WO2023135352A1

WO2023135352A1 - Sanitising composition and use of same

Info

Publication number: WO2023135352A1
Application number: PCT/ES2023/070015
Authority: WO
Inventors: Javier MARTÍ SENDRA; David Ortiz de Zárate Díaz; Saturnino CASTILLO OÑATE
Original assignee: Universitat Politècnica De València
Priority date: 2022-01-12
Filing date: 2023-01-12
Publication date: 2023-07-20
Also published as: ES2922644A1; ES2922644B2

Abstract

The present invention describes sanitising compositions, preparation methods and the preferred uses thereof, which simultaneously allow hands and/or surfaces, objects, footwear, etc. to be sanitised and the quality of the sanitising process to be monitored by means of luminescence, in an immediate, safe, routine and economical manner. The compositions comprise a luminescent agent formed by a matrix and a luminescent reagent embedded in and/or joined to the matrix, thus improving the safety and efficiency thereof.

Description

DESCRIPTION

Sanitizing composition and use thereof

TECHNIQUE SECTOR

The present invention refers to the field of sanitizing products, and more particularly to those dedicated to sanitizing hands, footwear, objects and/or surfaces (without excluding other potential sanitizing uses), and its objective is, in particular, provide compositions, preparation methods and uses of sanitizing products that, in addition to breaking the chain of infection, allow the quality of the sanitization process to be monitored routinely and safely.

BACKGROUND OF THE INVENTION

Hands are one of the most important links in the chain of infection. There are numerous studies that show that the hands of patients and health workers are the main vector for spreading nosocomial infectious diseases (Pittet D. et al. Lancet. 2000, 356 (9238), 1307-12), although not the only one, since Both hands and footwear come into contact with objects and surfaces, spreading the pathogens they carry. This risk was evidenced in 1840 by the Hungarian physician Ignaz Semmelweis, who described it in his Theory of Germs (Codell Carter, K. Medical History 1985, 29, 33-53) to explain diseases, and who proposed an easy solution to mitigate it: correct hand disinfection.

Currently, to carry out correct hand hygiene, running water, antiseptic soap and an adequate washing and drying process are usually used.

However, this type of cleaning has several disadvantages (Harbarth S. Clin Infect Dis. 2000 Jun, 30(6), 990-1): (1) Sometimes it is not feasible to have the necessary infrastructures (running water and/or drying) to carry out that correct hand hygiene; (2) Compliance with the recommendations for handwashing with running water by healthcare personnel remains unacceptably low (between 10 and 50%) (Boyce JM. Ann Intern Med 1999, 130, 153-5), due to because the average hand washing time (8-20 seconds) is insufficient for most hand sanitizing agents to be fully effective, and that a a longer time (40-80 seconds) would be prohibitive, given the necessary disinfection frequency (a minimum of 20 times per hour in the ICU, for example).

To solve all these disadvantages, hand sanitizing products emerged, an excellent alternative to conventional hand washing, since it allows sanitizing to be carried out at any time and place, without depending on the existence of running water and drying infrastructures. . The main component of hand sanitizing products is alcohol, since as early as 1875 Leonid Bucholz demonstrated the excellent antiseptic properties of alcohol, capable of eliminating 99.9% of germs.

Although there is no evidence, nor is there any registered patent (despite the efforts of numerous organizations to find them), the origin of hydroalcoholic gel seems to date back to 1966, when Lupe Hernández, a nursing student from Bakersfield (California, United States), invented it to keep their hands properly sanitized, even in areas where there was no running water.

The use of hydroalcoholic gel remained mainly restricted to hospital use until the Influenza A epidemic in 2009, when hydroalcoholic gel became a truly mass commercial product.

And the global pandemic of the SARS-CoV-2 coronavirus, which paralyzed the entire world in 2020, once again revealed that the best measure to prevent not only COVID-19 but also many other infectious diseases (nosocomial or not) is the correct hand washing with hydroalcoholic gel (together with the use of masks and social distancing), adopting this measure mandatorily at the entrance of hospitals, health centers, large surfaces and public or private establishments, since the beginning of the pandemic.

The Spanish Agency for Medicines and Health Products (AEMPS) currently distinguishes between cosmetic gels and biocides, the latter used to sanitize healthy skin from pathogens.

The composition and use of disinfectant gels is regulated by Article 3 of the

Regulation (EU) 528/2012 (BPR) (https://www.boe.es/doue/2012/167/L00001- 00123.pdf) regarding the use and commercialization of biocides, in which its purpose is defined, which will be to "destroy, counteract or neutralize any harmful organism, or prevent its action or exert a control effect of another type on it, for any means other than a mere physical or mechanical action”.

The European Cosmetic Product Notification Portal (CPNP), in order to guide manufacturing companies, published a list of components and their maximum amounts: Ethanol or isopropanol: 70%; Emollients, humectants: 20%; Other ingredients (vitamins, plant extracts): 10%; Anionic, amphoteric and nonionic emulsifiers and surfactants: 6%; Thickeners: 5%; Preservatives and antimicrobials: 3.5%; Dyes: 1%; Perfume: 1%; Water: csp. Instead, the General Council of Pharmaceutical Colleges presented a simpler formulation: Ethanol 96°/absolute: 70-80%; Glycerin: 2-10%; Gelling agent: up to 3%, depending on the chosen component; Water: csp.

Notwithstanding all of the above, for hand hygiene to be truly effective, it is of vital importance to ensure the quality of the technique used, as concluded by several studies (Babeluk R, Jutz S, Mertlitz S, Matiasek J, Klaus C, Aiello A, et al. PLoS One 2014 Nov 7, 9(11): e111969), which show that 89% of people who sanitize their hands with hydroalcoholic gel leave some part uncleaned (generally thumbs and fingertips). Taylor, L.J. Nursing Times 1978 Jan 12, 74(2), 54-5).

In order to improve these results, a 6-step procedure was developed that forms the basis of the European standard EN 1500 that regulates the validation of the efficiency of sanitizing gels, created in 1997 and later updated in 2013 (EN 1500. Chemical disinfectants and antiseptics. Hygienic hand rub. Test method and requirements (phase 2/step 2). Brussels: European Committee for Standardization. 1997 and 2013).

The quality of the washing can be determined by microbiological analysis of the surface of the hands, and although it is a very exact and precise technique, its long response time makes it unfeasible for some applications (such as, for example, monitoring the correct hygiene of each of the people who access a hospital or establishment), in addition to the fact that it does not make it possible to distinguish whether there are clean or dirty areas, unless samples are taken from different areas of the hands. Exclusively as an educational measure, in the health field, hand sanitization training gels are used for professionals such as Visirub, Schülke Optics, Braun Fluo Rub, GloGerm etc., which demonstrate with UV light the areas of the hands that have been correctly washed with a fluorescent cream and those that do not. They are perfect tools to improve the washing technique, but they are not useful for routine use as disinfectants for several reasons (which may or may not occur simultaneously):

1 . They are not biocidal gels, so they do not fulfill the task of disinfecting hands.

2. The manufacturers of all these products recommend not using them routinely for hand disinfection (probably due to the presence of free fluorescent agents in their composition, generally toxic in high doses such as those necessary to monitor the quality of hand hygiene, which make it in unsafe).

There are previous patents that describe disinfectant solutions that change color or physical properties depending on the time elapsed since they were dispensed (for example, WO9629047, WO9709957), but they do not allow monitoring the quality of the cleaning process.

Other previous patents (for example, U.S. Patent No. 5,900,067 and 6,524,390) incorporate a fluorescent agent into the sanitizer and examine hands after washing and rinsing with water to verify that no soap residue remains, but this also does not allow monitoring of the quality of the sanitizer. cleaning process, in addition to the fact that introducing the free fluorescent agent, which is generally toxic, would make its routine use unadvisable.

Another previous patent (WG2008/118143A2) describes the formulation of a hand cleaning agent containing a fluorescent or phosphorescent agent and a binder. On vigorous hand rubbing, the aggregates dissociate releasing the fluorescent or phosphorescent agent, allowing the quality of handwashing to be monitored or judged based on the intensity of the fluorescence or phosphorescence. Therefore, this patent, which raises a very interesting theoretical concept, completely forgets the crucial aspect of safety, since fluorescent or phosphorescent agents are usually toxic and should not come into direct contact with the skin, let alone less in the amounts needed to monitor proper hand hygiene, and even less if you must routinely clean your hands.

Another previous patent (WO98/21569) describes a soap characterized by the presence of powdered yttrium oxide in its formulation, which gives it the ability to phosphoresce, in order to ensure the correct distribution of the cleaning product on the surface to be sanitized. . This patent presents two problems: the first and most important, safety (due to the cyto- and genotoxicity of yttrium oxide (Selvaraj V, Bodapati S, Murray E, et al. Int J Nanomedicine 2014, 9, 1379-1391) that it must be treated for all purposes as a heavy metal), and the second and much less important, that the product will phosphoresce for a while, so if it were applied to the hands of the users, they would probably perceive the experience as negative , and they could reject the use of the product.

Therefore, there is currently no solution to guarantee correct hand washing immediately, routinely, safely and economically.

EXPLANATION OF THE INVENTION

In order to improve prevention strategies against COVID-19 and other coexisting or future infectious diseases (nosocomial or not), compositions, preparation methods and preferred uses of new sanitizing products are described that will allow the simultaneous sanitization of hands, objects , surfaces, footwear, etc. and the monitoring of the quality of the sanitation process immediately, routinely, safely and economically. By way of examples, these new sanitizing products would be widely applicable in hospitals, health centers, public buildings, department stores, and other establishments, to guarantee that both professionals and visitors access safely, and even to monitor proper sanitation. of surfaces.

Then, in a first aspect, the present invention refers to a sanitizing composition that is characterized by comprising a luminescent agent, where said agent comprises:

-a luminescent reagent in an amount between 0.1 and 10% by weight with respect to the total weight of the luminescent agent and - a polymeric and/or inorganic matrix in an amount between 90 and 99.9% by weight with respect to the total weight of the luminescent agent, and where the luminescent reagent is embedded and/or attached to the matrix.

As used herein, the term "embedded" means enclosed, surrounded, or enveloped by the matrix, in whole or in part.

In the event that the luminescent reagent is attached to the matrix, the union between them can be by ionic or covalent bonding, or by intermolecular forces, such as Van der Waals forces, hydrogen bonds, etc. Preferably, the link between the luminescent reagent and the matrix is by covalent bonding. The luminescent reagent can be attached directly to the matrix by covalent bonding or through a linking group that acts as a bridge between said reagent and the matrix. By way of example, the linking group can be an organosilane or any chemical group that can simultaneously form a covalent bond with the luminescent reagent and with the matrix.

According to the present invention, "sanitizing composition" or "sanitizing composition" refers to a composition with detersive capacity and/or biocidal character, that is, capable of destroying, counteracting or neutralizing any harmful organism, or preventing its action, or exert a controlling effect of another kind on it, by any means other than a mere physical or mechanical action. For example, some sanitizing compositions could be a hydroalcoholic gel, a product for cleaning objects and/or surfaces, and a product for cleaning shoe soles, among other possibilities.

According to the present invention, the term "luminescent reagent" refers to a compound that has the ability to emit light radiation when activated by a stimulus (such as a source of electromagnetic radiation, a change in temperature or pressure, a chemical reaction, etc. .). Thus, the generic term "luminescent" includes the terms chemiluminescent, crystalloluminescent, electroluminescent, mechanoluminescent, photoluminescent, radioluminescent, and/or thermoluminescent.

According to the present invention, the term "matrix" refers to a compound of polymeric or inorganic nature, dense or porous, capable of embedding and/or bind to the luminescent reagent with 3 fundamental objectives: 1) make the luminescent reagent inert (they are generally soluble and present some toxicity, at least in a certain dose, and by embedding them in a more biocompatible solid matrix, their solubilization is prevented and their solubilization is limited). its ability to interact with the human body); 2) prevent the luminescent reagent from permeating into the human body through the skin (by being embedded and/or bound to a solid matrix of a certain size, its ability to permeate through the different layers of the skin is considerably limited ), and 3) improve the efficiency and stability of its luminescence (a matrix with a high refractive index can enhance the luminescence of the free luminescent reagent by diffractive effects, in addition to protecting it from decay).

The term "luminescent agent" refers to the set formed by the luminescent reagent and the matrix, either one embedded in the other, or joined together.

The characteristics of the luminescent agent make it safe and efficient. Therefore, the sanitizing composition that contains it will also be efficient and safe.

In accordance with the present invention and the nature of the luminescent agent described, the term "safe" refers to both a luminescent agent and a sanitizing composition that can be used with complete safety by the user, regardless of whether the composition is applied to objects/surfaces, or is for topical application. This is due to the fact that the luminescent reagent, generally toxic in solution (at a certain dose), is in this case embedded and/or bound to an inert matrix that also limits its skin permeability.

In accordance with the present invention and the nature of the luminescent agent described, the term "efficient" refers to the ability of both the luminescent agent and the sanitizing composition made from it, to generate luminescence, an efficiency that can be increased by the appropriate selection of a diffractive matrix.

In a preferred embodiment, the amount of luminescent reagent in the luminescent agent is between 0.1-5% by weight, and more preferably, between 0.1-1% by weight.

In another preferred embodiment, the luminescent reagent is a fluorescent reagent selected from: fluorescein, quinine, rhodamine, cresyl violet, cyanines, tryptophan, POPOP (1,4-Bis(5-phenyl-2-oxazolyl)benzene), tyrosine, quantum dots (QDs), conversion nanoparticles (upconverting nanoparticles or nanoparticles capable of absorbing two photons of relatively low energy, and emitting a higher energy photon, such as NaYbF ₄ :Tm,Er,Ho, LiYF4:Er etc.), metallic nanoparticles, preferably Au and Ag, and Li, Y or Ge oxides doped with Eu ³⁺ .

Conversion nanoparticles and metal nanoparticles mentioned in this paragraph refer to nanoparticles with a size generally between 1 and 100 nm.

The luminescent reagents of an organic nature (fluorescein, quinine, rhodamine, cresyl violet, cyanines, tryptophan, POPOP, tyrosine) can be in the form of their derivatives such as their salts and isothiocyanates, for example, fluorescein isothiocyanate.

Quantum dots (QDs) are generally semiconductor nanostructures, although they can also be made of C or Si, which, thanks to their small size (generally between 2 and 10 nm), are capable of confining the movement of electrons in the cell. conduction band and valence band gaps, which allows them to re-emit absorbed light at very specific wavelengths that depend on the size of the nanostructure.

In a more preferred embodiment, the luminescent agent is fluorescein or quinine, more preferably fluorescein.

For the application of the sanitizing product on the hands, the use of phosphorescent reagents is preferably ruled out, since the phosphorescence of the hands once the monitoring process has concluded can generate rejection in the users.

In a preferred embodiment, the amount of matrix in the luminescent agent is between 95 and 99.9% by weight, and more preferably between 99 and 99.9% by weight.

In a preferred embodiment, the matrix is inorganic in nature, more preferably ceramic, and comprises or consists of oxides of metallic elements or oxides of metalloid elements (the surface of said oxides can also be modified to modulate their reactivity) and even mixed oxides of said elements. More preferably, the matrix is an oxide of an element selected from: Si, Ti, Zr, Al and Zn. More preferably, the matrix comprises SiO2 and/or TIO2, porous or not.

Preferably, the luminescent agent, which is in the form of particles or aggregates of particles, has a particle or aggregate size greater than 200 nm, which ensures (by analogy with TIO? nanoparticles (NPs) used in the field of cosmetics) that both the luminescent agent itself and the sanitizing product derived from it will present practically zero skin permeability, which implies the complete dermatological safety of the composition. Skin permeability is established according to current regulations: test n° 428 of the OECD, “Skin absorption: in vitro method”.

In a preferred embodiment, the luminescent agent is in the form of particles with a size between 400 and 500 nm. The particle size was determined by scanning electron microscopy (SEM).

In another preferred embodiment, the luminescent agent is in the form of particles with a size between 800 and 1000 nm.

In another preferred embodiment, the luminescent agent is in the form of particle aggregates, where the aggregates are between 200 and 1000 nm in size.

In a preferred embodiment, the luminescent agent is present in a percentage by weight of between 1 and 30% in the sanitizing composition, more preferably, between 1 and 10%.

The sanitizing composition may also contain other products usually present in this type of composition such as: solvents, emulsifiers, antioxidants, stabilizers, moisturizers, odorizers, thickeners, surfactants, pH regulators, neutralizers, preservatives, germicides, bactericides, virucides, fungicides, emollients, moisturizers, preservatives, skin protectors, natural extracts, etc., without excluding other types of agents of cosmetic, pharmaceutical, or sanitizing interest.

In a preferred embodiment, the sanitizing composition is a hydroalcoholic gel, preferably with a minimum content of 70% by weight in ethanol and/or isopropanol. In a preferred embodiment, the sanitizing composition is a hydroalcoholic gel, with a minimum content of 70% by volume in ethanol and/or isopropanol.

In a more preferred embodiment, the sanitizing composition is a hydroalcoholic gel, preferably with a minimum content of 70% by weight or volume in ethanol or isopropanol, comprising between 1-30%, more preferably between 1 and 10% by weight, of a luminescent agent as defined above and a dispersing agent, preferably with a content of 0-10%.

Dispersing or dispersing agents are additives that allow or stabilize the optimum mixture of at least two substances, normally immiscible or slightly miscible. Examples of dispersing agents that can be used are ionic and nonionic surfactants, and among the latter, ethoxylated or propoxylated fatty alcohols, sorbitan esters, alkyl polyglucosides, alkanolamides, glycerol esters, and preferably glycerin or simple glycols (ethylene glycol, propylene glycol, ..).

Likewise, it is possible to introduce other components of interest for the formulation of hydroalcoholic gels, such as solvents, emulsifiers, antioxidants, stabilizers, moisturizers, odorants, thickeners, surfactants, pH regulators, neutralizers, preservatives, germicides, bactericides, virucides, etc. fungicides, emollients, moisturizers, preservatives, skin protectors, natural extracts, etc., without excluding other types of agents of cosmetic, pharmaceutical, or sanitizing interest.

In another more preferred embodiment, the sanitizing composition is a conventional cleaning product for cleaning any surface. By way of example, the cleaning product can refer to a product for cleaning floors, walls or any other surface or for cleaning shoes, including the sole thereof.

In a more preferred embodiment, the conventional cleaning product comprises at least one of the following components or a mixture thereof in a minimum percentage of 70% by weight with respect to the weight of the cleaning product: ionic and nonionic surfactants, quaternary ammonium salts , chlorhexidine, hexetidine, phenolic compounds, parabens, organic or inorganic acids, triclosan, cetylpyridinium salts, hydrogen peroxide and sodium hypochlorite, among others and comprises between 1-30%, plus preferably between 1 and 10% by weight, of a luminescent agent as defined above. The conventional cleaning product may or may not comprise a dispersant in a proportion between 0 and 10% by weight.

The sanitizing composition is safe, efficient and allows not only to sanitize objects, surfaces, footwear, etc., but also to monitor the sanitization process, distinguishing correctly and incorrectly sanitized areas through the presence or absence of luminescence, immediately, routinely, safely and economic. Once the objects, surfaces, footwear, etc. have been sanitized, the luminescent particles will only be present in those areas where the cleaning product has been applied and, therefore, will reveal the correctly and incorrectly sanitized areas to the user.

The sanitizing composition described in the first aspect is prepared by a procedure that comprises the following steps:

1. Synthesis of the luminescent agent, by encapsulation or union of one of the previously mentioned luminescent reagents with one of the previously described matrices, preferably by means of a covalent bond.

1.1. Choice of luminescent reagent, according to the needs of the application.

1.2. Incorporation of the luminescent reagent into a polymeric or inorganic matrix.

1.2.1. The luminescent reagent can be embedded in a polymeric or inorganic matrix simply by mixing it with the starting monomers (or any of them) before or during the polymerization reaction, or with the inorganic precursors that will form the inorganic matrix by hydrolysis and condensation reactions. , which can also be considered as "monomers" of said reaction. Methods for encapsulating or embedding a substance in a matrix are well known to the person skilled in the art and are part of the state of the art.

1 .2.2. The luminescent reagent can be attached to an inorganic matrix during its synthesis, or afterwards, through the sol-gel route, for example (J. Livage, C. Sanchez, M. Henry, S. Doeuff, “The chemistry of the sol-gel process”, Solid State Ionics 1989, 32-33, 633-638), by hydrolysis and condensation of oxide precursors of metallic elements and/or metalloids such as alkoxides, which, depending on the synthesis conditions, lead to to particles of a certain size and degree of aggregation. By way of example, it is possible to use the Stober method (and its derivatives) to obtain by sol-gel nanoparticles, porous or not, of a completely controllable size (W. Stober, A. Fink, “Controlled Growth of Monodisperse Silica Spheres in the Micron Size Range”. J. Colloid Interface Sci. 1968, 26, 62-69). The union can take place by direct reaction of the surface groups of the inorganic wall (for example, silanol groups (Si-OH) in the case of a SiCh matrix), with organic groups that the luminescent reagent possesses (such as carboxyls, amines, etc. .), with derivatives of the luminescent reagent that contain this type or other organic groups of interest, or even by indirect reaction, using an intermediate agent that facilitates the anchoring of the luminescent reagent in the matrix (for example, using organosilanes, R _x - SI-(OR')4-x, whose inorganic part (Si-OR') facilitates its anchoring to the matrix, while the organic part (R-Si) provides the groups of interest to anchor the luminescent reagent). These reactions generally take place in hydroalcoholic media (although other organic solvents are also used) at room temperature. If commercial or already prepared nanoparticles are used as matrix, it is advisable to ensure the presence of active surface groups (such as the silanols mentioned above) to be able to anchor intermediate agents such as 3~aminopropyltriethoxysilane (APTES), for which reason it is advisable to carry out a pretreatment that activates the surface (attaching it in an acid medium at room temperature, for example). If the luminescent reagent is anchored during the synthesis of the inorganic matrix itself, the inorganic precursors already incorporate this type of groups (such as silanols), capable of binding to the luminescent reagent in the manner described above, optionally being able to use an intermediate agent as co -precursor, during the condensation reaction, which would imply the co-condensation of several precursors to form an inorganic matrix that would incorporate organic groups within it. At this stage, it is also possible to modify the nature of the inorganic surface if it is of interest (polarity, reactivity, surface charge...). In the case of hydroalcoholic gels, it can be especially interesting to have apolar organic groups such as methyls, to make the surface more hydrophobic, thus reducing the interaction of the luminescent reagent with ambient humidity or the solvents of the sanitizing compositions (alcohols, etc.) , which could negatively affect luminescence, promoting decay. To do this, it would suffice to choose as co-precursor an organosilane reagent that incorporates the desired organic groups on the surface, for example, methyltrimethoxysilane (MTMS), which leaves a terminal methyl group in the matrix. Additionally, precursors with phosphonate groups would allow the incorporation of negative surface charges to the matrix, favoring the electrostatic repulsion of the luminescent agent and therefore a better distribution of the same in any sanitizing composition.

1.3. Optional modification of the nature of the surface of the matrix, if it has not been It was carried out in the previous step (for example in the case of already synthesized or commercial particles). In the case of the use of inorganic matrices, the modulation of characteristics such as polarity, reactivity, etc. they can be carried out a posteriori, using the same condensation reactions, with the appropriate reagents (generally organosilanes). In order to prevent decay, in addition to hydrophobizing the surface, the obtained luminescent agent can be re-encapsulated with an oxide layer (for example, SiOz, or even TiOz, whose higher refractive index also provides diffractive effects that can improve the luminescence).

2. Incorporation of the luminescent agent into a sanitizing composition of the different preferred embodiments. To do this, it is possible to use multiple strategies, which can be summarized in two types:

2.1. Direct incorporation of the luminescent agent into an already prepared and/or commercial sanitizing composition. For this, the luminescent agent is distributed in the sanitizing composition by physical methods, being able to use a dispersing agent that facilitates this task.

2.2. Incorporation of the luminescent agent during the preparation of the sanitizing composition. To do this, the luminescent agent is added in one of the stages of the preparation of the different sanitizing compositions. By way of example, in the case of hydroalcoholic gels, it is preferable to distribute the luminescent agent in the solvents that make it up, and finally add the thickening agent, to obtain a gel with optimal rheological properties for use.

In a preferred preparation procedure, the synthesis of the luminescent agent is addressed using oxides of metallic elements, metalloids, and even mixed oxides of said elements as inorganic matrix, preferably a matrix of SiOz and/or TiOz, porous or not.

In a preferred preparation procedure, the luminescent reagent of choice is a fluorescent reagent, preferably fluorescein (since it is tolerated by the human body in low concentrations in ophthalmic applications) or quinine (orally tolerated in low concentrations).

In a preferred preparation procedure, fluorescein is anchored on the surface of previously prepared or commercial nanoparticles of oxides of metallic elements, metalloids, and even mixed oxides of said elements, with a particle size greater than 200 nm. In a preferred embodiment of the procedure, SiOz or TiOz nanoparticles, porous or not, with a particle size greater than 200 nm, are used as inorganic matrix and, preferably, fluorescein is used as luminescent reagent. Said nanoparticles can be obtained with a controlled particle size by the aforementioned sol-gel route, either by the Stober method also mentioned (of a porous nature or not), or by sol-gel and self-assembly, using cetyltrimethylammonium bromide ( CTAB) as a structural directing agent (CT Kresge, ME Leonowicz, WJ Roth, JC Vartuli & JS Beck, “Ordered mesoporous molecular sieves synthesized by a liquid-crystal template mechanism”, Nature 1992, 359, 710-712).

As for TiOz nanoparticles, commercial particles that are generally non-porous can be used, and can also be obtained by the sol-gel route, and optionally by combining the sol-gel route and the self-assembly strategy, using Pluronic P123 as structural directing agent. (Y. Wan, D. Zhao, "On the Controllable Soft-Templating Approach to Mesoporous Silicates", Chem. Rev. 2007, 107(7), 2821-2860).

Porous nanoparticles are preferably chosen because they admit a greater amount of luminescent reagent per nanoparticle.

In a preferred preparation procedure, the luminescent agent obtained is added to a conventional hydroalcoholic gel in a proportion of 1-30% by weight, more preferably 1-10% by weight, using nanoparticles of more than 200 nm in diameter, which allows to ensure that the skin permeability will be practically nil, guaranteeing the complete dermatological safety of the product.

In another preferred preparation procedure, the luminescent agent obtained is added to a conventional hydroalcoholic gel in a proportion of 1-10% by weight, adding a dispersing agent (preferably glycerol or ethylene glycol) to the resulting mixture to promote better dispersion of the particles. nanoparticles in the hydroalcoholic gel, in a proportion of 0-10%, preserving the virucidal and bactericidal properties of the gel.

In another preferred preparation procedure, the luminescent agent obtained is it is added to a conventional cleaning product in a proportion of 1-30% by weight, more preferably between 1 and 10% by weight, using nanoparticles of more than 200 nm in diameter, which ensures that skin permeability will be practically nil, guaranteeing the complete dermatological safety of the product.

Another aspect of the invention refers to the use of the sanitizing composition defined in the first aspect of the invention for sanitizing surfaces and monitoring the sanitizing process.

In a preferred embodiment, the surfaces to be sanitized are parts of the human body, preferably the hands. In another preferred embodiment, the surfaces to be sanitized are surfaces of objects, such as the sole of footwear, or surfaces of establishments (floors and walls).

Therefore, the sanitizing composition of the invention could be used to monitor and ensure the correct cleaning of the hands of people who access establishments, hospitals and health centers (which would reduce the impact of nosocomial infections), large surfaces, etc., by washing hands with a luminescent hydroalcoholic gel, preferably fluorescent, followed by monitoring its luminescence (simple, with a UV lamp, or more complex, by means of a device equipped with cameras that automatically record the generated luminescence, and even calculate the properly sanitized area). This would make it possible to guarantee the correct sanitization of the hands of the people who access there, in a routine, safe, efficient and economic way. In addition, it would reveal the areas of the hands incorrectly cleaned by the user, who would learn to improve their washing technique, promoting healthier habits, and favoring better prevention of their own health, and that of others.

Another preferred application example would be the real-time monitoring of the correct hygiene of the footwear of users who access an establishment, hospitals, health centers, department stores, etc., which again would prevent the spread of diseases (nosocomial or not). ), by washing with a luminescent cleaning product, preferably fluorescent or phosphorescent, followed by monitoring its luminescence (simple, with a UV lamp, or more complex, by means of a device equipped with cameras that automatically record the luminescence generated , and even calculate the properly sanitized area). Additionally, the sanitizing composition of the invention could be used to monitor and ensure the correct cleaning of floors, walls and other surfaces in establishments, hospitals and health centers (which would reduce the impact of nosocomial infections), large surfaces, etc., guaranteeing even more the safety of the people who access there. Since the described sanitizing compositions are safe and efficient, they could be used routinely and economically.

Another aspect of the invention refers to the use of the luminescent agent described in the first aspect of the invention for the preparation of coatings for objects and/or surfaces, giving them luminescent and/or self-cleaning properties.

For this particular use, the coating would be made up of a Ti oxide matrix, and a luminescent reagent capable of exciting the matrix, preferably capable of emitting UV, such as, for example, and not exclusively, Li, Y or Ge oxides. doped with Eu ³⁺ , capable of emitting UV radiation persistently -hours- after being excited for a brief period of time, ZnO, Ag nanoparticles, "upconverting nanoparticles" capable of emitting UV radiation when stimulated with IR radiation, plus economic, etc., which favors the generation of free radicals on the surface of the TÍO2 coating, capable of oxidizing the organic matter located on it, guaranteeing the sanitization of the coating surface.

Thus, the use of this type of coating on floors, walls or objects would allow them to be disinfected comfortably, and have luminescent properties simultaneously, which could be interesting, for example, to sanitize rooms (for example, in hospitals), with minimal radiation costs. (UV or even IR).

A final aspect of the invention refers to the use of a luminescent agent as mentioned in the first aspect of the invention for the preparation of a sanitizing composition. This sanitizing composition can be a hydroalcoholic gel or a conventional cleaning product as described in the first aspect of the invention.

Throughout the description and claims the word "comprises" and its variants are not intended to exclude other technical characteristics, additives, components or steps. For those skilled in the art, other objects, advantages and characteristics of the invention are will appear in part from the description and in part from the practice of the invention. The following examples are provided by way of illustration, and are not intended to be limiting of the present invention.

PREFERRED EMBODIMENT OF THE INVENTION

An example of an embodiment of the sanitizing composition according to the present invention is indicated below in order to illustrate the same.

Example 1: Preparation of a luminescent agent

1.1 Preparation of a luminescent agent with fluorescein as luminescent reagent and a matrix comprising SiO2.

Following a procedure based on the Stober method (W. Stober, A. Fink, “Controlled Growth of Monodisperse Silica Spheres in the Micron Size Range”. J. Colloid Interface Sci. 1968, 26, 62-69) and sol chemistry -gel, 3 mL of fluorescein isothiocyanate (FITO) is reacted with 2 mL of (3-aminopropyl)triethoxysilane (APTES) in 330 mL of ethanol (EtOH), and the resulting solution is left stirring for 2h in the dark and inert atmosphere . In the case of the synthesis of a luminescent agent formed by dense fluorescent silica nanoparticles, the resulting solution is diluted in 1 L of EtOH, and 50 mL of tetraethyl orthosilicate (TEOS) (source of SO2), 80 mL of water are added. distilled, and 80 mL of ammonia (NH4OH), allowing the mixture to react for 17h under gentle stirring and in the dark. After said time, aggregates of non-porous silica nanoparticles are obtained that incorporate within them fluorescein molecules capable of fluorescing when illuminated by UV light, but covalently anchored to the silica matrix so that not even the luminescent reagent can penetrate the skin. dissolved in the solvent of the sanitizing composition, nor the aggregates of nanoparticles, since they are micrometric in size (verified by FESEM, field emission scanning electron microscopy).

Optionally, in order to favor the dispersion of the luminescent agent particles in a sanitizing composition, it is possible to modify their surface by incorporating surface organic groups that provide different properties. As an example, in the previous synthesis, the 50 mL of TEOS can be replaced by half TEOS, and half an organosiloxane that provides surface charges. negative substances that promote interparticle repulsion, such as the sodium salt of 3-trihydroxysilylpropylmethylphosphonate.

1.2 Preparation of another luminescent agent with fluorescein as the luminescent reagent and a matrix comprising

20 mg of fluorescein isothiocyanate (FITC) is reacted with 2 mL of (3-aminopropyl)triethoxysilane (APTES) in 1 L of ethanol (EtOH) for 2h, stirring in the dark and in an inert atmosphere. To the resulting solution, 20 g of porous SIO2 nanoparticles between 350 and 450 nm are added, previously obtained by a modification of the Stóber method with self-assembly (J. El Haskouri, J.M. Morales, D. Ortiz de Zárate, L. Fernández, J. Latorre, C. Guillem, A. Beltrán, D. Beltrán, P. Amorós, "Nanoparticulated silicas with bimodal porosity: chemical control of the pore sizes", Inorg. Chem. 2008, 47(18), 8267-77) , leaving the mixture in agitation and darkness between 15 and 24h, to guarantee the correct reaction of the APTES functionalized with fluorescein with the surface hydroxyls of the particles (Si-OH), anchoring the luminescent reagent to the surface (external and internal) of the particles. covalently shaped nanoparticles, so that they cannot freely dissolve in the sanitizing composition solvent, and penetrate the skin.

1.3. Preparation of another luminescent agent with fluorescein as luminescent reagent and a matrix comprising TÍO ₂ ,

20 mg of fluorescein isothiocyanate (FITC) is reacted with 2 mL of (3-aminopropyl)triethoxysilane (APTES) in 1 L of ethanol (EtOH) for 2h, stirring in the dark and in an inert atmosphere. To the resulting solution, 20 g of porous TÍO2 nanoparticles previously obtained by sol-gel and self-assembly are added (D. Ortiz de Zárate, S. Serna, S. Ponce-Alcántara, M.Kovylina and J. García-Rupérez, “Bottom -Up Synthesis of Mesoporous TÍO2 Films for the Development of Optical Sensing Layers”, Chemosensors 2021 , 9, 329), leaving the mixture under agitation and darkness between 15 and 24h, to guarantee the correct reaction of the APTES functionalized with fluorescein with the surface hydroxyls of the particles (Ti-OH), thus anchoring the luminescent reagent to the surface (external and internal) of the nanoparticles covalently, so that it cannot dissolve freely in the sanitizing composition solvent and penetrate the skin. Example 2: Preparation of a sanitizing composition comprising the luminescent agent prepared in Example 1.

In a procedure for preparing a preferred sanitizing composition, the luminescent agent obtained in Example 1, which consists of micrometric aggregates of fluorescent particles, is added to a conventional hydroalcoholic gel in a proportion of 10% by weight. Finally, 7% by weight of glycerol is added to the resulting mixture, which improves the dispersion of the nanoparticle aggregates in the hydroalcoholic gel, preserving the virucidal and bactericidal properties of the gel. The end result is a hydroalcoholic gel that turns fluorescent yellow when illuminated with UV light.

The luminescent agent prepared in any of Examples 1.2 could be used in the same way. or 1.3. to prepare the sanitizing composition.

Example 3: Use test and monitoring of the composition prepared in Example 2:

The fluorescent hydroalcoholic gel obtained is applied in a conventional hand cleaning process (without following the protocol recommended by the WHO, precisely to favor the presence of incorrectly sanitized areas, preventing the gel from reaching the entire surface of the hand). The hydroalcoholic gel, when applied to the skin, does not alter its natural color. The presence of the luminescent agent does not alter the sensation of cleanliness offered by conventional hydroalcoholic gel without the agent. When illuminating the hands with UV light, fluorescence is observed only in the areas where this sanitizing composition has been applied, not in the areas where the gel has not reached, thus allowing monitoring if the hand sanitizing process has been carried out correctly. , and the areas where the user must affect to improve their hand cleaning technique. To the naked eye and under UV lighting, the areas without gel are perceived as an intense pink color, while the areas that have received gel are perceived more bluish/purple, although the areas where more gel has accumulated, and therefore more nanoparticles, they present a more evident yellow fluorescence. When the UV light is removed, the hands are perceived as normal. Finally, the user can optionally remove the fine layer of nanoparticle aggregates from their hands by mechanical action, rubbing their hands, rubbing with hand-drying paper, or even by washing again with conventional hydroalcoholic gel.

Claims

1. Sanitizing composition characterized by comprising a luminescent agent, wherein said agent comprises:

-a luminescent reagent in an amount between 0.1 and 10% by weight with respect to the total weight of the luminescent agent and

- a polymeric and/or inorganic matrix in an amount between 90 and 99.9% by weight with respect to the total weight of the luminescent agent, and where the luminescent reagent is embedded and/or attached to the matrix by ionic or covalent bonding, where the luminescent agent is in the form of particles with a size greater than 200 nm or in the form of particle aggregates with an aggregate size greater than 200 nm.

2. Sanitizing composition, according to claim 1, wherein the amount of luminescent reagent in the luminescent agent is between 0.1 and 5% by weight.

3. Sanitizing composition, according to claim 2, wherein the amount of luminescent reagent in the luminescent agent is between 0.1 and 1% by weight.

4. Sanitizing composition, according to any of the preceding claims, wherein the luminescent reagent is a fluorescent reagent selected from: fluorescein, quinine, rhodamine, cresyl violet, cyanines, tryptophan, 1,4-Bis(5-phenyl-2-oxazolilfbenzene , tyrosine or derivatives thereof selected from their salts and isothiocyanates, quantum dots, conversion nanoparticles, metal nanoparticles and oxides of Li, Y or Ge doped with Eu ³⁺ .

5. Sanitizing composition according to any of the preceding claims, wherein the luminescent reagent is fluorescein or quinine.

6. Sanitizing composition according to any of the preceding claims, wherein the amount of matrix in the luminescent agent is between 95 and 99.9% by weight.

7. Sanitizing composition, according to claim 6, wherein the amount of matrix in the luminescent agent is between 99 and 99.9% by weight.

8. Sanitizing composition according to any of the preceding claims, wherein the matrix is inorganic in nature and comprises or consists of an oxide of a metallic element or a metalloid element, or mixed oxides of said metal and/or metalloid elements.

9. Sanitizing composition, according to claim 8, where the matrix comprises or consists of an oxide of an element selected from: Si, Ti, Zr, Al and Zn or a mixed oxide of elements selected from Si, Ti, Zr, Al and Zn .

10. Sanitizing composition, according to claim 9, wherein the matrix comprises or consists of SiOs or TiOz.

11. Sanitizing composition, according to any of the preceding claims, where the union of the luminescent reagent and the matrix is by covalent bond.

12. Sanitizing composition according to any of the preceding claims, wherein the luminescent agent has a particle size between 400 and 500 nm, or between 800 and 1000 nm, or is in the form of aggregates with a size between 200 and 1000 nm.

13. Sanitizing composition according to any of the preceding claims, wherein the luminescent agent is present in a percentage by weight of between 1 and 30% in the sanitizing composition.

14. Sanitizing composition, according to claim 13, wherein the luminescent agent is present in a percentage by weight of between 1 and 10% in the sanitizing composition.

15. Sanitizing composition, according to any of the preceding claims, wherein said composition is a hydroalcoholic gel or a conventional cleaning product for cleaning any surface.

16. Sanitizing composition according to any of the preceding claims, wherein said composition is a hydroalcoholic gel with a minimum content of 70% by weight or volume in ethanol and/or isopropanol.

17. Use of the sanitizing composition defined in any of claims 1 to 16 for sanitizing surfaces and/or monitoring the sanitizing process.

18. Use according to claim 17, where the surface to be sanitized is that of the hands.

19. Use according to claim 17, where the surface to be sanitized is that of the shoe soles.

20. Use according to claim 17, where the surface to be sanitized is the surface of an object or any of the parts of a selected floor and wall establishment.

21. Use of the sanitizing composition defined in any of claims 1 to 16 for the preparation of coatings for objects and/or surfaces, giving them luminescent and/or self-cleaning properties.

22. Use of a luminescent agent as defined in any of claims 1 to 12 for the preparation of a sanitizing composition.