ANTIMICROBIAL COMPOSITION, PARTICULARLY BACTERICIDAL, VIRUCIDAL, FUNGICIDAL AND MYCOBACTERIAL FOR THE CLEANING OF CONTAMINATED SURFACES AND ITS USE Technical Field

The present invention relates to an antimicrobial composition, particularly bactericidal, virucidal, fungicidal and mycobacterial for the cleaning of contaminated surfaces and to the use of the same. Background Art

The surfaces of objects and articles ranging from floors, ceilings, door panels, glass windows to, e.g., medical devices, systems, machinery, kitchen worktops, kitchen equipment, can all be contaminated or colonized by microorganisms such as viruses, bacteria, mold, fungi, and in fact, if left dirty, are almost always contaminated with microbes to some degree.

Protecting humans from health problems or even life-threatening diseases through contact with such contaminated surfaces is an unequal struggle, e.g., in the field of surgery, home environment, food production, health care, child care, meat processing, schools, public transport and toilets.

Known antimicrobial compositions such as, e.g., commercially available disinfectants, soaps, detergents and sanitizing agents used to fight against contamination of solutions and surfaces with pathogens such as viruses or bacteria are only partly effective in reducing or preventing contamination of any nature, whether viral, microbial, fungal or mycobacterial.

Unfortunately, such antimicrobial compositions commonly cause environmental and human health concerns associated with the use of disinfectants, soaps, detergents and sanitizers.

Common disinfectants and detergents contain compounds such as, e.g., chlorine, ozone, chlorine dioxide or chloramines which react with naturally occurring organic matter, with anthropogenic contaminants and other natural elements, leading to the formation of Disinfection Byproducts (DBPs). These DBPs may have negative or uncertain effects on the environment and human health.

A possible alternative is disinfectants which contain quaternary ammonium compounds (QACs). QACs do not cause DBP formation and are therefore safer to use with regard to human health.

However, QACs are highly toxic to numerous aquatic organisms, comprising fish, daphnids, algae, rotifers, and other utilized microorganisms, as well as to the environment and humans.

This means that frequent use of these compounds may lead to serious damage to the aquatic and environmental ecosystem.

Although QACs solve some of the health risk problems associated with DBPs, QACs cause other unacceptable consequences associated with their frequent use.

As a result of the aforementioned deficiencies, the search for improved or innovative antimicrobial compositions and disinfectants, soaps, detergents and sanitizing agents is a matter of continuous effort.

Improved or new antimicrobial compositions and disinfectants, soaps, detergents and sanitizing agents are more efficient, more effective and/or safer when considering the duration of prevention against contamination and/or when considering the degree of decontamination and/or when considering the risk to human health or to the environment.

Description of the Invention

A first object of the invention is to provide an antimicrobial composition, particularly bactericidal, virucidal, fungicidal and mycobacterial for the cleaning of contaminated surfaces and its use, with an improved antimicrobial activity against microbes such as viruses, bacteria, fungi and mycobacteria, without posing an unacceptable risk to the environment or human health.

A second object of the invention is to provide an antimicrobial composition, particularly bactericidal, virucidal, fungicidal and mycobacterial for the cleaning of contaminated surfaces, which has improved as far as killing microbes, preferably viruses, bacteria, fungi and mycobacteria is concerned, and/or the prevention of the microbial growth on a surface, which, in contrast to known state-of-the-art antimicrobial compositions, does not contain compounds which may cause adverse consequences for the environment and human health, and which is sufficiently effective at eliminating contamination.

Another object of the present invention is to devise an antimicrobial composition, particularly bactericidal, virucidal, fungicidal and mycobacterial for the cleaning of contaminated surfaces and its use which allows the mentioned drawbacks of the prior art to be overcome within a simple, rational, easy and effective to use as well as affordable solution.

The aforementioned objects are achieved by the present antimicrobial composition having the characteristics of claim 1.

Furthermore, the aforementioned objects are achieved by the present cleaning product having the characteristics of claim 8.

Finally, the aforementioned objects are achieved by the present use of the antimicrobial composition having the characteristics of claim 10.

Brief Description of the Drawings

Other characteristics and advantages of the present invention will become more apparent from the description of a preferred, but not exclusive, embodiment of an antimicrobial composition, the cleaning product containing it, and its use, illustrated by way of an indicative, yet non-limiting example, in the accompanying tables of drawings wherein:

Figures 1-3 are representative graphs of bactericidal efficacy tests and of the duration of the bactericidal action over time.

Embodiments of the Invention

In a first aspect, the present invention relates to an antimicrobial composition, particularly bactericidal, virucidal, fungicidal and mycobacterial for the cleaning of contaminated surfaces.

The term “antimicrobial activity” has its normal scientific meaning throughout the text, and here relates to the activity that kills or blocks the growth of microorganisms.

The term “carrier” as used herein has its normal scientific meaning throughout the text and here relates to anything in which or on which contaminants, such as microorganisms, i.e. microbes such as bacteria, may be present and/or grow.

Generally, such a carrier is an aqueous solution, a gas such as air, an object, or a surface such as the surface of an object, such as, e.g., the surface of a ceiling, wall, floor, table, kitchen worktop, machinery, etc.

The term “surface” has its normal scientific meaning throughout the text, and here relates to any part of an object that constitutes its outer layer, comprising the flat surfaces such as e.g. floors, ceilings, door panels, glass panes, etc., but also other objects such as, e.g., medical devices, systems, machinery, kitchen equipment, etc.

The term “contamination” as used herein relates to the undesirable presence of pathogens inside or on an object, in an aqueous solution or in a gas such as air.

The term “disinfectant” has its normal scientific meaning throughout the text, and herein relates to a biocidal antimicrobial agent or an antimicrobial or biocidal solution which is, e.g., applied to the surface of inanimate objects or to a gas such as air, or, in order to destroy living microorganisms on such objects or to prevent contamination of such objects by microbes such as bacteria, viruses, fungi and mycobacteria.

According to the invention, the composition comprises: one or more copper-based compounds; one or more surfactants; and an aqueous solution.

It is specified that within the scope of the present disclosure, the expression “one or more copper-based compounds” indicates that the composition may comprise a plurality of copper-based compounds, either belonging to the same chemical type or belonging to different chemical types.

Similarly, in the context of the present disclosure the expression “one or more surfactants” indicates that the composition may comprise a plurality of surfactants, either belonging to the same chemical type or belonging to different chemical types.

The one or more copper-based compounds are present in a concentration by weight, estimated with respect to the total weight of the composition, comprised between 0.0001% and 50%.

Preferably, the one or more copper-based compounds are present in a concentration by weight, estimated with respect to the total weight of the composition, comprised between 5% and 20%.

Advantageously, the one or more copper-based compounds are present in a concentration by weight, estimated with respect to the total weight of the composition, comprised between 10% and 15%.

In addition, each of the one or more copper-based compounds comprise a concentration by weight of copper metal, estimated with respect to the total weight of the one or more copper-based compounds, comprised between 0.0001% and 50%.

Preferably, the one or more copper-based compounds comprise copper sulfate. Advantageously, the one or more copper-based compounds comprise pentahydrate copper sulfate.

Furthermore, the one or more surfactants are present in a concentration by weight, estimated with respect to the total weight of the composition, comprised between 1% and 40%.

In detail, the composition according to the present invention comprises at least one surfactant present in a concentration by weight comprised between 10% and 20%.

According to a preferred embodiment of the composition according to the invention, the latter comprises a mixture of surfactants present in an overall concentration by weight comprised between 20% and 35%.

Preferably, the aforementioned surfactants are of the ionic and/or non-ionic type.

Additionally, the composition according to the invention comprises hydrochloric acid present in a concentration by weight, estimated with respect to the total weight of the composition, comprised between 0.5% and 15%.

Furthermore, the composition according to the invention comprises one or more chelating agents of the one or more copper-based compounds.

The presence of the aforementioned chelating agents is adapted to allow avoiding the precipitation of the one or more copper-based compounds inside the antimicrobial composition and, at the same time, to allow the maintenance thereof in solution.

In a second aspect, the present invention relates to a disinfectant product, comprising: a) the antimicrobial composition as described above; and b) a thinner, preferably water.

Preferably, the disinfectant product comprises the antimicrobial composition in a concentration by weight, estimated with respect to the total weight of the product, comprised between 0.01% and 5%.

In other words, the antimicrobial composition according to the present invention has a concentration comprised between 10 mL/L of water and 17 mL/L of water, preferably 15 mL/L of water.

Advantageously, the disinfectant product has a pH comprised between 0 and 14. Preferably, the disinfectant product has a pH comprised between 3 and 6.

The aforementioned acid pH allows, in combination with the chelating agents, chelating only a minimum percentage of copper ions, thus ensuring that the latter remain active and persistent on the treated surfaces.

Furthermore, it cannot be ruled out from the scope of the present disclosure that the disinfectant product comprises at least one of: one or more antifoaming agents or one or more pH adjusting agents.

Finally, in a third aspect, the present invention relates to the use of the antimicrobial composition in the decontamination of a surface contaminated by a microbe such as a bacterium, virus, or fungus, or a mycobacterium in which the antimicrobial composition is added to the aqueous solution at a concentration of at least 0.01% by weight of the antimicrobial composition based on the total weight of the aqueous solution.

In order to evaluate the bactericidal effectiveness of the disinfectant product according to the present invention, the following experimental protocol was carried out.

The aforementioned protocol was set up by employing the disinfectant product (PRODUCT) with three different concentrations of the antimicrobial composition (COMPOSITION) according to the present invention.

Specifically, the antimicrobial composition employed in the aforementioned experimental protocol comprises: pentahydrate copper sulfate present in a concentration by weight substantially equal to 13.5%; surfactants present in an overall concentration by weight substantially equal to 33.6%; hydrochloric acid present in a concentration by weight substantially equal to 8.9%; water present in a concentration by weight substantially equal to 43.2%.

The following concentrations of antimicrobial composition were tested at:

- 3 ml of COMPOSITION in 1 L of water;

- 5 ml of COMPOSITION in 1 L of water;

- 15 ml of COMPOSITION in 1 L of water.

The disinfectant product thus prepared was sprayed as follows: a surface (worktop) made of monolithic stoneware has been artificially contaminated by spraying with waste water (the same water and the same level of spraying will be used);

5-minute waiting time and subsequent passage with disposable paper (previously sterilized under UV) in order to uniform the level of surface contamination; pre- sanitization sampling with swabs (no. 3 plates by contact, to be representative) for research of Mesophilic Bacterial Charge and Enterobacteria (CBM); spraying with known solution of PRODUCT (starting with the most diluted);

5-minute waiting time and subsequent passage with disposable paper (previously sterilized under UV) in order to uniform the sanitization and remove any excess product; post-sanitization sampling with swabs (no. 3 plates by contact, to be representative) for research of Mesophilic Bacterial Charge and Enterobacteria (CBM); sanitization of worktop with alcohol and return to the beginning for a new contamination and new test (new concentration of PRODUCT);

5 Subsequently, a test was also carried out to verify the “coverage” of any residual product over time against exposure to ambient air.

The tests to verify the coverage over time were carried out as follows: three surfaces (worktop) made of monolithic stoneware in the laboratory were artificially contaminated as seen above by spraying with waste water0 (the same water and the same level of spraying was always used);

5-minute waiting time and subsequent passage with disposable paper (previously sterilized under UV) in order to uniform the level of surface contamination; pre- sanitization sampling with swabs by contact for research of Mesophilic5 Bacterial Charge and Enterobacteria (CBM); sequential spraying of the three zones with a known solution of PRODUCT (starting from the most diluted to the most concentrated) in order to have the three zones with three different degrees of sanitization;

5-minute waiting time and subsequent passage with disposable paper0 (previously sterilized under UV) in order to uniform the sanitization and remove any excess product, using new paper for each zone; air sampling by means of a dynamic sampler with orthogonal impact (SAS) for the determination of the bacterial charge present (at about 1 m above the surfaces being tested); 5 post-sanitization sampling after 1 hour, 3 hours, 6 hours with swabs (plates by contact) for research of Mesophilic Bacterial Charge and Enterobacteria (CBM);

Below and in the figures the results obtained are shown in Tables 1-4. 0

Table 1

Table 3

Table 4

From the observation of the tables (Table 1-4) and Figures 1-3 shown above, it is clear that the increasing dosage of the PRODUCT employed for the sanitization of surfaces (sprayed with a surface flow rate of 24 ml/m2) has shown a significant increasing effectiveness as the concentration used increases (3, 5, 15 ml/1 of PRODUCT).

As far as the verification of coverage over time is concerned, 1 hour after sanitization the values were significantly low, even with the most diluted concentration of 3 ml/1. This means that by leaving the product to act for a longer time than in phase 1 (in the latter case 1 hour), removals close to 100% are obtained even with much lower concentrations of PRODUCT.

It has in practice been ascertained that the described invention achieves the intended objects.

In particular, the fact is emphasized that the particular solution of employing pentahydrate copper sulfate as a source of free or available copper ions depending on the environmental conditions (e.g., high humidity), to allow the formation of a protective surface film of the surface onto which the antimicrobial composition or the disinfectant product is applied according to the present invention. In detail, the copper ions released in water, by means of ionic bonds, form the protective film having considerable effectiveness and duration over time compared to the currently known antimicrobial compositions and disinfectant products.