Plasma source and applications thereof

1. A low-power atmospheric pressure plasma source, comprising:

a ground electrode, provided on an external surface of a dielectric plasma confinement tube; and

a capillary electrode centered inside said ground electrode;

wherein a space, along the length of said confinement tube, between said capillary electrode and said ground electrode, defines a plasma-forming and plasma-confinement region, a plasma-forming gas being injected in said plasma-forming region; said capillary electrode being able to receive a source of reactive species for injection downstream of the plasma-forming and plasma-confinement region independently of the plasma-forming gas injected in said plasma-forming and plasma-confinement region and said source of reactive species is capable of producing reactive species from a variety of gas, said plasma source producing a plasma jet through a converging plasma exit.

2. The low-power atmospheric pressure plasma source of claim 1 , a converging nozzle of said plasma confinement tube forming said converging plasma exit.

3. The low-power atmospheric pressure plasma source of claim 1 , further comprising a source of reactive species.

4. The low-power atmospheric pressure plasma source of claim 3 , the source of reactive species being conveyed through one of: i) said capillary electrode, ii) air entrained in the plasma, and iii) the plasma-forming gas.

5. The low-power atmospheric pressure plasma source of claim 1 , the plasma-forming gas being one of He, Ar and N 2 .

6. The low-power atmospheric pressure plasma source of claim 1 , wherein the plasma is induced using a radio-frequency excitation.

7. The low-power atmospheric pressure plasma source of claim 6 , the radio-frequency excitation being generated by an amplitude-modulated waveform generator.

8. The low-power atmospheric pressure plasma source of claim 1 , operating at a power less than 5 W and voltage levels less than 600 V pk-to-0 .

9. The low-power atmospheric pressure plasma source of claim 1 , the plasma-forming gas being He at a few SLM, the plasma jet produced having a diameter of less than 500 μm and a length of about 2.5 mm a breakdown voltage being about 220 V pk-to-0 .

10. The low-power atmospheric pressure plasma source of claim 1 , a temperature of said plasma jet being compatible with bio-applications.

11. The low-power atmospheric pressure plasma source of claim 10 , the temperature of said plasma jet being less that 50° C. for a power level of about 1 W.

12. The low-power atmospheric pressure plasma source of claim 2 , further comprising a first injection line for injecting the plasma-forming gas in the space between said capillary electrode and said plasma confinement tube; and a second injection line for injecting the source of reactive gas in one of said capillary electrode and said space.

13. The low-power atmospheric pressure plasma source of claim 1 , said source being one of: i) handheld and ii) mounted on a robotic arm.

14. A plasma-assisted treatment system, comprising:

a low-power atmospheric pressure plasma source according to claim 2 ;

a radio frequency signal generator-amplifier-matching network system for powering the capillary electrode of said low-power atmospheric pressure plasma source; and

a gas delivery unit, which supplies gases to said low-power atmospheric pressure plasma source.

15. The low-power atmospheric pressure plasma source of claim 1 , used for at least one of: i) cell detachment, ii) surface functionalization and iii) cell permeabilization.

16. A method for cell modification using the low-power atmospheric pressure plasma source of claim 1 .