially planar array and wherein a central axis of each of the hollow dielectric members are substantially parallel.
8 . The apparatus of claim 6 , wherein the hollow dielectric members are arranged in a mictrotiter plate format.
9 . The apparatus of claim 6 , wherein each of the electrodes are coupled together.
10 . The apparatus of claim 6 , further comprising:
a dielectric flange coupled to the outer surfaces of each of the hollow dielectric members and adjacent to the conductive member.
11 . The apparatus of claim 6 , wherein the conductive member substantially surrounds each of the first openings of the hollow dielectric members.
12 . The apparatus of claim 1 , wherein the hollow dielectric barrier member is cylindrical.
13 . The apparatus of claim 1 , wherein the hollow dielectric barrier member is a polygonal tube.
14 . The apparatus of claim 1 , further comprising:
a second opening formed through the hollow dielectric member proximate a second end of the hollow dielectric member opposite the first end.
15 . The apparatus of claim 14 , wherein the second opening is fluidly coupled to a negative pressure source adapted to draw plasma cleaning byproducts through the second opening.
16 . 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.
17 . 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.
18 . The apparatus of claim 1 , wherein a second end of the hollow dielectric member opposite the first end is closed.