APPARATUS FOR AND METHOD OF OBTAINING A BIOLOGICAL SAMPLE FROM A SURFACE

Abstract

An apparatus for obtaining a biological sample from an exposed surface of a human or animal body, the apparatus including a plurality of separate and porous ceramic particles for absorbing and adsorbing biological material from the exposed surface; and a permeable covering for containing the plurality of separate and porous ceramic particles, wherein the biological material having been absorbed and adsorbed by the plurality of separate and porous ceramic particles forms the biological sample.

Claims

1. An apparatus for obtaining a biological sample from an exposed surface of a human or animal body, the apparatus including a plurality of separate and porous ceramic particles for absorbing and adsorbing biological material from the exposed surface; and a permeable covering for containing the plurality of separate and porous ceramic particles, wherein the biological material having been absorbed and adsorbed by the plurality of separate and porous ceramic particles forms the biological sample.

2. The apparatus according to claim 1, wherein the plurality of separate and porous ceramic particles are inert and have a porosity of between 25% and 85%.

3. The apparatus according to claim 1, wherein the plurality of separate and porous ceramic particles have pores with a diameter of between 0.3 and 30 micrometres and wherein the pores are cellular in nature and are interconnected with one another by means of blow-holes.

4. The apparatus according to claim 1, wherein the plurality of separate and porous ceramic particles have a diameter of between 300 and 3000 micrometres.

5. The apparatus according to claim 1, wherein the plurality of separate and porous ceramic particles have a charged surface caused by ionic and electrostatic interaction, hydrogen bonding and charge-transfer interactions.

6. The apparatus according to claim 1, wherein the permeable covering is in the form of a sterile permeable and wettable sachet formed from an organic, non-woven material.

7. The apparatus according to claim 1, wherein the exposed surface is a wound of a human or animal and the biological material includes wound exudate containing any one or more selected from the group consisting of microorganisms, biomarkers, deoxyribonucleic acid (DNA), proteins, cellular molecules, endotoxins or combinations thereof, macrophages, neutrophils, fibroblasts, platelets, cytokines molecules including TNF-?, interleukins (ILs) and growth factors, including platelet-derived growth factor (PDGF), matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), IL-1, IL-6, and MMPs, proteases, protease inhibitors, and inflammatory markers, and the microorganisms include any one or more selected from the group consisting of bacteria, viruses, fungi and parasites.

8. A method of obtaining a biological sample from an exposed surface of a human or animal body, the method including the steps of providing an apparatus according to claim 1; and contacting the apparatus with the exposed surface to permit the plurality of separate and porous ceramic particles to absorb and adsorb biological material from the exposed surface, wherein the biological material having been absorbed and adsorbed by the plurality of separate and porous ceramic particles forms the biological sample.

9. The method according to claim 8, wherein the exposed surface is a wound of a human or animal and the biological material includes wound exudate containing any one or more selected from the group consisting of microorganisms, biomarkers, deoxyribonucleic acid (DNA), proteins, cellular molecules, endotoxins or combinations thereof, macrophages, neutrophils, fibroblasts, platelets, cytokines molecules including TNF-?, interleukins (ILs) and growth factors, including platelet-derived growth factor (PDGF), matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), IL-1, IL-6, and MMPs, proteases, protease inhibitors, and inflammatory markers, and the microorganisms include any one or more selected from the group consisting of bacteria, viruses, fungi and parasites.

10. (canceled)

11. A diagnostic method including the steps of providing the apparatus according to claim 1; contacting the apparatus with the exposed surface to permit the plurality of separate and porous ceramic particles to absorb and adsorb biological material from the exposed surface; and subjecting the apparatus to sonication to form a sonication fluid, the sonication step serving to disintegrate a biofilm of microorganisms present in the absorbed and adsorbed biological material so as to form a sonication fluid containing microorganisms.

12. The diagnostic method according to claim 11, wherein the sonication is performed at frequencies of 20 kilohertz.

13. The diagnostic method according to claim 11, which includes an additional step of using the sonication fluid to cultivate a bacterial culture or cultures for identifying bacterial strains present in the sonication fluid.

14. The diagnostic method according to claim 11, wherein the exposed surface is a wound of a human or animal and the biological material includes wound exudate containing any one or more selected from the group consisting of microorganisms, biomarkers, deoxyribonucleic acid (DNA), proteins, cellular molecules, endotoxins or combinations thereof, macrophages, neutrophils, fibroblasts, platelets, cytokines molecules including TNF-?, interleukins (ILs) and growth factors, including platelet-derived growth factor (PDGF), matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), IL-1, IL-6, and MMPs, proteases, protease inhibitors, and inflammatory markers, and the microorganisms include any one or more selected from the group consisting of bacteria, viruses, fungi and parasites.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0039] The plurality of separate and porous ceramic particles may be formed by a method including the steps of: [0040] (i) milling alumina (Al.sub.2O.sub.3) into a powder consisting of particles having a diameter of approximately 1 micrometre; [0041] (ii) adding a combustible substance to the powder; [0042] (iii) mixing the powder with water to form a paste or slurry; [0043] (iv) forming of particles from paste or slurry to separate particles having a diameter of between 300 and 3000 micrometres; and [0044] (v) heating the ceramic aggregate to a temperature of 1200? ? C., to form an inert microporous solid ceramic body having pore sizes of between 0.3 and 30 micrometres.

[0045] Each of the plurality of separate and porous ceramic particles has a diameter of between 30 and 3000 micrometres, are inert and have a porosity of between 25% and 85%.

[0046] The pores of the plurality of separate and porous ceramic particles are cellular in nature and have a diameter of between 0.3 and 30 micrometres. The pores are interconnected to one another by means of blow-holes, which form when the combustible substance escapes from the ceramic aggregate when the latter melts at or close to 1200? C.

[0047] A plurality of the separate and porous ceramic particles is encased in a liquid and gas permeable sachet to form an apparatus for obtaining a biological sample from an exposed surface of a human or animal body (e.g., a wound). The sachet is a sterile sachet and the separate and porous ceramic particles are packed loosely therein so as to allow air to pervade therethrough. The sachet is formed from an organic, non-woven material.

[0048] The plurality of separate and porous ceramic particles has a relatively large surface area and their micro-pores exhibit a significant capillary suction force.

[0049] In use, when the apparatus makes contact with the wound of the human or animal body, the plurality of separate and porous ceramic particles exert a capillary suction force on biological material present on the surface of the wound. The biological material is then absorbed, transported and stored in the micro-pores of the plurality of separate and porous ceramic particles. Since each separate and porous ceramic particle is in contact with surrounding particles of the same kind, biological material on the surface of the wound of the human or animal body migrates continuously between the particles to equalize the hydrostatic potential of all the separate and porous ceramic particles in the sachet. There is no driving force for the biological material to leave the micro-pores of the separate and porous ceramic particles. In this manner, a biological sample is obtained from the wound of the human or animal body.

[0050] As discussed above, each of the plurality of separate and porous ceramic particles is made from alumina (Al.sub.2O.sub.3). The surfaces of the plurality of alumina (Al.sub.2O.sub.3) particles are highly charged. The surfaces of the alumina (Al.sub.2O.sub.3) particles are relatively rough and have a wetting angle of 0?. Therefore, the alumina particles are easily wetted. The alumina (Al.sub.2O.sub.3) particles typically have a surface area of 0.5 m.sup.2 per gram of alumina (Al.sub.2O.sub.3). Each gram of alumina (Al.sub.2O.sub.3) comprises 3.5?10.sup.21 oxygen ions (O.sup.2?) and 2.4?10.sup.21 aluminium ions (Al.sup.3+), a fair portion of which are exposed to the surface of the particles.

[0051] It is known that every cell in a living organism contains an electrical charge defined as the difference between charged atoms on either side of the cell's membrane. A proton colloidal solid, on the other hand, may develop a surface charge due to the ionization of side-chain amino acid groups.

[0052] In use, when the plurality of separate and porous alumina particles comes into contact with biological material from the wound, the highly charged alumina surfaces (5.9?10.sup.21 ionic charges per gram) are continuously wetted by biological material. The surfaces of the plurality of separate and porous alumina particles are rough and ideal for adsorbing charged colloidal cells, microorganism, biomarkers, deoxyribonucleic acid (DNA) molecules, proteins, and endotoxins and the like to adhere thereto. Adhesion is caused by ionic and electrostatic interactions, hydrogen bonding and charge-transfer interactions. In this manner, strong adsorption takes place and a biological sample is obtained from the wound of the human or animal body.

[0053] The biological material includes wound exudate containing any one or more selected from the group consisting of microorganisms, biomarkers, deoxyribonucleic acid (DNA), proteins, cellular molecules, endotoxins or combinations thereof, macrophages, neutrophils, fibroblasts, platelets, cytokines molecules including TNF-?, interleukins (ILs) and growth factors, including platelet-derived growth factor (PDGF), matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), IL-1, IL-6, and MMPs, proteases, protease inhibitors, and inflammatory markers, and the microorganisms include any one or more selected from the group consisting of bacteria, viruses, fungi and parasites.

[0054] The apparatus for obtaining a biological sample from an exposed surface (e.g., a wound) of a human or animal body may include an adhesive dressing. When the apparatus is removed from the wound, the biological material siphoned off from the wound locates in the micro-pores as well as on the surfaces of the plurality of separate and porous ceramic particles. This biological material then forms the biological sample obtained from the wound.

[0055] The biological sample obtained from the wound is subjected to sonication to disintegrate a biofilm of microorganisms (e.g., bacteria) present in the biological sample and to form a sonication fluid containing microorganisms. Sonication is typically performed at frequencies of 20 kilohertz. The sonication fluid containing microorganisms is then used to cultivate microorganisms for identifying microorganisms present in the sonication fluid containing microorganisms. These microorganisms are typically bacteria and by cultivating the bacteria the different strains of bacteria present in the sonication fluid can be identified. This enables a healthcare practitioner to prescribe the correct treatment for an infected wound of a human or animal patient.

[0056] The sonication fluid can also be used to identify biomarkers which are indicative of the stage of wound healing. This will further inform a healthcare practitioner to prescribe the correct treatment for an infected wound of a human or animal patient.

[0057] It was found that the biological sample obtained from the wound could be analysed to predict wound healing and to guide wound care. In particular, analysing the levels of macrophages, neutrophils, fibroblasts, platelets, cytokines molecules including TNF-?, interleukins (ILs) and growth factors, including platelet-derived growth factor (PDGF), matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), IL-1, IL-6, and MMPs, proteases, protease inhibitors, and inflammatory markers, provide useful insight to wound care specialists on the status of the wound healing process and assist in predicting progress and prescribing the appropriate treatment regime.

[0058] It will be appreciated by those skilled in the art that the invention is not limited to the precise details as described herein and that many variations are possible without departing from the scope of the invention.

[0059] The description is presented by way of example only in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show more detail than is necessary for a fundamental understanding of the invention. The words which have been used herein are words of description and illustration, rather than words of limitation.