SELF-DISINFECTING ULTRASOUND PROBE

Abstract

An ultrasound probe with antimicrobial surface activity includes a housing, wherein the housing has an antimicrobial compound present at an exterior surface of the probe housing in sufficient concentration to provide antimicrobial activity with microbes that contact the exterior surface of the ultrasound probe. A plurality of antimicrobial compounds may be present at the exterior surface of the probe housing in sufficient concentration to provide antimicrobial activity. The antimicrobial compound may be an additive to a polymeric material from which the probe housing is manufactured. The antimicrobial compound may be present in an antimicrobial coating disposed on the exterior surface of the probe housing. The antimicrobial activity may provide log reductions in gram+ and gram− bacteria after 24 hours in the range from 3 to 7.

Claims

1. An ultrasound probe with antimicrobial surface activity comprising a housing, wherein the housing comprises an antimicrobial compound, wherein the antimicrobial compound is present at an exterior surface of the probe housing in sufficient concentration to provide antimicrobial activity with microbes that contact the exterior surface of the ultrasound probe.

2. The ultrasound probe according to claim 1, wherein the antimicrobial compound is selected from hydrogen peroxide, zinc oxide, ionic zinc (Zn.sup.2+), chlorhexidine, silver (ionic), silver nanoparticles, triclosan, polyhexamethylene biguanide (PHMB), quaternary ammonium compounds, guanidine, guanidinium compounds, porphyrin, methylene blue, toluidine blue, and rose bengal.

3. The ultrasound probe according to claim 1, wherein the housing comprises a plurality of antimicrobial compounds.

4. The ultrasound probe according to claim 1, wherein the antimicrobial compound is ionic zinc (Zn.sup.2+).

5. The ultrasound probe according to claim 1, wherein the antimicrobial compound is selected from zinc oxide (ZnO), zinc oxide nanoparticles, and zinc oxide micron particles.

6. The ultrasound probe according to claim 1, wherein the antimicrobial compound is an additive to a polymeric material from which the probe housing is manufactured.

7. The ultrasound probe according to claim 6, wherein the antimicrobial compound is dispersed homogeneously throughout the polymeric material from which the probe housing is manufactured.

8. The ultrasound probe according to claim 6, wherein the antimicrobial compound is dispersed nonhomogeneously throughout the polymeric material from which the probe housing is manufactured, such that a relatively greater amount of the antimicrobial compound is present at the exterior surface compared to an interior of the probe housing.

9. The ultrasound probe according to claim 6, wherein the polymeric material from which the probe housing is manufactured is selected from polypropylene, polyethylene, polyvinylchloride, polyurethane, polysulfone, polyphenylsulfone, acrylonitrile butadiene styrene, polyethylene terephthalate, polyamide, polyarcrylates, polyvinyl acetates, polyimide, polyamideimide, polymethylmethacrylate, polyetherimide, polyetheretherketone, polyethersulfone, polycarbonate, and polyester.

10. The ultrasound probe according to claim 6, wherein the polymeric material from which the probe housing is manufactured is selected from polyphenylsulfone, polyurethane and polypropylene.

11. The ultrasound probe according to claim 6, further comprising an antimicrobial coating disposed on the exterior surface of the probe housing, wherein the antimicrobial coating comprises a second antimicrobial compound.

12. The ultrasound probe according to claim 11, wherein the second antimicrobial compound is selected from ionic zinc (Zn.sup.2+), chlorhexidine, copper, silver (ionic), triclosan, polyhexamethylene biguanide (PHMB), quaternary ammonium compounds, guanidine, and guanidinium compounds.

13. The ultrasound probe according to claim 11, wherein the coating is selected from a dip coating, a spray coating, an imbibe coating, and a hydrogel coating.

14. The ultrasound probe according to claim 1, wherein the antimicrobial compound is present in an antimicrobial coating disposed on the exterior surface of the probe housing.

15. The ultrasound probe according to claim 14, wherein the coating is selected from a dip coating, a spray coating, an imbibe coating, and a hydrogel coating.

16. The ultrasound probe according to claim 1, wherein the antimicrobial activity provides greater than 3 log reductions in gram+ and gram− bacteria after 24 hours.

17. The ultrasound probe according to claim 1, wherein the antimicrobial activity provides greater than 4 log reductions in gram+ and gram− bacteria after 24 hours.

18. The ultrasound probe according to claim 1, wherein the antimicrobial activity provides greater than 5 log reductions in gram+ and gram− bacteria after 24 hours.

19. The ultrasound probe according to claim 1, wherein the antimicrobial activity provides greater than 6 log reductions in gram+ and gram− bacteria after 24 hours.

20. The ultrasound probe according to claim 1, wherein the antimicrobial activity provides greater than 7 log reductions in gram+ and gram− bacteria after 24 hours.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0027] Example embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

[0028] FIG. 1 is a representation of an ultrasound probe.

[0029] FIG. 2 is a partial cross-sectional representation of an ultrasound probe housing.

[0030] FIG. 3 is a partial cross-sectional representation of an ultrasound probe housing having a coating.

DESCRIPTION OF EMBODIMENTS

[0031] The disclosure relates to an ultrasound probe with an exterior surface possessing antimicrobial efficacy. The ultrasound probe has a housing which may be impregnated and/or coated with one or more antimicrobial compounds to provide the exterior surface with antimicrobial functionality.

[0032] Referring to FIG. 1, in some embodiments an ultrasound probe 100 with an antimicrobial surface activity comprises a housing 110, wherein the housing comprises an antimicrobial compound. FIG. 2 shows a partial cross-sectional representations of the ultrasound probe housing 110 having antimicrobial surface activity. The ultrasound probe 100 has an exterior surface 120. One or more antimicrobial compounds are present at the exterior surface 120 in sufficient concentration to provide antimicrobial activity with microbes that contact the exterior surface 120 of the ultrasound probe 100.

[0033] In an embodiment, one or more antimicrobial compound additives are incorporated into the material from which the probe housing is manufactured. Non-limiting examples of suitable antimicrobial compounds include ionic zinc (Zn.sup.2+), silver nanoparticles, porphyrin, methylene blue, toluidine blue, and rose bengal.

[0034] The probe housing may comprise one or more polymeric materials. Probe housing polymeric materials include, but not limited to, polypropylene, polyethylene, polyvinylchloride, polyurethane, polysulfone, polyphenylsulfone, acrylonitrile butadiene styrene, polyethylene terephthalate, polyamide, polyarcrylates, polyvinyl acetates, polyimide, polyamideimide, polymethylmethacrylate, polyetherimide, polyetheretherketone, polyethersulfone, polycarbonate, and polyester.

[0035] One or more antimicrobial compounds can be incorporated directly into the ultrasound probe housing material by integrating them directly into the raw resin before molding or by integrating them into a modifier resin which is designed to compatibilize the active antimicrobial compound with the ultrasound probe's housing material.

[0036] The antimicrobial compound may be dispersed homogeneously throughout the polymeric material from which the probe housing is manufactured.

[0037] The antimicrobial compound may be dispersed nonhomogeneously throughout the polymeric material from which the probe housing is manufactured, such that a relatively greater amount of the antimicrobial compound is present at the exterior surface 120 compared to an interior 130 of the probe housing. In other words, a concentration of one or more antimicrobial compounds at the exterior surface 120 of the ultrasound probe housing 110 may be higher than a theoretical concentration based on uniform distribution of ingredients of the material from which the housing is fabricated.

[0038] More than one antimicrobial compound may be dispersed throughout the polymeric material from which the probe housing is manufactured. A plurality of antimicrobial compounds may provide a broader spectrum of antimicrobial activity.

[0039] FIG. 3 shows a partial cross-sectional representations of another embodiment of the ultrasound probe housing 110 having antimicrobial surface activity.

[0040] One or more antimicrobial compounds may be incorporated into a coating 140 on the ultrasound probe housing 110 such that the one or more antimicrobial compounds are present at the exterior surface 120 of the ultrasound probe in sufficient concentration to provide antimicrobial activity with microbes that contact the exterior surface 120 of the ultrasound probe 100.

[0041] Known coating technologies which incorporate the antimicrobial compound may be used. Examples of such coating technologies includes, but are not limited to, a dip coating, a spray coating, an imbibe coating, and a hydrogel coating. In some embodiments a primer chemistry may be used to improve coating adhesion.

[0042] Polyurethane is a coating matrix which may be used with dip coating and spray coating technologies. Non-limiting examples of solvents which may be used with polyurethane-based coatings include methanol, ethanol, isopropyl alcohol (IPA), dioxolane, methyl ethyl ketone (MEK), tetrahydrofuran (THF), and acetone. The coating solutions typically dissolve at temperatures in the range of 50° C. to 80° C. The dip coating and spray coating process is typically performed at room temperature. Examples of antimicrobial compounds which may be used in the dip coating and spray coating technologies include, but are not limited to, ionic zinc (Zn.sup.2+), chlorhexidine, copper, silver (ionic), triclosan, polyhexamethylene biguanide (PHMB), quaternary ammonium compounds, guanidine, and guanidinium compounds.

[0043] Imbibe coatings may be prepared by exposing a polymeric substrate to a solvent containing the antimicrobial compound. Typical solvents include, but are not limited to methanol, ethanol, isopropyl alcohol (IPA), dioxolane, methyl ethyl ketone (MEK), tetrahydrofuran (THF), and acetone. The imbibe coating process may be performed at a temperature in the range from room temperature to about 100° C. Examples of antimicrobial compounds which may be used in the imbibe coating include, but are not limited to, chlorhexidine, copper, silver (ionic), triclosan, polyhexamethylene biguanide (PHMB), quaternary ammonium compounds, guanidine, and guanidinium compounds.

[0044] A hydrogel is a known coating matrix used with dip coating and spray coating technologies. Non-limiting examples of hydrogels include polyvinyl alcohol, polyethylene glycol (PEG), and polyacrylate-based hydrogels. Non-limiting examples of solvents which may be used with hydrogel-based coatings include water, methanol, ethanol, and isopropyl alcohol (IPA). A pH/acid modifier may be included. The hydrogel coating solutions typically dissolve at temperatures in the range of 60° C. to 95° C. The dip coating and spray coating process is typically performed at room temperature. The hydrogel coating may be cured in formaldehyde. Examples of antimicrobial compounds which may be used in the hydrogel dip coating and spray coating technologies include, but are not limited to, ionic zinc (Zn′), chlorhexidine, copper, silver (ionic), triclosan, polyhexamethylene biguanide (PHMB), quaternary ammonium compounds, guanidine, and guanidinium compounds.

[0045] In some embodiments, a combination of one or more antimicrobial compound additives incorporated into the material from which the housing is fabricated, and one or more antimicrobial compounds incorporated into a coating on the surface of the ultrasound probe are utilized to provide self-disinfecting properties.

[0046] Regardless of whether the antimicrobial compound is present in a coating or an additive to the probe housing material or a combination of both coating and additive, one or more antimicrobial compounds are present at the exterior surface of the ultrasound probe housing in sufficient concentration to interact with microbes that contact with surface of the probe. This enhanced design covers portions of the ultrasound probe that may contact the patient and clinician. Upon contact, the one or more antimicrobial compounds exert their antimicrobial activity with their respective mechanisms. Furthermore, the antimicrobial compounds will not elute or leach from the device in any capacity. Thus, the disclosed self-disinfecting ultrasound probe will be inexhaustible in providing continuous sterilization of the probe's surface.

[0047] Antimicrobial compounds which may be used in disclosed ultrasound probe embodiments to provide antimicrobial activity include, but are not limited to, the antimicrobial compounds listed in Table 1, below.

TABLE-US-00001 TABLE 1 Antimicrobial Compounds Antimicrobial Compound Concentration Ranges Concentration In Silver (ionic) 1-20 wt. % Coating on product Silver (ionic) 1-20 wt. % Imbibe solution Chlorhexidine 1-20 wt. % Coating on product Chlorhexidine 1-20 wt. % Imbibe solution PHMB 1-20 wt. % Coating on product PHMB 1-20 wt. % Imbibe solution Ionic zinc (Zn.sup.2+) 0.009-6% Final product material Zinc oxide + H.sub.2O.sub.2 20 wt. % ± 10% Coating on product Guanidine 1-20 wt. % Coating on product Guanidine 1-20 wt. % Imbibe solution Guanidinium 1-20 wt. % Coating on product Guanidinium 1-20 wt. % Imbibe solution Triclosan 1-20 wt. % Coating on product Triclosan 1-20 wt. % Imbibe solution Quaternary ammonium 1-20 wt. % Coating on product compound Quaternary ammonium 1-20 wt. % Imbibe solution compound Porphyrin 0.05-5 wt. % Final product material Methylene blue 0.05-5 wt. % Final product material Toluidine blue 0.05-5 wt. % Final product material Rose bengal 0.05-5 wt. % Final product material Silver nanoparticle 5-50 ppm Final product material

EMBODIMENTS

[0048] Various embodiments are listed below. It will be understood that the embodiments listed below may be combined with all aspects and other embodiments in accordance with the scope of the invention.

[0049] Embodiment 1. An ultrasound probe with antimicrobial surface activity comprising a housing, wherein the housing comprises an antimicrobial compound, wherein the antimicrobial compound is present at an exterior surface of the probe housing in sufficient concentration to provide antimicrobial activity with microbes that contact the exterior surface of the ultrasound probe.

[0050] Embodiment 2. The ultrasound probe of embodiment 1, wherein the antimicrobial compound is selected from hydrogen peroxide, zinc oxide, ionic zinc (Zn.sup.2+), chlorhexidine, silver (ionic), silver nanoparticles, triclosan, polyhexamethylene biguanide (PHMB), quaternary ammonium compounds, guanidine, guanidinium, porphyrin, methylene blue, toluidine blue, and rose bengal.

[0051] Embodiment 3. The ultrasound probe of any preceding embodiment, wherein the housing comprises a plurality of antimicrobial compounds.

[0052] Embodiment 4. The ultrasound probe of any preceding embodiment, wherein the antimicrobial compound is ionic zinc (Zn.sup.2+).

[0053] Embodiment 5. The ultrasound probe of any preceding embodiment, wherein the antimicrobial compound is selected from zinc oxide (ZnO), zinc oxide nanoparticles, and zinc oxide micron particles.

[0054] Embodiment 6. The ultrasound probe of any preceding embodiment, wherein the antimicrobial compound is an additive to a polymeric material from which the probe housing is manufactured.

[0055] Embodiment 7. The ultrasound probe of embodiment 6, wherein the antimicrobial compound is dispersed homogeneously throughout the polymeric material from which the probe housing is manufactured.

[0056] Embodiment 8. The ultrasound probe of embodiment 6, wherein the antimicrobial compound is dispersed nonhomogeneously throughout the polymeric material from which the probe housing is manufactured, such that a relatively greater amount of the antimicrobial compound is present at the exterior surface compared to an interior of the probe housing.

[0057] Embodiment 9. The ultrasound probe of any of embodiments 6 through 8, wherein the polymeric material from which the probe housing is manufactured is selected from polypropylene, polyethylene, polyvinylchloride, polyurethane, polysulfone, polyphenylsulfone, acrylonitrile butadiene styrene, polyethylene terephthalate, polyamide, polyarcrylates, polyvinyl acetates, polyimide, polyamideimide, polymethylmethacrylate, polyetherimide, polyetheretherketone, polyethersulfone, polycarbonate, and polyester.

[0058] Embodiment 10. The ultrasound probe of any of embodiments 6 through 9, wherein the polymeric material from which the probe housing is manufactured is selected from polyphenylsulfone, polyurethane and polypropylene.

[0059] Embodiment 11. The ultrasound probe of any of embodiments 6 through 10, further comprising an antimicrobial coating disposed on the exterior surface of the probe housing, wherein the antimicrobial coating comprises a second antimicrobial compound.

[0060] Embodiment 12. The ultrasound probe of embodiment 11, wherein the second antimicrobial compound is selected from ionic zinc (Zn.sup.2+), chlorhexidine, silver (ionic), copper, triclosan, polyhexamethylene biguanide (PHMB), quaternary ammonium compounds, guanidine, and guanidinium compounds.

[0061] Embodiment 13. The ultrasound probe of any of embodiments 11 through 12, wherein the coating is selected from a dip coating, a spray coating, an imbibe coating, and a hydrogel coating.

[0062] Embodiment 14. The ultrasound probe of any of embodiments 1 through 5, wherein the antimicrobial compound is present in an antimicrobial coating disposed on the exterior surface of the probe housing.

[0063] Embodiment 15. The ultrasound probe according to claim 14, wherein the coating is selected from a dip coating, a spray coating, an imbibe coating, and a hydrogel coating.

[0064] Embodiment 16. The ultrasound probe of any preceding embodiment, wherein the antimicrobial activity provides greater than 3 log reductions in gram+ and gram− bacteria after 24 hours.

[0065] Embodiment 17. The ultrasound probe of any preceding embodiment, wherein the antimicrobial activity provides greater than 4 log reductions in gram+ and gram− bacteria after 24 hours.

[0066] Embodiment 18. The ultrasound probe of any preceding embodiment, wherein the antimicrobial activity provides greater than 5 log reductions in gram+ and gram− bacteria after 24 hours.

[0067] Embodiment 19. The ultrasound probe of any preceding embodiment, wherein the antimicrobial activity provides greater than 6 log reductions in gram+ and gram− bacteria after 24 hours.

[0068] Embodiment 20. The ultrasound probe of any preceding embodiment, wherein the antimicrobial activity provides greater than 7 log reductions in gram+ and gram− bacteria after 24 hours.

[0069] Other features and advantages of the disclosed invention are apparent from the different examples that follow. The examples below illustrate different aspects and embodiments of the present invention and how to make and practice them. The examples do not limit the claimed invention. Although methods and materials similar or equivalent to those described herein can be used in the practice of the present invention, suitable methods and materials are described below. Based on the present disclosure the skilled artisan can identify and employ other components and methodology useful for practicing the present invention.

EXAMPLES

Example 1

[0070] The antimicrobial surface activity of a polymeric material from which an ultrasound probe housing may be manufactured was tested. The polymeric material contained an antimicrobial compound comprising ionic zinc (Zn.sup.2+). The antimicrobial surface activity was verified according to one or more of the following standardized tests: ISO 22196, JIS Z 2801, ASTM E2149, ISO 20743, and FZ/T73023. The antimicrobial surface had an efficacy in the range of 3 Log reductions (99.9% reduction) to 7 Log reductions (99.99999%). The antimicrobial surface was effective against Staphylococcus aureus, Staphylococcus epidermidis, Clostridium difficile, Listeria, MRSA, Streptococcus mitis, Streptococcus sanguinis, a hemolytic streptococcus, Escherichia coli, Salmonella, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter cloacae, Legionella Pneumophila, Fusobacterium nucleatum, Eikenella corrodens, and Klebsiella pneumoniae.

Example 2

[0071] The antimicrobial surface activity of a substrate was tested. The substrate was coated with an aqueous dispersion comprising zinc oxide, a polymer, and hydrogen peroxide configured to provide a durable coating on the substrate.

[0072] Table 2 reports the antimicrobial surface activity at 24 and 72 hours against biofilms of Candida albicans, Staphylococcus aureus, and Pseudomonas aeruginosa.

TABLE-US-00002 TABLE 2 24 hour Biofilm 72 hour Biofilm Log Log Strains Reduction % Kill Reduction % Kill Candida albicans 0.22 39.18 0.39 58.90 Staphylococcus aureus 7.96 100.00 7.49 100.00 Pseudomonas aeruginosa 6.21 100.00 4.52 100.00

Example 3

[0073] The antimicrobial surface activity of a substrate was tested. The substrate was coated with a coating comprising guanidine or a coating comprising a porphyrin.

[0074] Table 3 reports the antimicrobial surface activity at 24 hours against biofilms of Candida albicans, Staphylococcus aureus, and Pseudomonas aeruginosa in two different media.

TABLE-US-00003 TABLE 3 24 hour Biofilm 24 hour Biofilm Guanidine antimicrobial Porphyrin antimicrobial compound compound Log Log Strains Reduction % Kill Reduction % Kill Candida albicans in Media 1 5.68 100.00 5.86 100.00 Candida albicans in Media 2 5.69 100.00 5.69 100.00 Staphylococcus aureus Media 1 7.75 100.00 7.07 100.00 Staphylococcus aureus Media 2 2.64 99.77 2.74 99.82 Pseudomonas aeruginosa Media 1 7.46 100.00 7.46 100.00 Pseudomonas aeruginosa Media 2 3.98 99.99 3.98 99.99

Example 4

[0075] The antimicrobial surface activity of a substrate was tested. The substrate was a 2.5 cm×2.5 cm polyurethane square coated with a coating comprising a quaternary ammonium compound.

[0076] Table 4 reports the antimicrobial surface activity at 24 and 72 hours against biofilms of Staphylococcus aureus, Klebsiella pneumoniae, Candida albicans, and Staphylococcus epidermidis in different media broths.

TABLE-US-00004 TABLE 4 Log Reduction 24 72 Strains Broths Hour Hour S. aureus 1/500 NB >5 >4.5 K. pneumoniae 1/500 NB >5 >5 C. albicans 1/500 NB >5 >5 S. epidermidis 20% NB in Butterfields phosphate buffer >5 >5 K. pneumoniae 10% NB in Butterfields phosphate buffer >5 >5 C. albicans 20% NB in Butterfields phosphate buffer >5 >5 Where “NB” is a neutralizing broth.

[0077] From the foregoing examples, antimicrobial studies have been performed on ultrasound probe surface materials to assess their antimicrobial efficacy. Greater than 4 log reductions and sometimes as high as 7-8 log reductions were found in gram+ and gram− bacteria at time points of 24 hours and 72 hours for certain ultrasound probe surface materials relative to a control ultrasound probe surface material. This suggests that the disclosed antimicrobial chemistries when integrated to the ultrasound probe will passively disinfect the probe without the requirement of additional workflow steps and capital equipment.

[0078] Reference throughout this specification to “one embodiment,” “certain embodiments,” “one or more embodiments” or “an embodiment” means that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Thus, the appearances of the phrases such as “in one or more embodiments,” “in certain embodiments,” “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily referring to the same embodiment of the invention. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.

[0079] Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It will be apparent to those skilled in the art that various modifications and variations can be made to the method and apparatus of the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention include modifications and variations that are within the scope of the appended claims and their equivalents.