Porous silica and its use

Abstract

The embodiment of the present application discloses a kind of porous silica and its application.The preparation method of the porous silica includes: (1) the aqueous solution of cetyltrimethylammonium chloride, triethanolamine and water are mixed, using sodium hydroxide aqueous solution to adjust system pH to basic, to obtain first solution;(2) tetraethyl orthosilicate, amino-containing triethoxysilane and cyclohexane are mixed, to obtain second solution;(3) under heating and stirring, slowly drop second solution into first solution, after drop is finished, keep warm and continue stirring, then by centrifugation, washing and drying, to obtain the porous silica.The present application applies porous silica to oral care products, in addition to effectively removing hydrogen sulfide such volatile sulfide, it can also play the basic function of silica, without adding other breath freshening ingredients, thereby reducing the production cost of breath freshening oral care products, economic benefit and social benefit are remarkable.

Description

Technical Field

[0001] This invention relates to the field of oral care technology, specifically to a porous silica and its applications. Background Technology

[0002] Halitosis is a common medical term used to describe an unpleasant odor in exhaled air. Most cases of halitosis are attributed to oral factors, including poor oral hygiene, dry mouth, gingivitis, and periodontitis. The most common manifestation of halitosis is bad breath, which is caused by the putrefaction of a mixture of saliva, food debris, and shed cells in the mouth by microorganisms, producing various substances such as volatile sulfur compounds, short-chain fatty acids, and diamines, ultimately leading to bad breath. For the intervention of halitosis, in addition to physical and mechanical treatments, oral care products containing specific active ingredients, such as chlorhexidine and hexadecylpyridinium chloride, have also provided convincing results. However, long-term use of chlorhexidine and hexadecylpyridinium chloride may cause discoloration of teeth and mucous membranes and taste abnormalities. Therefore, the search for safer and more natural breath-freshening active ingredients has become the mainstream approach.

[0003] Commercially available oral care products claiming to freshen breath often achieve this effect by adding medications, chemicals, or prebiotics. For example, Chinese Patent 112336678B discloses a breath-freshening toothpaste containing lysozyme, borneol, osmanthus, plant extracts, and propolis. The synergistic effect of these substances effectively combats Helicobacter pylori, enhances antibacterial activity, removes odors, and freshens breath. Others achieve this effect by adding traditional Chinese medicine extracts. For instance, Chinese Patent 114177123B discloses an aromatic herbal toothpaste containing extracts of Eupatorium fortunei, Cynanchum paniculatum, and Perilla frutescens. This herbal toothpaste has been verified to have a certain breath-freshening effect. However, current breath-freshening technologies all require adding additional breath-freshening ingredients to ordinary toothpaste formulas, increasing production costs.

[0004] Silica, due to its stable physicochemical properties, excellent abrasive ability, and good compatibility, is widely used in the development of toothpaste products. In existing technologies, porous silica is generally recognized as a good adsorbent material due to its large specific surface area. However, ordinary silica materials have limited affinity for hydrogen sulfide; therefore, porous silica must be appropriately modified with functional groups before it can be used for hydrogen sulfide adsorption. Current technologies mainly focus on post-amined silica modification, which involves wet impregnating existing silica materials to graft amino-containing molecules onto the surface, thereby enabling the removal of volatile sulfide gases (taking hydrogen sulfide as an example) (Journal of Industrial and Engineering Chemistry, 2012, 18, 169-173; Industrial & Engineering Chemistry Research, 2010, 49, 11408-11414). However, these methods suffer from problems such as complex processes, difficulty in impurity removal, and loss of amino molecules (Separation & Purification Reviews, 2019, 48, 78-89). Therefore, there is a need to develop other stable and convenient silica that can freshen breath. Summary of the Invention

[0005] Therefore, embodiments of the present invention provide a porous silica and its application. The porous silica provided by the present invention carries amino groups on its surface, which facilitates the removal of hydrogen sulfide gas, thereby achieving the purpose of freshening breath.

[0006] To achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0007] According to a first aspect of the present invention, the present invention provides porous silica, wherein the method for preparing the porous silica includes the following steps:

[0008] (1) Mix hexadecyltrimethylammonium chloride aqueous solution, triethanolamine and water, and adjust the pH of the system to alkaline using sodium hydroxide aqueous solution to obtain the first solution;

[0009] (2) Tetraethyl orthosilicate, amino-containing triethoxysilane and cyclohexane are mixed to obtain a second solution;

[0010] (3) Under heating and stirring, the second solution is slowly added dropwise to the first solution. After the addition is complete, the solution is kept warm and stirred continuously. Then, the porous silica is obtained by centrifugation, washing and drying.

[0011] Furthermore, the amino-containing triethoxysilane is (3-aminopropyl)triethoxysilane or N-(2-aminoethyl)-3-aminopropyltriethoxysilane.

[0012] Further, in step (1), the concentration of the hexadecyltrimethylammonium chloride aqueous solution is 100 mg / mL, and the volume-to-mass ratio of the hexadecyltrimethylammonium chloride aqueous solution, triethanolamine, and water is 40 mL: 0.3 g: 60 mL; the concentration of the sodium hydroxide solution is 2 M, and the pH value of the system is 8.5 ± 0.2;

[0013] In step (2), the volume ratio of tetraethyl orthosilicate, amino-containing triethoxysilane and cyclohexane is 0.6-1.8:0.2-1.4:18; the mass ratio of the first solution and the second solution is 3:1.

[0014] Furthermore, in step (3), the heating temperature is 30-50°C, and the stirring time is 15-30 hours.

[0015] According to a second aspect of the present invention, the present invention provides the use of porous silica as described above in the preparation of oral care products.

[0016] Furthermore, the oral care product is toothpaste or tooth powder.

[0017] Furthermore, the oral care product includes the porous silica, wherein the porous silica comprises 0.05-5% by mass in the oral care product.

[0018] Furthermore, the oral care product also includes excipients and deionized water, wherein the excipients are selected from at least one of humectants, abrasives, thickeners, foaming agents, taste modifiers, fragrances, pH adjusters, and preservatives.

[0019] In some specific embodiments, the toothpaste comprises, by weight percentage: 15-40% humectant, 35-50% abrasive, 1-5% thickener, 2-4% foaming agent, 0.1-0.3% taste modifier, 0.5-1.5% fragrance, 0.05-5% porous silica, 0.05-0.1% preservative, with the balance being deionized water. The humectant is at least one of glycerin, polyethylene glycol, propylene glycol, and sorbitol; the abrasive is at least one of calcium carbonate, dicalcium phosphate, and silica (hydrated silica); the thickener is at least one of xanthan gum, carrageenan, carbomer, and cellulose gum; the foaming agent is at least one of sodium lauryl sulfate, sodium methyl taurate, and cocoylpropyl betaine; the taste modifier is at least one of sodium saccharin, sucralose, and xylitol; the fragrance is a flavoring, including but not limited to food flavorings and essential oils; and the preservative is sodium benzoate, etc. The production process is as follows: Dissolve the flavor improver and preservative in deionized water according to the formula, then place them in a vacuum reactor. Under vacuum stirring, add the humectant, abrasive, thickener, foaming agent and porous silica, and continue stirring until uniform. Then add the fragrance and stir until uniform.

[0020] In some specific embodiments, the tooth powder, by weight percentage, comprises: 20-50% abrasive, 1-10% humectant, 0.5-2% foaming agent, 0.5-5% taste modifier, 0.5-1.5% flavoring agent, 0.05-5% porous silica, and the balance being sorbitol. The abrasive is at least one of silica, calcium hydrogen phosphate, and calcium carbonate; the humectant is at least one of erythritol and β-glucan; the foaming agent is at least one of sodium lauroyl glutamate and sodium lauroyl sulfate; the taste modifier is at least one of sodium saccharin, sucralose, and xylitol; and the flavoring agent is a fragrance, including but not limited to food flavorings and essential oils. The manufacturing process is as follows: the porous silica, abrasive, humectant, foaming agent, taste modifier, and flavoring agent are placed in a mixing pot according to the specified ratio and mixed evenly. Then, sorbitol is added and mixed evenly. The temperature of the mixing pot should not exceed 35°C.

[0021] The embodiments of the present invention have the following advantages:

[0022] 1. Triethoxysilanes containing amino groups can be easily incorporated into porous silica nanoparticles through dehydration condensation between silanol groups, resulting in a certain amount of amino groups in the final product that cannot be removed. This process can produce porous silica containing amino groups in one step, without the need for step-by-step impregnation.

[0023] 2. This invention applies porous silica to oral care products. In addition to effectively removing volatile sulfides such as hydrogen sulfide, it can also perform the basic functions of silica. There is no need to add other breath-freshening ingredients, thereby reducing the production cost of breath-freshening oral care products, resulting in significant economic and social benefits. Detailed Implementation

[0024] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Example 1

[0026] This embodiment provides a porous silica, the preparation method of which includes the following steps:

[0027] (1) Add 40 mL of hexadecyltrimethylammonium chloride aqueous solution with a concentration of 100 mg / mL and 0.3 g of triethanolamine to 60 mL of water, stir well, and then use sodium hydroxide aqueous solution (2M) to adjust the pH of the system to 8.5 ± 0.2 to form solution 1.

[0028] (2) Add 1.8 mL of tetraethyl orthosilicate and 0.2 mL of (3-aminopropyl)triethoxysilane to 18 mL of cyclohexane and stir until homogeneous to form solution 2.

[0029] (3) Take 60 mL of solution 1 from step (1), stir and heat to 40°C for 30 minutes, slowly add solution 2 from step (2) (1 drop / second), keep the temperature at 40°C, and continue stirring for 18 hours after the addition is complete. Then, purify by centrifugation and washing with ethanol, and finally wash the product with water and dry it at 40°C for 24 hours to obtain porous silica.

[0030] Example 2

[0031] This embodiment provides a porous silica, the preparation method of which is similar to that of Example 1, except that:

[0032] Step (2): Add 1.4 mL of tetraethyl orthosilicate and 0.6 mL of (3-aminopropyl)triethoxysilane to 18 mL of cyclohexane and stir until homogeneous to form solution 2.

[0033] Example 3

[0034] This embodiment provides a porous silica, the preparation method of which is similar to that of Example 1, except that:

[0035] Step (2): Add 1 mL of tetraethyl orthosilicate and 1 mL of (3-aminopropyl)triethoxysilane to 18 mL of cyclohexane and stir until homogeneous to form solution 2.

[0036] Example 4

[0037] This embodiment provides a porous silica, the preparation method of which is similar to that of Example 1, except that:

[0038] Step (2): Add 0.6 mL of tetraethyl orthosilicate and 1.4 mL of (3-aminopropyl)triethoxysilane to 18 mL of cyclohexane and stir until homogeneous to form solution 2.

[0039] Example 5

[0040] This embodiment provides a porous silica, the preparation method of which is similar to that of Example 1, except that:

[0041] Step (2): Add 0.8 mL of tetraethyl orthosilicate and 1.2 mL of N-(2-aminoethyl)-3-aminopropyltriethoxysilane to 18 mL of cyclohexane and stir until homogeneous to form solution 2.

[0042] Comparative Example 1

[0043] This comparative example provides a porous silica, the preparation method of which is similar to that of Example 1, except that:

[0044] Step (2): Add 2 mL of tetraethyl orthosilicate to 18 mL of cyclohexane and stir until homogeneous to form solution 2.

[0045] Example 6

[0046] This embodiment provides a toothpaste, the raw materials of which, by weight percentage, are: 25% sorbitol, 10% glycerin, 30% dicalcium phosphate, 7% silica, 0.7% xanthan gum, 0.3% cellulose gum, 2% sodium lauryl sulfate, 0.2% sodium saccharin, 1% food flavoring, 0.05% porous silica from Example 3, 0.05% sodium benzoate, with the remainder made up to 100% with deionized water.

[0047] The preparation method of the toothpaste is as follows: Dissolve the taste improver and preservative in deionized water according to the ratio, pour it into a vacuum reactor, add humectant, abrasive, thickener, foaming agent and porous silica under vacuum stirring and continue stirring until uniform, then add fragrance and stir until uniform.

[0048] Example 7

[0049] This embodiment provides a toothpaste, the raw materials of which, by weight percentage, are: 20% sorbitol, 7% polyethylene glycol, 5% glycerin, 35% calcium carbonate, 10% silica, 0.7% xanthan gum, 0.2% carrageenan, 0.2% carbomer, 1.5% sodium lauryl sulfate, 1.5% cocoylpropyl betaine, 0.15% sucralose, 1.5% food flavoring, 2% porous silica (Example 3), and 0.05% sodium benzoate, with the remainder made up to 100% with deionized water.

[0050] The preparation method of the toothpaste is the same as in Example 6.

[0051] Example 8

[0052] This embodiment provides a toothpaste, the raw materials of which, by weight percentage, are: sorbitol 22%, polyethylene glycol 10%, propylene glycol 5%, silica 45%, cellulose gum 0.7%, carrageenan 0.4%, sodium lauryl sulfate 1%, sodium methyl taurate 2%, xylitol 5%, food flavoring 1.5%, porous silica from Example 3 5%, sodium benzoate 0.05%, with the remainder made up to 100% with deionized water.

[0053] The preparation method of the toothpaste is the same as in Example 6.

[0054] Example 9

[0055] This embodiment provides a tooth powder, the raw materials of which, by weight percentage, are: 20% dicalcium phosphate, 20% silicon dioxide, 5% erythritol, 1.5% sodium lauroyl sulfate, 0.5% sodium saccharin, 1.5% food flavoring, 2% porous silicon dioxide from Example 2, and the remainder is made up to 100% with sorbitol.

[0056] The preparation method of the above-mentioned tooth powder is as follows:

[0057] Under conditions where the temperature does not exceed 35℃, place porous silica, abrasive, humectant, foaming agent, flavor modifier and fragrance in a mixing pot according to the formula, mix well, then add sorbitol and stir well.

[0058] Example 10

[0059] This embodiment provides a tooth powder, the raw materials of which, by weight percentage, are: 25% dicalcium phosphate, 15% silicon dioxide, 3% β-glucan, 1% sodium lauroyl sulfate, 1% sodium lauroyl glutamate, 0.5% sucralose, 1.2% food flavoring, 5% porous silicon dioxide from Example 2, and the balance is made up to 100% with sorbitol.

[0060] The preparation method of the above-mentioned tooth powder is the same as that in Example 9.

[0061] Comparative Example 2

[0062] This comparative example provides a toothpaste whose raw materials and preparation method are basically the same as those in Example 7, except that the porous silica of Example 3 is replaced with an equal amount of porous silica of Comparative Example 1.

[0063] Test Example 1

[0064] Characterization of porous silica

[0065] The morphology and specific surface area of ​​the porous silica in Examples 1-5 and Comparative Example 1 were characterized. The results are shown in Table 1 below.

[0066] Table 1

[0067] sample Diameter (nm) PDI <![CDATA[Specific surface area (m 2 / g)]]> Zeta potential (mV) Example 1 135 0.117 754 30.7 Example 2 117 0.168 778 32.8 Example 3 121 0.149 746 32.5 Example 4 104 0.155 739 33.8 Example 5 108 0.135 724 36.5 Comparative Example 1 98 0.201 784 -21.7

[0068] The results above show that the products provided in each embodiment and comparative example have uniform morphology. The addition of amino-containing triethoxysilane affects the physical structure of the final product, but the effect is limited. However, it has a significant impact on the zeta potential of the final product surface, which reflects that the amino-containing triethoxysilane has been successfully incorporated into the final product.

[0069] Test Example 2

[0070] Porous silica removes hydrogen sulfide

[0071] The hydrogen sulfide removal effect of porous silica in Examples 1-5 and Comparative Example 1 was evaluated according to the laboratory evaluation method for the inhibition of volatile sulfur compounds (VSCs) in oral hygiene products, as per T / COCIA 19-2022. Details are as follows:

[0072] Preparation of bacterial suspension: Take a lyophilized bacterial culture tube, open it under aseptic conditions, add an appropriate amount of bovine heart and brain infusion medium, and gently blow and aspirate several times to dissolve and disperse the bacteria. Take a test tube containing 5-10 mL of bovine heart and brain infusion medium, add a small amount of bacterial suspension, and place it in an anaerobic jar at 36±1℃ for 24-48 hours to obtain the first generation culture. Use an inoculation loop to take the bacterial suspension from the first generation culture and streak it onto a bovine heart and brain infusion agar plate. Additional nutrients may be added depending on the growth of the strain. If growth is poor, 5%-10% fresh sterile defibrinated sheep blood can be added. *Porphyromonas gingivalis* is anaerobically cultured at 36±1℃ for 3-5 days, and *Prevotella intermedius* is anaerobically cultured at 36±1℃ for 5-7 days to obtain the second generation culture. Typical colonies from the second-generation culture were selected, inoculated onto bovine heart and brain infusion agar medium, and placed in an anaerobic jar at 36±1℃ for the corresponding time to obtain the third-generation culture.

[0073] During the experiment, fresh cultures from bovine heart and brain infusion agar slant were taken from generations 3 to 5. The morphology and size of the bacteria were examined under a microscope using pre-Gram staining. 5 mL of PBS was added to the slant tube, and the bacterial growth was washed off by repeated pipetting and aspiration. The washing solution was then transferred to another sterile turbidity tube and mixed thoroughly using a vortex mixer.

[0074] The initially prepared bacterial suspension was first diluted to the required concentration using a bacterial concentration turbidimetric assay. The initial bacterial concentrations of *Porphyromonas gingivalis* and *Prevotella intermedius* were adjusted to 10-1. 6 ~10 7 cfu / mL, prepare fresh before use.

[0075] Sample preparation: Weigh 5g of sample into a 50mL centrifuge tube, add 15mL of deionized water and vortex until evenly dispersed.

[0076] Add 9 mL of bovine heart and brain extract liquid culture medium to a glass test tube (18 mm * 180 mm), seal tightly with a silicone stopper, and autoclave at 121 °C for 15 minutes before use. Add 500 μL of fresh, sterile, defibrinated sheep blood, 1 mL of bacterial suspension (Porphyromonas gingivalis: Prevotella intermedius = 1:10), and 0.2 mL of the experimental sample solution sequentially. Use sterile distilled water as the blank group and the test sample solution as the test sample group. Set up 5 replicates for each group. After sealing with a silicone stopper and plastic wrap, place in an anaerobic jar and incubate anaerobically at 36 ± 1 °C for 24 hours to produce gas. If bacterial growth is poor, use a vial of the same volume with an aluminum cap instead of the glass test tube. Remove the air from the vial using anaerobic equipment before incubating at 36 ± 1 °C.

[0077] Hydrogen sulfide test: Take out the test tubes of each experimental group, shake to mix the gas in the test tubes, and use iSenLabTWINBREASOR II for testing (due to the extreme value of the instrument, the gas generated by the culture medium is diluted by 1 part with air during the test).

[0078] The clearance rate was calculated using the formula: Clearance rate = (1 - Agar medium test value / Sterile distilled water test value) × 100%. The results are shown in Table 2 below.

[0079] Table 2

[0080]

[0081]

[0082] The results show that the porous silica provided in Comparative Example 1 has a certain ability to remove hydrogen sulfide, but it is not strong. After incorporating amino-containing molecules during the preparation of the porous silica, its ability to remove hydrogen sulfide is greatly enhanced. Further analysis reveals that the hydrogen sulfide removal ability gradually increases as the amount of amino-containing triethoxysilane incorporated gradually increases (Examples 1-3). However, when the amount is further increased (Example 4), the hydrogen sulfide removal ability does not significantly increase. This may be because the specific surface area of ​​the final product is reduced, and some amino groups may exist inside the silica rather than on the surface. Its adsorption capacity is directly proportional to the hydrogen sulfide diffusion rate and specific surface area, while the diffusion rate is inversely proportional to the diffusion distance; therefore, the adsorption kinetics are somewhat weakened.

[0083] Test Example 3

[0084] Toothpaste stability test

[0085] The stability test was conducted according to section 5.6 of GB / T 8372-2017. Specifically, two samples each of the toothpaste from Examples 6-8 and the tooth powder from Examples 9-10 were prepared. The first sample was stored at room temperature; the second sample was placed in a 48°C incubator. After one month, the samples were removed and allowed to return to room temperature before their properties were observed and pH was tested. The results are shown in Table 3 below.

[0086] The pH test for toothpaste is as follows: Weigh 5g of toothpaste (accurate to 0.01g), place it in a 50ml beaker, add 20mL of pre-boiled and cooled distilled water, stir thoroughly, and measure the pH using a pH meter (GB / T8372-2017); The pH test for tooth powder is as follows: Weigh 5g (accurate to 0.01g) of tooth powder, place it in a 100mL beaker, add 45mL of pre-boiled and cooled distilled water, stir thoroughly, and measure the pH using a pH meter (QB / T2932-2008).

[0087] Table 3

[0088]

[0089]

[0090] The results showed that after the samples of Examples 6-10 were stored at high temperature, their color, characteristic properties and pH remained basically the same as those of the samples at room temperature, with no significant changes, indicating that the oral care product provided by the present invention has good stability.

[0091] Test Example 4

[0092] Fresh breath effect

[0093] Twenty individuals with significant oral halitosis were randomly divided into two groups of 10 each, using the toothpastes from Example 7 and Comparative Example 2, respectively. The anti-halitosis efficacy of toothpastes was evaluated using the iSenLab TWINBREASOR II method, following the clinical method for evaluating the efficacy of oral hygiene products toothpaste in T / COCIA9-2020.

[0094] The results of the subjects' test on the first day were used as the initial indicator. After using the corresponding toothpaste for 4 days, the test was conducted at the same time as the first day as the effect indicator. The results are shown in Table 4 below.

[0095] Table 4

[0096]

[0097] The results showed that the toothpaste of Example 7 had a better breath-freshening effect than the toothpaste of Comparative Example 2. This may be because, although porous silica has a large specific surface area, which is conducive to the adsorption of gas molecules, silica itself has limited adsorption capacity for hydrogen sulfide gas. Therefore, the toothpaste prepared in Comparative Example 2 could only slightly reduce the concentration of hydrogen sulfide in the oral cavity. However, in Example 7, because porous silica contains amino groups, these amino groups form weak chemical bonds with thiol groups, thereby binding hydrogen sulfide molecules in the oral cavity, which are then washed away with rinsing to remove volatile sulfides. Therefore, Example 7 has a better breath-freshening effect than Comparative Example 2.

[0098] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A porous silica characterized by, The method for preparing the porous silica includes the following steps: (1) Mix hexadecyltrimethylammonium chloride aqueous solution, triethanolamine and water, and adjust the pH of the system to alkaline using sodium hydroxide aqueous solution to obtain the first solution; (2) Tetraethyl orthosilicate, amino-containing triethoxysilane and cyclohexane are mixed to obtain a second solution; (3) Under heating and stirring, the second solution is slowly added dropwise to the first solution. After the addition is completed, the solution is kept warm and stirred continuously. Then, the solution is centrifuged, washed and dried to obtain the porous silica. The amino-containing triethoxysilane is (3-aminopropyl)triethoxysilane or N-(2-aminoethyl)-3-aminopropyltriethoxysilane; In step (1), the concentration of the hexadecyltrimethylammonium chloride aqueous solution is 100 mg / mL, and the volume-to-mass ratio of the hexadecyltrimethylammonium chloride aqueous solution, triethanolamine, and water is 40 mL:0.3 g:60 mL; the concentration of the sodium hydroxide aqueous solution is 2M, and the pH value of the system is 8.5±0.

2. In step (2), the volume ratio of tetraethyl orthosilicate, amino-containing triethoxysilane and cyclohexane is 1:1:18; the volume ratio of the first solution and the second solution is 3:

1.

2. The porous silica of claim 1, wherein, In step (3), The heating temperature is 30-50℃, and the stirring time is 15-30 hours; The drying temperature is 40-45℃, and the time is 18-24 hours.

3. The use of the porous silica according to claim 1 or 2 in the preparation of oral care products.

4. Use according to claim 3, characterized in that, The oral care products mentioned are toothpaste and tooth powder.

5. Use according to claim 4, characterized in that, The oral care product includes the porous silica, and the porous silica accounts for 0.05-5% of the oral care product by mass.

6. Use according to claim 5, characterized in that, The oral care product also includes excipients and deionized water, wherein the excipients are selected from at least one of humectants, abrasives, thickeners, foaming agents, taste modifiers, fragrances, pH adjusters, and preservatives.

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