Abstract:
A sanitization station including a fluid source and one or more plasma generators for generating non-thermal plasma is disclosed. One or more nozzles spray a mist or stream of fluid through plasma generated by the one or more plasma generators to activate the fluid. The fluid is then used to sterilize an object. Another sanitization station includes a chamber for holding a fluid and a plasma generator in fluid communication with the chamber for generating plasma. A circulating source moves the fluid in the chamber past plasma generated by the plasma generator to activate the fluid and one or more spray nozzles coat the surface of an object with fluid that is activated by plasma.

Description:
RELATED APPLICATIONS 
       [0001]    This non-provisional utility patent application claims priority to and the benefits of U.S. Provisional Patent Application Ser. No. 61/621,078 filed on Apr. 6, 2012 and entitled Sanitization Station Using Plasma Activated Fluid. This application is incorporated herein by reference in its entirety. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates generally to sanitizing systems and more particularly to sanitizing systems using plasma activated fluid for sanitization, such as, for example, pre-surgical hand and arm sterilization and pre-operative sterilization of surgical areas. 
       BACKGROUND OF THE INVENTION 
       [0003]    Surgeons, nurses and other technicians are required to sterilize their hands and arms prior to operating on patients. Generally, this process requires scrubbing one&#39;s hands and arms for a set period of time. 
       SUMMARY 
       [0004]    A sanitization station including a fluid source and one or more plasma generators for generating non-thermal plasma is disclosed. One or more nozzles spray a mist or stream of fluid through plasma generated by the one or more plasma generators to activate the fluid. The fluid is then used to sterilize an object. Another sanitization station includes a chamber for holding a fluid and a plasma generator in fluid communication with the chamber for generating plasma. A circulating source moves the fluid in the chamber past plasma generated by the plasma generator to activate the fluid and one or more spray nozzles coat the surface of an object with fluid that is activated by plasma. A sanitizing station having a housing having a transparent portion and one or more openings for placing one or more objects within the housing is also disclosed. The sanitizing station also includes a plasma generator for generating a non-thermal plasma and a fluid source connected to an atomizer. The atomizer is positioned to pass atomized fluid through non-thermal plasma generated by the plasma generator to activate the fluid. The activated fluid may be directed to the surface of the one or more objects located within the housing to sanitize the objects. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]    These and other features and advantages of the present invention will become better understood with regard to the following description and accompanying drawings in which: 
           [0006]      FIG. 1  is a sanitization station for sanitizing hands, arms and/or objects in accordance with one embodiment of the present invention; 
           [0007]      FIG. 2  illustrates another view of the embodiment of  FIG. 1 ; 
           [0008]      FIG. 3  illustrates a mister in accordance with one embodiment of the present invention; and 
           [0009]      FIG. 4  illustrates another embodiment of a sanitization station. 
       
    
    
     DETAILED DESCRIPTION 
       [0010]      FIGS. 1-2  illustrate a first exemplary embodiment of a sanitizing station  100 . Sanitizing station  100  may be used to sanitize objects, such as, for example, hands, arms, objects or equipment. In one embodiment (not shown), sanitizing station  100  may be configured on a larger scale to sanitize a large object, such as an entire body or large piece of equipment. Sanitizing station  100  includes a housing  102 . Housing  102  includes a top panel  104 . Preferably, top panel  104  is transparent so that a user may see into the sanitizing station. In one embodiment, top panel  104  is made of glass; optionally panel  104  may be made of Plexiglas® or a clear polymer. Housing  102  includes one or more apertures  105 . Apertures  105  may have sealing members  106  located therein. Sealing members  106  include slits  202 . Slits  202  allow access for a user to place an object, such as hands, arms or equipment within the interior of housing  102 . Located on the interior of housing  102  are one or more misters  108 . Misters  108  spray a fine mist of plasma activated water onto objects located within housing  102 . 
         [0011]      FIG. 3  illustrates an exemplary embodiment of a mister  108  for activating a fluid such as, for example, water, and spraying of plasma activated fluid  316 . Mister  108  includes a passage  309  for delivering a fluid such as, for example, water to mister  108 . In one embodiment, the fluid is distilled water. An atomizer  312  is located at the end of passage  309 . Atomizer  312  atomizes the fluid and directs it between electrodes  302  and  304 . In one embodiment, atomizing the fluid creates a large surface area around the small droplets. The large surface area allows for a quicker activation of the fluid. 
         [0012]    Electrode  302  is connected to a high voltage source  310  and is surrounded by a dielectric barrier  303 . Electrode  304  may also be at least partially surrounded by a dielectric barrier  305 . Dielectric barriers  303 ,  305  prevent arcing between electrode  302  and electrode  304 , which is connected to a ground. Dielectric barriers  303 ,  305  may include, for example, polymers, plastic, glass, ceramics or other known dielectric barriers. High voltage source  310  is connected to electrode  302  by cable  306 . High voltage source  310  may have an output of, for example, about 10 kV at between about 0.5 kHz and 500 kHz. In one embodiment, the distance between electrodes  302  and  304  is between about 2 mm and several centimeters. 
         [0013]    When electrode  302  is energized, non-thermal plasma is generated between the electrodes  302 ,  304  by ionizing the gas located between the electrodes  302 ,  304 . Fluid travels under pressure through conduit  309  and through atomizer  312 . Atomizer  312  may be, for example, a piezoelectric element, an atomizing nozzle or other mechanism that creates a mist or fine spray of fluid  316 . The mist or fine spray of fluid  316  passes through the plasma  314  and becomes plasma activated fluid, such as plasma activated water. The plasma activated fluid  316  is positively charged and is attracted to negatively charged, or grounded, objects such as the hands and arms  112  ( FIG. 1 ). Activated fluid  316  that over sprays objects located within housing  102  collects in the floor of housing  102  and flows out of the drain  110  to be disposed of or cleaned and recycled through sanitizing station  102 . 
         [0014]    Plasmas, or ionized gases, have one or more electrons that are not bound to an atom or molecule. Plasmas provide high concentrations of energetic and chemically active species and can operate far from thermodynamic equilibrium with high concentrations of active species and yet remain at a temperature that is substantially the same as room temperature. 
         [0015]    Non-thermal plasmas, or cold plasmas, contain free electrons. Unlike thermal plasmas, the temperature of the free electrons in non-thermal plasmas is greater than the temperature of the ions and heavy neutral atoms within the plasma. The energy from the free electrons may be transferred to additional plasma components creating additional ionization, excitation and/or disassociation. Fluid that is contacted with plasma becomes “activated” and is referred to herein as plasma activated fluid, and in some embodiments is plasma activated water. 
         [0016]    In some embodiments, plasmas may contain superoxide anions [O2.-], which react with H+ in acidic media to form hydroperoxy radicals, HOO., which is a powerful antimicrobial: [O2.-] +[H+]→[HOO.]. Other radical species may include OH. and NO.. Plasma activated water may contain concentrations of one or more of H 2 O 2 , nitrates, and nitrites. 
         [0017]    In addition, the properties of the fluid, such as water, may be altered prior to activation by plasma to increase or decrease concentration of radicals. For example, the pH of water may be adjusted to be acidic or basic. In one embodiment, the pH of the water is between about 2 and 3.5, in another is between about 2 and 3.5, and in yet another is about 2.7. The pH may be adjusted by, for example, adding nitric acid to the water prior to activation. In one embodiment, adjusting the pH levels adjusts the concentrations of radicals allowing for the adjustment of the efficacy of the plasma activated water to kill bacteria. 
         [0018]    In addition, the properties of the activated water may be adjusted during the activation process itself by altering the gas that is ionized. For example, the gas that is ionized may be normal air, nitrogen, N 2 , Oxygen, O 2 , He or combinations thereof 
         [0019]    In addition, in one embodiment, additives such as, for example, alcohol may be added to the water prior to activation. The alcohol may be used to increase the efficacy of the activated water for the killing of bacteria. In yet another embodiment, H 2 O 2  is used. Preferably, the concentration of H 2 O 2  is at about between 1-4%, and more preferably between about 1.5 and 3%. 
         [0020]    In one embodiment, co-additives may be added to the water that are capable of stabilizing the antimicrobially active species. Optionally, co-solvents such as low molecular weight alcohols may also be added to the water. 
         [0021]    In one embodiment, the water is activated under pressure, resulting in gas being dissolved in the activated water. The activated water may include additives such as, for example, wax that cause an activated foam to form when the liquid is released into normal atmospheric pressure. 
         [0022]      FIG. 4  illustrates a sanitizing station  400  in accordance with another embodiment of the present invention. Sanitization station  400  may be used in combination with the components described above with respect to sanitizing station  100  or may be used on its own. Sanitizing station  400  includes a chamber  401 . Chamber  401  may be formed by any suitable material such as, for example, polymer. Sanitization station  400  includes a pair of electrodes  402 ,  404  having dielectric barriers  403 ,  405 . Electrode  402  is connected to a high voltage source  410 . Chamber  401  contains a fluid such as, for example, water  420 . Other fluids such as H 2 O 2 , or mixtures of fluid, such as water and alcohol, may be used. Water  420  may be distilled water, tap water, filtered water, water with acidic properties, water with basic properties or water mixed with additives such as, for example, alcohol. Chamber  401  includes a fluid outlet passage  422  connected to a recirculating pump  424 . Recirculating pump  424  is connected to fluid passage  426  which is connected to atomizer  412 . Atomizer  412  may be a piezoelectric element, an atomizing nozzle or other mechanism that creates a fine mist or spray  416 . 
         [0023]    The fine mist or spray  416  passes through plasma generated by electrodes  402 ,  404  when electrode  402  is energized. After passing through the plasma, the fine mist or spray  416  is activated. The activated fine mist or spray  416  is located within chamber  401  and eventually mixes with the water  420  in chamber  401 . As the recirculating pump  424  continues to run, the concentration of activated water  420  increases. After a suitable time, enough of water  420  is activated so that the activated water  420  has acquired suitable properties to kill bacteria that it comes in contact with. Recirculating pump  424  may be turned off when the concentration of activated water is suitable to kill the bacteria it contacts, or optionally, recirculating pump  424  may run continuously. Allowing recirculating pump  424  to run continuously may allow for the use of a smaller plasma generator and reduce operating costs. 
         [0024]    Chamber  401  includes a second fluid outlet passage  428 . Fluid outlet passage  428  is connected to pump  430 , which is connected by fluid passage  432  to one or more spray nozzles  434 . Spray nozzles  434  may be piezoelectric elements, atomizing nozzles, misting nozzles, etc. When it is desired to sanitize objects such as, for example, hands, arms or equipment, pump  430  is turned on and activated water  420  is sprayed or misted onto the hands, arms and/or other objects. Chamber  401  may also include a water refill passage (not shown) to add additional water to the system. 
         [0025]    In one embodiment, chamber  401  is filled with air. Optionally, however, chamber  401  may be filled with other gasses such as, for example, N2, O2 or He; or a combination of one or more of these gases may be used. The gasses may be supplied under atmospheric pressure or under a pressure that is higher or lower than atmospheric pressure. A gas inlet passage (not shown) into chamber  401  may be provided. The use of different gasses may allow tuning of the activated water so that the activated water may have more efficacy killing all bacteria, or may be tuned to have a different efficacy at killing different types of bacteria. For example, it may be beneficial to kill certain bad bacteria while allowing some or all of certain good bacteria to survive. 
         [0026]    In one embodiment, a hand held nozzle is used to spray or mist activated fluid on body parts prior to surgery to sterilize the area around where an operation will occur. 
         [0027]    In one embodiment, the activated liquid mist has an electrostatic charge that when sprayed on an object having the opposite charge, or a neutral charge, the droplets in the mist rapidly provide uniform coverage over the surface of the object. 
         [0028]    In one embodiment (not shown) a closed chamber is used. A plasma gas is created in or directed to the closed chamber, and liquid in the closed container is activated. In one embodiment, an agitator agitates the liquid in the container. In another embodiment, plasma is bubbled up through a liquid to activate the liquid. In still yet another embodiment, an activated liquid is passed by or through a piezoelectric element located at the outlet of a tube to mist or atomize the activated liquid prior to spraying the activated liquid on an object. In one embodiment, a gliding arc plasma generator may be used. The spray of small droplets may pass through the plasma arc, and may require less dwell time to activate the liquid. 
         [0029]    In addition, other ingredients may be combined with the fluid to enhance the results of the activated fluid. For example, in one embodiment, a fluid containing a polymer is used. When exposed to the plasma, the polymer cross-links and forms a thin film on the surface of the object, such as skin, being treated. The thin film on the surface of the skin creates longer lasting antimicrobial activity. 
         [0030]    While the present invention has been illustrated by the description of embodiments thereof and while the embodiments have been described in considerable detail, it is not the intention of the applicants to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. For example, the sanitizing station  400  may be utilized in a shower, or portable shower system that may be set up to decontaminate persons or large objects on a site that has become contaminated by bacteria. Moreover, elements described with one embodiment may be readily adapted for use with other embodiments. Therefore, the invention, in its broader aspects, is not limited to the specific details, the representative apparatus and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the applicants&#39; general inventive concept.