Patent Publication Number: US-2018036341-A1

Title: Method of using carbonized material to inhibit bacteria

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates generally to a method of using a carbonized material to inhibit bacteria, and more particularly to a method of using a material with an electrically conductive carbon-containing body to inhibit the growth of bacteria on wound. 
     2. Description of Related Art 
     People inadvertently suffer injuries (e.g., cutting injuries, abrasions, and burns) in daily lives. If the wound is not properly treated, the prognosis is usually poor, and the wound may be even infected. Especially, controlling of extensive burns is extremely difficult among the common injuries. Skin is a protective barrier over the body&#39;s surface, and once skin is seriously injured, it would cause the risk of dehydration and hypothermia. Moreover, if the wound is not well treated, the patient may have a severe infection a few days later, potentially leading to respiratory failure, multiple organ failures, or even death. In short, it is challenging for healthcare institutions to not only sustain burn patients, but also reconstruct the protective barrier (i.e., the skin) of patients. 
     If the depth of the burn extends deep into the reticular dermis, burn patients have to undergo skin autografting to prevent transplant rejection. However, skin substitutes (e.g., artificial skin or wound dressing) are needed for those patients who don&#39;t have enough healthy skin remained, or for extra protection over the treated wound. Currently, artificial skins with algin and silicone gauze are commonly used, wherein the former can keep the wound moist, and the latter is non-adhesive to the wound, and thus, these two kinds of artificial skins could both facilitate the healing. 
     However, the conventional skin substitutes mentioned above are all unable to effectively inhibit the growth of bacteria, and therefore, have to be replaced after being applied for a period of time. Consequently, it would consume a large amount of medical materials. Furthermore, replacing wound dressing frequently would be quite painful for burn patients. Therefore, seeking a better method for healing burn patients is a pressing issue. 
     BRIEF SUMMARY OF THE INVENTION 
     In view of the above, the primary objective of the present invention is to provide a method of using a carbonized material to cover a wound for inhibiting bacteria, which has a continuously and significantly antibiotic effect. 
     The present invention provides a method of using a carbonized material to inhibit bacterial, including providing the carbonized material which includes an electrically conductive carbon-containing body, exposing the carbonized material to a wet environment, and providing a direct current to the carbon-containing body, wherein the carbon-containing body is selected from the group consisting of carbon fiber fabric, graphene, and graphene oxide. Whereby, after the carbon-containing body is electrically energized by the direct current, hydrogen peroxide is synthesized form oxygen in the wet environment to inhibit bacterial growth. 
     Whereby, a small amount of hydrogen peroxide is synthesized by an electrochemical action to inhibit the growth of bacteria on the wound. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       The present invention will be best understood by referring to the following detailed description of some illustrative embodiments in conjunction with the accompanying drawings, in which 
         FIG. 1  is a schematic diagram of a first embodiment of the present invention, showing the carbonized material; 
         FIG. 2  is a partial schematic diagram of the carbonized material in  FIG. 1 , showing carbon fiber fabric includes a plurality of carbon fibers arranged in a crisscross pattern; 
         FIG. 3  is a flow chart of the method of using the carbonized material in  FIG. 1 ; and 
         FIG. 4  is a schematic diagram of using the carbonized material in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As shown in  FIG. 1 , the carbonized material  100  includes a carbon-containing body  10  and a plurality of silver particles  20  adhered to the carbon-containing body  10 . The carbon-containing body  10  is electrically conductive, and is at least one of carbon fiber fabric (CF), graphene, and graphene oxide (GO). The carbon fiber fabric has excellent adsorption characteristic and moisture retention. As illustrated in  FIG. 2 , the carbon fiber fabric includes a plurality of carbon fibers  12 , wherein a distance D between two adjacent carbon fibers  12  among the plurality of carbon fibers is between 0.2 nm and 0.25 nm; in the embodiment, the distance D is 0.23 nm. Practically, the carbon-containing body  10  can be the porous fiber fabric (activated carbon fiber fabric) disclosed in Taiwan patent 1334891 filed by the applicant of this invention. Moreover, the carbon-containing body  10  includes a multilayer structure which has a plurality of layers stacked; each of the layers is graphene or graphene oxide. 
     A ratio by weight of the silver particles  20  and the carbon-containing body  10  is between 0.5 to 5; in such range, the interplanar distance of the (111) plane of Ag in the carbonized material  100  is 0.23 nm, which is prone to attach to the carbon-containing body  10 . Additionally, the best ratio by weight of the silver particles  20  and the carbon-containing body  10  is 5, the preferred ratio is 1, and the next is 0.5. The silver particles  20  and the carbon-containing body  10  are mixed in liquid. In the embodiment, the ratio by weight of the silver particles  20  and the carbon-containing body  10  is 2. The carbonized material  100  can effectively adsorb wound exudate, blood, and bacteria when covering a wound; moreover, it can keep the wound wet. 
       FIG. 3  to  FIG. 4  shows the method of using the carbonized material  100  in inhibiting bacteria. First, expose the carbonized material  100  to a wet environment  1  which has oxygen. In practical, the wet environment  1  is a wound of an organism. In other words, the carbonized material  100  directly covers the wound. Next, provide a direct current to the carbon-containing body  10 , wherein the direct current is provided by a power supply  30  which provides a voltage of 1.75 N (1.75 multiples) volt, wherein N is a positive integer, and further satisfies: 
       1≦ N≦ 8;
 
     in the embodiment, N=2, and the power supply  30  is a battery providing a voltage of 3.5 volt. 
     After the electrically conductive carbon-containing body  10  is electrically energized, low concentration of hydrogen peroxide  2  is synthesized form oxygen in the wet environment  1  by an electrochemical action, and is released to the surface of the wound to inhibit the growth of bacteria on the wound. If the voltage provided form the power supply  30  is too high, the concentration of the hydrogen peroxide  2  would be too high, which may damage normal tissues of the organism. In contrast, if the voltage provided form the power supply  30  is too low, the concentration of the hydrogen peroxide  2  would be too low to effectively inhibit the growth of bacteria. 
     In conclusion, after the carbon-containing body  10  electrically energized, a small amount of hydrogen peroxide  2  would be released and subsequently inhibit the proliferation of bacteria on the wound, which preliminary inhibit bacteria. Yet a few remained bacteria growing with hydrogen peroxide  2  would be attracted by the carbonized material  100 , and further be impaled by the silver particles  20  thereof, which leads to the death of the bacteria. In this sense, the carbonized material  100  can significantly reduce the number of the bacteria on the wound by the abovementioned dual antibacterial effect, which effectively prevents wound infection. In addition, the multilayer structure in the carbon-containing body  10  consisting of graphene or graphene oxide could be barriers to bacteria, which prevents bacteria from proliferation and forming colonies on large wounds. 
     Additionally, moisture level in wounds is an important factor in wound healing. If a wound is not moisturizing enough, the prognosis is usually poor. With the carbon fiber fabric which has excellent moisture retention characteristic, the carbonized material  100  can effectively keep wounds wet. 
     With the characteristics mentioned above, the carbonized material  100  is suitable for large wounds, such as treatment for large burns. Furthermore, the power supply  30  could continuously provide electric current to the carbon-containing body  10  such that the carbonized material  100  could continuously release hydrogen peroxide  2  to the surface of the large wound, which enhances the inhibition of bacteria, and accelerates wound recovery. For burn patients, the carbonized material  100  in the invention is indeed helpful for wound healing. 
     It must be pointed out that the embodiments described above are only some preferred embodiments of the present invention. All equivalent methods which employ the concepts disclosed in this specification and the appended claims should fall within the scope of the present invention.