WO2022263505A1

WO2022263505A1 - Methods of solid phase wax coating of an active ingredient

Info

Publication number: WO2022263505A1
Application number: PCT/EP2022/066296
Authority: WO
Inventors: Sara MADARSHAHIAN; Mojtaba ENAYATINOOK; Alireza ABBASPOURRAD; Gerhard Ufheil; Bing Yan; Timothy James Wooster
Original assignee: Société des Produits Nestlé S.A.; Cornell University
Priority date: 2021-06-16
Filing date: 2022-06-15
Publication date: 2022-12-22

Abstract

A stable nutritional product has a variety of health and pharmaceutical benefits that make it essential to be used as a high dose supplement. Solid phase wax coating for coating highly water-soluble active ingredient uses natural waxes and food grade oil and surfactants. The product and method provide an effective barrier for delayed and controlled release of an active ingredient dispersion into water and drinks with an improved mouthfeel.

Description

TITLE

METHODS OF SOLD) PHASE WAX COATING OF AN ACTIVE INGREDIENT

BACKGROUND

[0001] The present disclosure is related to a method of making high loading encapsulated active ingredient granules prepared from food safe and supplement safe materials, for example, which may have the regulatory status as “generally recognized as safe” (GRAS) materials, particularly via a solid phase wax coating for coating highly water-soluble active ingredient by using natural waxes and food grade oil and surfactants. The present disclosure provides an effective barrier for delayed and controlled release of an active ingredient dispersion into water and drinks with an improved mouthfeel.

[0002] An example of one such active ingredient is N-acetylcysteine (“NAC”). NAC is a prodrug, antioxidant, a precursor for the glutathione, and a supplement form of semi-essential amino acid, cysteine. NAC has been used as a mucolytic agent and antidote for paracetamol overdose and alcohol intoxication, and is sold as an over-the-counter nutritional supplement because of its unique health benefits. NAC is used to enhance intestinal health and treat many diseases and disorders, such as cancer, cardiovascular diseases, insulin resistant and type-2 diabetes, alcoholic liver disease, chronic bronchitis, flu-like symptoms, autism, and depressive and manic symptoms in patients with bipolar disorder. Some studies have indicated that NAC supplementation can decrease marijuana and nicotine cravings and help in treating many other psychiatric and neurological disorders.

[0003] The broad health benefits of active ingredients such as NAC, make it a supplement in high-demand, especially for elderly people. Studies have shown that taking a daily dose of NAC (as high as 7 grams) is beneficial for older patients. Yet, a solution of NAC in water is highly acidic (pH ~2) and has a strong and unpleasant aftertaste due to the presence of the thiol group (- SH) in NAC’s structure. In addition, the structural thiol group causes NAC to stink (egg odor) upon dissolution in water. For these reasons, it is very unpleasant to drink a solution of pure NAC in water. There are, however, some NAC products on the market in the form of pills or gelatin capsules that can be taken without experiencing the unwanted aftertaste or stink. But, these products provide only up to 1 g NAC per serving, making them unsuited for patients in need of high daily dose of NAC.

[0004] N-acetylcysteine (NAC) as an antioxidant can scavenge the hydroxyl radicals, hydrogen peroxide, and hypochlorous in the cells (Gillissen & Nowak, 1998) (Kelly, 1998) (Murphy & Lampe, 2018). This property is due to the high tendency of a thiol group to react with ·N02, C03·-, ·N3, and •OH (Samuni, Goldstein, Dean, & Berk, 2013) (Mallard, Ross, & Helman, 1998). NAC is applied for the treatment of respiratory diseases (Moldeus, Cotgreave, & Berggren, 1986), acetaminophen overdose (Heard & Green, 2012) (Rush worth & Megson, 2014), cancer (Van Zandwijk, Dalesio, Pastorino, De Vries, & Van Tinteren, 2000), metal toxicity, bronchitis, HIV/AIDS (Samuni, Goldstein, Dean, & Berk, 2013) (Lasram, Dhouib, Annabi, El Fazaa, & Gharbi, 2015), cardiovascular diseases (Rushworth & Megson, 2014), type-2 diabetes (Gibson, Neilson, Barrett, Winterbum, Sharma, MacRury, et al., 2009), schizophrenia, bipolar disorder, psychiatric disorders (Dean, Giorlando, & Berk, 2011), and chronic diseases (Buur, Diniz, Roderick, KuKanich, & Tegzes, 2013). (Young & II- Hwan, 1980) (Heard & Green, 2012) (Gibson, et al., 2009) (Samuni, Goldstein, Dean, & Berk, 2013) (Lasram, Dhouib, Annabi, El Fazaa, & Gharbi, 2015) (Dean, Giorlando, & Berk, 2011) (Rushworth & Megson, 2014) (Buur, Diniz, Roderick, KuKanich, & Tegzes, 2013) (Berk, Malhi, Gray, & Dean, 2013). The safest and best method of taking NAC with less adverse effects is orally (Slattery, Kumar, Delhey, Berk, Dean, Spielholz, et al., 2015) (Gray, Watson, Carpenter, & LaRowe, 2010).

[0005] Proper coating materials are usually used to protect sensitive compounds against unwanted reactions, oxidation, exposure to the light, losing quality, degradation, and evaporation. Further, the coating can increase the life span of sensitive ingredients and could be responsible for their release or delayed release in certain conditions. Extrusion coating, spray drying, fluidized- bed coating, spray cooling, coacervation, centrifugal extrusion, and melting method are some of the techniques for coating and encapsulation of materials while each of them has a certain application (Desai & Jin Park, 2005) (Fathi, Martin, & McClements, 2014) (Poornima & Sinthya, 2017) (Milanovic, Levic, Manojlovic, Nedovic, & Bugarski, 2011). Based on the application, the property and composition of core and coating materials, methods, and mechanism of release, size of particles can change from sub-micrometers to millimeters and their shapes change from spherical to the irregular shape. Coating materials not only should not react with the core materials but also should seal and protect the core and preferably release them under certain conditions (Desai & Jin Park, 2005) (Ball, 2008). [0006] Natural waxes h ave many applications in the food and pharmaceutical industries for coating the water-soluble materials and are permitted by the food and drug administration (FDA) and European Union (E901-903) because of their minor effects on materials and water-insoluble nature (hydrophobicity) (Milanovic, Levic, Manojlovic, Nedovic, & Bugarski, 2011) (Wang, Ando, Ishida, Ohtani, Tsuge, & Nakayama, 2001) (Kamble) (Cherukuri, Chau, Raman, & Orama, 1991) (Mellema, Van Benthum, Boer, Von Harras, & Visser, 2006). Beeswax, BW, (from honeybees), rice bran wax, RBW, candelilla wax, CanW, (from candelilla plant), and carnauba wax, CW, (from palm tree leaves) are examples of food-grade natural waxes for coating different food and drug compounds (Janjarasskul & Krochta, 2010). Carnauba wax that has the highest melting point among them, and has been used in the encapsulation of hydrophilic materials such as microencapsulation of valproic acid (Giannola, De Caro, & Severino, 1995), ketoprofen (Oliveira, Nascimento, & Lima, 2012), ascorbic acid (Uddin, Hawlader, & Zhu, 2001), drugs such as captopril and metformin hydrochloride (Nart, Beringhs, Franqa, de Espindola, Pezzini, & Stulzer, 2017), ethyl vanillin (Milanovic, Manojlovic, Levic, Rajic, Nedovic, & Bugarski, 2010), and potassium chloride crystals (Harris, 1981). Carnauba wax and beeswax were used for encapsulation of water-soluble colorant, toluidine blue dye (Mellema, Van Benthum, Boer, Von Harras, & Visser, 2006). Beeswax has been applied for encapsulation of fluorouracil and ftorafur (Giannola, Di, & De, 1993), rice barn wax has been used for coating chewing gums and candy (Buffa & CW, 1976), and candelilla wax has been used for phosphate fertilizer encapsulation (Navarro-Guajardo, Garcia-Carrillo, Espinoza-Gonzalez, Tellez-Zablah, Davila-Hernandez, Romero-Garcia, et al., 2018).

[0007] Previously, NAC was encapsulated by using poly(lactic-co-glycolic acid) (PLGA) and also inside the hexagonal MCM-41 and cubic MCM-48 (Murphy & Lampe, 2018) (Pathan, Solanki, & Patel, 2017). However, none of them were acceptable at the narrow range of food- grade materials. There are also reports of liposomal encapsulation of NAC using different phospholipids in which in all of them a toxic organic solvent such as chloroform has been used (Buonocore, Alipour, Omri, Pucaj, Smith, & Suntres, 2011) (Hamedinasab, Rezayan, Mellat, Mashreghi, & Jaafari, 2019) (Ourique, dos Santos Chaves, Souto, Pohlmann, Guterres, & Beck, 2014). All of these systems target low NAC loading for a specific use which is not supplement. SUMMARY

[0008] The present disclosure provides a stable nutritional product with a variety of health and pharmaceutical benefits that make it essential to be used as a high dose supplement. The present disclosure provides a method of solid phase wax coating for coating highly water-soluble active ingredient by using natural waxes and food grade oil and surfactants. The present disclosure provides an effective barrier for delayed and controlled release of an active ingredient dispersion into water and drinks with an improved mouthfeel.

[0009] Applicant surprisingly found that the present disclosure is capable of introducing a high dose of an active ingredient, such as NAC, to patients’ body without them having to experience the undesirable taste and smell. For example, for high dose NAC therapy, NAC loading of 60 wt% or higher is desired, and all of the materials must be safe for use as foods or supplements.

[0010] In a first aspect, a method for a ready to mix product may decrease an active ingredient release in water. A solid phase wax coating may be used for coating a highly water-soluble active ingredient by using natural waxes and food grade corn oil and surfactants. High active ingredient loading at least 25wt% can be obtained via wax coating of active ingredient granules produced via suspension granulation and/or other formats of solid active ingredients.

[0011] The active ingredient wax-coated particles were characterized by FT-IR, bright field microscopy, SEM, conductometry, and LC-MS, which confirm the high loading of active ingredient in the products. Microscopy and SEM images revealed the shape, morphology, and size of the particles, while active ingredient release profile in water from wax-coated particles was studied by conductometry. Solid phase wax coating can be used as for masking active ingredients with disagreeable mouthfeel.

[0012] In a further aspect, a method for solid phase wax coating of an active ingredient as a supplement may use natural food safe waxes, non-toxic organic solvent, and corn oil or other food grade oils as dispersion liquids. For example, NAC in different forms including powder, crystals, and spherical granules prepared via suspension granulation, may be used to prepare high loading products containing, for example, more than 55 wt% NAC. Morphological studies by SEM showed a uniform wax coating on the NAC in all forms used. NAC release studies in water by conductometry showed a control release in early stage of product dispersion in water.

[0013] The active ingredient may comprise at least one of N-acetylcysteine (NAC), an amino acid, a derivative of an amino acid, nicotinamide riboside, or a nicotinamide riboside derivative, ketones, vitamins, minerals. A wax selected from the group consisting of candelilla wax, carnauba wax, rice bran wax, beeswax, and mixtures thereof may be used. The surfactant used may be selected from the group consisting of dioctyl sulfosuccinate sodium salt (AOT), polysorbate 80 (Tween 80), sorbitan monooleate (Span 80), sorbitan monostearate (Span 60), and mixtures thereof.

[0014] An advantage of one or more embodiments provided by the present disclosure is that these high loading wax coated NAC particles as potential candidates for use as RTM in sachets for high dose NAC therapy.

[0015] Another advantage of one or more embodiments provided by the present disclosure is to provide a supplement containing high levels of active ingredients that are more easily consumable through dispersion into water and or other beverages.

[0016] Additional features and advantages are described herein and will be apparent from the following Figures and Detailed Description.

BRIEF DESCRIPTION OF THE FIGURES [0017] FIG. 1 shows a schematic of solid-phase NAC wax coating process.

[0018] FIG. 2 is a table of reaction conditions for the NAC powder- 80 mesh (P) coating with hydrophobic (natural waxes) materials.

[0019] FIG. 3 is a table of reaction conditions for the NAC crystals (C) coating with hydrophobic (natural waxes) materials.

[0020] FIG. 4 is a table of reaction conditions for the NAC granules (G) coating with hydrophobic (natural waxes) materials. The granules were prepared via phase separation granulation, previously.

[0021] FIG. 5 shows the NAC release profile of the 80mesh powder (P) samples coated with natural waxes by conductometry. The respective reaction conditions for these samples are as described in Fig. 2(a) P1-P4 and Fig. 2 (b) P5-P8.

[0022] FIG. 6 a and b shows NAC release profile for the NAC crystal (C) samples coated with natural waxes by conductometry. The respective reaction conditions for these samples are as described in: Fig 3(a) C1-C3, Fig.3(b) C4-C7; and in Fig.3(c) Release profile of C5 and C7 for 60 mm. [0023] FIG. 7 shows release profile for the NAC granules by conductometry; granules (G) have prepared previously via granulation experiment, and then wax coating with natural waxes. The respective reaction conditions for these samples are described in Fig. 4(a) G1-G3 and Fig. 4 (b) G4-G6.

[0024] FIG. 8 shows the comparison of release profile of G5 and G6 by conductometry; (solid line) release profile of particles from granulation experiment, (dotted line) release profile from the particles G5 or G6 after wax coating.

[0025] FIG. 9 shows the ATR-FTIR spectra of pristine NAC and wax-coated samples.

[0026] FIG. 10 shows microscopic images: Top: pristine NAC crystals and NAC crystal coating with different waxes (C1-C6). Bottom: Sample dispersed in water/glycerin [0027] FIG. 11 shows SEM photographs of pristine NAC crystals compared with some of NAC crystal wax-coated particles Cl,C4,C5Scale bars are 100 pm (top) and 20 pm (bottom), respectively.

[0028] FIG. 12 shows microscopic images of: Top: the granules NAC (prepared via phase separation granulation) coating with different waxes. Bottom: granulated NAC coated samples dispersed in water/glycerin

[0029] FIG. 13 shows SEM images of the granules NAC (prepared via phase separation granulation) coating with different waxes. A [NAC + HPMC + AOT : 80:15:5] and D [NAC + HPMC + AOT : 75:20:5] are NAC uncoated granules. B and C are granule A that coated with BW (Gl) and CW (G4), respectively. E is granule D that coated with CW (G6). Scale bars are 100 pm (top) and 20 pm (bottom), respectively.

[0030] FIG. 14 shows the gradient elution program of LC eluents.

[0031] FIG. 15 shows the dispersibility of samples in water during the conductometric measurement.

[0032] FIG. 16 shows ATR-FT-IR spectra of pristine NAC and pure hydrophobic coating materials (natural waxes).

[0033] FIG. 17 shows: Top: a) Selected Reaction Monitoring (SRM) chromatogram of pure NAC, b) mass spectrum of the pure NAC. Bottom: a) SRM chromatogram of C5 sample, b) mass spectrum of the C5 sample by LC-MS.

[0034] FIG. 18 shows images of NAC crystal before and after coating with CW (sample C6). [0035] FIG. 19 shows microscopic images of the NAC Powder, 80 mesh, (P) coating with natural waxes (Top: Powder, Bottom: powder in water-glycerin).

[0036] FIG. 20 shows SEM images of Pristine NAC powder, 80 mesh, (P); and NAC powder coated with different waxes (Sample P3, P4, P8).

DETAILED DESCRIPTION

[0037] The various aspects and embodiments according to the present disclosure, as set forth herein, are illustrative of the specific ways to make and use the invention and do not limit the scope of invention when taken into consideration with the claims and the detailed description. It will also be appreciated that features from aspects and embodiments of the invention may be combined with further features from the same or different aspects and embodiments of the invention.

[0038] As used in this detailed description and the appended claims, the singular forms “a,” “an” and “the” include plural referents unless the context clearly dictates otherwise. For example, reference to “an ingredient” or “a method” includes a plurality of such “ingredients” or “methods.” The term “and/or” used in the context of “X and/or Y” should be interpreted as “X,” or “Y,” or “X and Y.” Similarly, “at least one of X or Y” should be interpreted as “X,” or “Y,” or “both X and Y.” Similarly, the words “comprise,” “comprises,” and “comprising” are to be interpreted inclusively rather than exclusively. Likewise, the terms “include,” “including” and “or” should all be construed to be inclusive, unless such a construction is clearly prohibited from the context. However, the embodiments provided by the present disclosure may lack any element that is not specifically disclosed herein. Thus, a disclosure of an embodiment defined using the term “comprising” is also a disclosure of embodiments “consisting essentially of’ and “consisting of’ the disclosed components. “Consisting essentially of’ means that the embodiment or component thereof comprises more than 50 wt.% of the individually identified components, preferably at least 75 wt.% of the individually identified components, more preferably at least 85 wt.% of the individually identified components, most preferably at least 95 wt.% of the individually identified components, for example at least 99 wt.% of the individually identified components.

[0039] All ranges described are intended to include all numbers, whole or fractions, contained within the said range. As used herein, “about,” “approximately” and “substantially” are understood to refer to numbers in a range of numerals, for example the range of -10% to +10% of the referenced number, preferably -5% to +5% of the referenced number, more preferably -1% to +1% of the referenced number, most preferably -0.1% to +0.1% of the referenced number. Moreover, these numerical ranges should be construed as providing support for a claim directed to any number or subset of numbers in that range. For example, a disclosure of from 1 to 10 should be construed as supporting a range of from 1 to 8, from 3 to 7, from 1 to 9, from 3.6 to 4.6, from 3.5 to 9.9, and so forth. As used herein, wt% refers to the weight of a particular component relative to total weight of the referenced composition.

[0040] In a first aspect, a method of solid phase wax coating an active ingredient may comprise first dissolving a wax in a lipid to form a wax solution; then, adding to the wax solution the active ingredient and a surfactant to form a reaction mixture; and decreasing a temperature of the reaction mixture to form a composition comprising particles of the active ingredient. The particles may have a coating of the wax on the particles. The composition may comprise at least about 25 wt% of the active ingredient.

[0041] The composition may have a controlled release of the active ingredient of up to about 90 wt%, 85 wt%, 80 wt%, about 75 wt%, about 70 wt%, about 65 wt%, about 60 wt%, about 55 wt%, about 50 wt%, about 45 wt%, about 40 wt%, about 35 wt%, about 30 wt%, about 25 wt%, about 20 wt%, about 15 wt%, about 10 wt%, or about 1 wt% in water in about 5 minutes.

[0042] In an embodiment, the decreasing of the temperature of the reaction mixture may comprise decreasing the temperature of the reaction mixture to about room temperature. The method may further comprise decanting extra lipid from the reaction mixture when the temperature of the reaction mixture is about room temperature.

[0043] In an embodiment, the active ingredient may be a supplement. The active ingredient may be soluble in water and not soluble in the lipid. In another embodiment, the active ingredient may comprise at least one of N-acetylcysteine (NAC), an amino acid, a derivative of an amino acid, nicotinamide riboside, or a nicotinamide riboside derivative, ketones, vitamins, minerals. In an embodiment, the active ingredient may be in a form selected from the group consisting of powder, crystals, solid spherical granules, and combinations thereof.

[0044] In an embodiment, the wax used may be selected from the group consisting of candelilla wax, carnauba wax, rice bran wax, beeswax, and mixtures thereof. The surfactant is selected from the group consisting of dioctyl sulfosuccinate sodium salt (AOT), polysorbate 80 (Tween 80), sorbitan monooleate (Span 80), sorbitan monostearate (Span 60), and mixtures thereof. And, the lipid comprises corn oil. All materials used may be considered safe for the food or supplement.

[0045] In one embodiment, the composition formed by the method disclosed herein may comprise from about 25wt% to about 95 wt%,from about 30 wt% to about 95 wt%, from about 35wt% to about 95 wt%, from about 40 wt% to about 95 wt%, from about 45 wt% to about 95 wt%,from about 50 wt% to about 95 wt%, from about 55 wt% to about 90 wt%, from about 55 wt% to about 85 wt%, from about 55 wt% to about 80 wt%, from about 60 wt% to about 80 wt%, from about 65 wt% to about 80 wt%, from about 70 wt% to about 80 wt%, from about 75 wt% to about 80 wt%, from about 60 wt% to about 75 wt%, from about 65 wt% to about 75 wt%, from about 70 wt% to about 75 wt%, from about 60 wt% to about 70 wt%, or from about 65 wt% to about 70 wt% of the active ingredient.

[0046] In one embodiment, the composition formed by the method disclosed herein may comprise at least about 25 wt% of the active ingredient. In another embodiment, the composition formed by the method comprised at least 50 wt% of the active ingredient. In a preferred embodiment, the composition formed by the method comprised at least 60 wt% of the active ingredient.

[0047] In an embodiment, the decreasing of the temperature of the reaction mixture may comprise decreasing the temperature of the reaction mixture about 5 °C per 30 minutes to reach about 25 °C.

[0048] In an embodiment, the active ingredient may be prepared by a method of encapsulating an active ingredient, the method comprising: providing an aqueous solution comprising the active ingredient, a gum, and a surfactant in water; adding to the aqueous solution a coating solution to form a transparent solution, mixing the transparent solution into a liquid lipid; and removing the water and the volatile solvent to form a composition comprising the solid spherical granules containing the active ingredient, wherein the solid spherical granules each comprise an inner core comprising the active ingredient, the gum, and the surfactant.

[0049] In an embodiment, the solid spherical granules of the active ingredient may comprise about 25 wt%, about 20 wt%, about 19 wt%, about 18 wt%, about 17 wt%, about 16 wt%, about 15 wt%, or about 10 wt% hydroxypropyl methylcellulose (HPMC) or carboxymethylcellulose (CMC). In another embodiment, the removing of the water may generate the solid spherical granules.

[0050] In another aspect, the method/process/steps disclosed herein can be used for decreasing solubility of an active ingredient in water and/or the mouth of a subject consuming the active ingredient.

[0051] In another aspect, the method/process/steps disclosed herein can be used for preparing a composition with controlled release of an active ingredient in the composition.

[0052] In a further aspect, the method/process/steps disclosed herein can be used for masking an undesirable taste of an active ingredient.

[0053] EXAMPLES

[0054] The following non-limiting examples are experimental examples supporting one or more embodiments provided by the present disclosure.

[0055] Example 1 : A procedure for active ingredient solid-phase wax coating [0056] Fig. 1 shows the process of solid-phase NAC wax coating.

[0057] A jacketed glass reactor with proper mixer was used, equipped with a water bath circulator for temperature adjustment. CW as a hydrophobic coating was added into the reactor containing corn oil at 70 to 80 °C. After complete dissolution of wax in corn oil, the surfactant was added into the reactor while it was stirring. In this step, NAC powder, crystals, or granules was added into the reactor while stirring at 400 rpm using a mechanical mixer. By slowly decreasing the temperature of the reaction (5 °C per 30 min to reach 25 °C), a film of wax was formed on the surface of the NAC particles. After the reaction reached room temperature, the extra corn oil was decanted and samples were vacuum filtered to dry.

[0058] For the preparation of the NAC granules used for wax coating, at first step, a concentrated and viscose aqueous solution of NAC that contains gum and a surfactant at 70 °C, was added to corn oil while stirring at 55 °C. The suspension continued stirring at 55 °C for 15 h (overnight) and then the temperature increased to 70 °C for 2 more hours to ensure complete water removal. Then the stirring stopped and the extra corn oil was removed by decantation, and samples were vacuum filtered and washed with cold hexanes before being dried.

[0059] NAC crystals and NAC powder (80 mesh) are products sourced from Wuhan Grand Hoyo Co. Ltd, China. Candelilla wax from Sigma-Aldrich (CanW, melting point 68-72 °C), carnauba wax from Sigma-Aldrich (CW, melting point 82 °C, No.1 yellow, refined), rice bran wax from Nutley's Kitchen Gardens (RBW, melting point 79-85 °C), beeswax from Strahl & Pitsch, Inc., (BW, DR-101, melting point 62-65 °C), xanthan gum from TIC Gums, carboxymethyl cellulose (CMC) from Sigma (low viscosity, 50-200 mPa s, 4% in water), Dioctyl sulfosuccinate sodium salt or AOT 96% from VWR, hydroxypropyl methylcellulose (HPMC) from Fisher (40- 60 mPa s, 2% in water), sorbitan monostearate or Span 60 from TCI America (saponification value: 145 to 156), sorbitan monooleate or Span 80 from Sigma-Aldrich (saponification value: 145 to 160), hexanes from Fisher (>98.5%, Certified ACS, Fisher), corn oil (from local market), Milli-Q and DI water were used for analyses and experiments, respectively. Formic acid (FA 98%) from Sigma-Aldrich, and acetonitrile from Sigma-Aldrich (HPLC grade, >99.9%) were used without any further purification.

[0060] Example 2: Methods of Characterization

[0061] The active ingredient release profile in water by conductometry. The conductivity of samples was measured using Metrohm 856 Conductimeter 856 Conductivity measuring module, equipped with a 5-ring probe electrode (0.7 constant, conductivity range of 5- 20 mS/cm). A 100 ml beaker (OD: 5 cm, ID: 4.5 cm, H: 7.5 cm) was chosen for NAC release. Samples were added to DI water at 60 s while stirring at 500 RPM using magnetic stirring bar (2.0 x 0.7 cm) at ambient temperature. For all samples, a specific amount is calculated in order to provide 2.5 w% of NAC in water, theoretically. The conductometric information was recorded using software Tiamo, Version 2.5 for 600 s or more in few cases. In addition, pure NAC at different concentrations (0.25, 0.5, 0.75, 1.0, 1.25, 1.5, 1.75, 2.0, 2.25, and 2.5 w%) were used to prepare a calibration curve of conductivity vs. concentration.

[0062] ATR-FTIR spectroscopy analysis. In order to characterize the wax-coated NAC particles, Shimadzu IRAffinity-lS FTIR spectrophotometer was used, equipped with attenuated total reflectance (ATR). Samples were scanned 64 times in the selected spectral range from 400 to 4000 cm^-1 with the resolution of 2 cm^-1. The data was analyzed by LabSolution IR software. [0063] LC-MS analysis. In order to determine NAC loading in the products, LC (Agilent 1100 series) equipped with mass spectrometer was used. Luna Omega LC column (Phenomenex, 100 x 4.6 mm, 3 pm, Polar Cl 8100 A) was used at reverse-phase chromatography for separation. LC eluents included solution A: Di-water (formic acid 0.1 v/v%) and solution B: acetonitrile under gradient elution (Fig. 14 supporting information). The flow rate and injection volume were 0.3 mL min ¹ and 10 pL, respectively. The column temperature was kept at room temperature and overall run time of each sample was 12 minutes. The mass spectrometer (Finnigan LTQ mass spectrometer) equipped with an electrospray interface (ESI) in positive electrospray ionization mode was used for the mass spectral data acquisition of NAC. The optimized parameters were including sheath gas flow rate at 20 arbitrary unit, spray voltage set at 4.00 kV, the capillary temperature at 350 °C, capillary voltage at 41.0 V, and tube lens voltage set at 125.0 V.

[0064] Microscopy and SEM image acquisition. The visualization of NAC particles was done by LEICA DFC 3000 G bright field microscope. Samples were put on the microscope slide and a 50:50 solution of glycerin in water was added to wet the samples and provide the contrast for core shell identification. The photos of samples were taken before and after wetting. To observe the morphology of NAC coated particles, scanning electron microscopy (SEM) micrographs was used for some of the selected samples from NAC powder, NAC crystals, and NAC granules. A Zeiss Gemini 500 Field Emission SEM was used. Before being mounted on the SEM machine, all of the samples have been coated with an ultra-thin gold layer using a sputter coater.

[0065] Example 3: NAC release profile of the wax-coated NAC samples by conductometry

[0066] NAC is a small molecule with very high water solubility (20 w% at room temperature) with many health benefits. Despite its great advantages, using pure NAC directly in water for drinking is almost impossible due to its high acidity, unpleasant smell, and sour and bitter taste that produce a very long undesired aftertaste. Coating is one of the effective ways to decrease the solubility of NAC in the water and mouth. Three types of solid NAC were used as starting material for the wax coating technique, including NAC powder 80 mesh (P), NAC crystals, 350-1000 pm (C), and NAC granules from granulation experiments (G). Compositions and reaction conditions of these three different classes of wax coating are presented in Fig. 2, 3, and 4. One of the major benefits of the NAC solid phase coating is that there is no need for preparation of NAC solutions and therefore, no extra time and energy is needed for removing water to form the particles.

[0067] NAC is a highly polar small molecule that easily dissolves in water and subsequently dissociates, which raises the level of ions in the water. The dissolution profile of NAC and/or its release can be followed by conductometry. The higher release of NAC, the higher value of conductivity. Conductivity is a precise analytical tool for measuring the release of NAC from products into DI water (Fig. 15). Fig. 5, 6, and 7, represent the conductivity results of NAC release in three graphs. In all of conductivity graphs, the conductivity profile of “2.5 w% of pure NAC” (black broken line) presented for comparison with the NAC release from wax-coated products. From the application point of view, up to 30% NAC release in water in 5 min is acceptable (intersection of 30% NAC release and 5 min after addition lines). For samples that release NAC lower than this level, the astringency, taste, and smell of a 2.5 w% dispersion is acceptable for drinking.

[0068] Based on NAC release profiles on Fig. 5 and 6, CW (P8) gives the lowest NAC release (highest coating efficiency) via solid-phase wax-coating, however, BW and CanW in P4 and P2, respectively, demonstrate acceptable results, too.

[0069] The NAC crystals used for wax coating experiments (Fig. 6a), were filtered to be in the range of 350-1000 pm size. In the case of C7, the sample was not washed with hexanes, and corn oil was removed only by vacuumed filtration (Fig. 6a), and it shows a very low release of NAC. On the other hand, C5, which had the same composition as C7, was washed by hexanes, and still shows acceptable NAC release. As can be seen from Fig. 6a, washing by hexanes results in increased NAC release, most probably because it can create some cracks on the coating materials on NAC crystals (it will discuss later based on the SEM micrographs).

[0070] Due to slowed NAC releasing from C5 and C7, both of these products were analyzed for a longer time for conductivity measurement (60 min) to see if they contain the claimed NAC percentage in Fig. 3. Fig. 6b presents the release profile of C5 and C7 over 60 min of measurement. As can be seen in Fig. 6b, the conductivity of samples C5 and C7 increased gradually with time meaning that NAC release gradually from these formulations.

[0071] Fig. 7 represents the NAC release from wax-coated NAC granules. NAC granules prepared in suspension granulation experiment without any hydrophobic coating, and therefore, they need further coating in order to retain NAC. Advantages of the NAC granule coating is that these particles are spherical and can be made with different sizes as need. However, they will produce in two steps including dissolution in water and removing water. Also, NAC loading is typically lower in granules formulations (Fig. 4) as gums are used as structuring for the granulation step.

[0072] Fig. 8 demonstrates the conductivity of NAC, for G5 and G6 samples before and after wax coating. As it can be seen in this Figure, although the amount of the samples normalized to have the same gram of NAC, both samples showed significant decrease in NAC release after wax coating. Sample G6 that contains 20 wt% HPMC shows interesting results indicating a balance between the gum and the CW amount can result in very good release profile. [0073] Example 4: Structural identification of a wax coated active ingredient particles by ATR-FTIR

[0074] An ATR-FTIR spectra of the starting materials and products were prepared and compared in Fig. 16, and Fig. 9, respectively. NAC shows the N-H stretching vibration at 3370 cnT¹ (Pavia, Fampman, Kriz, & Vyvyan, 2008), a specific sharp peak at 2550 cnT¹ which is related to the free S-H stretching (Du, Fiu, Zhai, Huang, Wei, Zhang, et al., 2019; Pathan, Solanki, & Patel, 2017; Pavia, Fampman, Kriz, & Vyvyan, 2008), the peak of the carbonyl group at 1715 cnT ¹ (Hamedinasab, Rezayan, Mellat, Mashreghi, & Jaafari, 2019), the N-H bending at 1530 cm ¹ (Pavia, Fampman, Kriz, & Vyvyan, 2008), and another peak at 535 cm^-1 related to stretching of carboxyl groups (Du, et al., 2019). The ATR-FTIR spectra of the products show the distinct peaks at 3370 and 2550 cm ¹ related to the N-H and S-H bonds, respectively, which proved the presence of NAC in the particles. Moreover, peaks at 2915 and 2850 cm ¹ are related to the C-H (aliphatic) bond of the natural waxes (Pavia, Fampman, Kriz, & Vyvyan, 2008). The peaks of the carbonyl group of the particles are broader with a small shoulder, which is related to the carbonyl group of both NAC and waxes in the products. These results confirmed the presence of the NAC in the products which is further confirmed by FC-MS data.

[0075] Example 5: Determination of an active ingredient loading by FC-MS

[0076] The formulation designed to have 60 wt% or higher of NAC loading (except G5 and

G6), Fig. 2-4. To determine the experimental NAC loading of the products, methods were developed based on FC-MS. A typically Selected Reaction Monitoring (SRM) chromatogram and mass spectrum of pure NAC and C5 were presented in Fig. 17. The experimental NAC loading calculated based on FC-MS analysis, are reported in Fig. 2-4. As can be seen in Fig. 2-4, for majority of the samples, the theoretical and experimental NAC loading are in good agreement. However, for some of the samples the experimental NAC loading is higher than theoretical value, which is likely because not all of the wax that is dissolved in oil was used for the coating and a lower amount of the wax deposited on the samples.

[0077] Example 6: Morphology of the wax coated active ingredient particles [0078] Fig. 18 shows a photo of NAC crystals before (left) and after (right) CW coating (sample C6). The off-white coating is observed on the crystal surfaces. These particles are not sticky therefore, they do not agglomerate. The shape and size of the product is determined and correspond to the starting crystals. Fig. 10 presents the microscopy images of wax-coated NAC crystals before and after water/glycerin addition. It is clearly seen that a film of the wax formed on the surface of crystals upon coating. The SEM micrographs of pristine NAC crystals and selected samples of wax-coated NAC crystals are presented in Fig. 11.

[0079] Microscopy and SEM images of the wax-coated NAC powder particles are presented in Fig. 19 and 20, respectively, which show the irregular and agglomerated particles due to the small size of the NAC powder (80 mesh).

[0080] Fig. 12 and 13 show the microscopy and SEM images of some of wax-coated granulated samples, respectively. The microscopic images in Fig. 12 are photos of the samples before and after applying the water/glycerin medium and they were taken to show the microscopic behavior of the wax-coated particles before and after exposure to water/glycerin. In all of the studied sample, the core shell structure after wax coating is clearly observed.

[0081] Fig. 13 shows the SEM micrographs for some of the granulated NAC samples before and after wax-coating. It is obvious that there are some NAC crystals on the surface of the granulated particles (due to the recrystallization) before wax coating (Fig. 13 A and D), which cannot be seen after the coating, showing the efficiency of the process. In addition, it can be seen that these granulated particles are spherical and can be produced in desired size.

[0082] It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present subject matter and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.

Claims

1. A method of solid phase wax coating an active ingredient, the method comprising: dissolving a wax in a lipid to form a wax solution; adding to the wax solution the active ingredient and a surfactant to form a reaction mixture; decreasing a temperature of the reaction mixture to form a composition comprising particles of the active ingredient, the particles having a coating of the wax on the particles, wherein the composition comprises at least about 25 wt% of the active ingredient and has controlled release of the active ingredient of up to about 90 wt% in water in 5 minutes.

2. The method of claim 1 wherein the decreasing of the temperature of the reaction mixture comprises decreasing of the temperature of the reaction mixture to about room temperature, and the method further comprises decanting extra lipid from the reaction mixture when the temperature of the reaction mixture is about room temperature.

3. The method of claim 1, wherein the active ingredient is a supplement.

4. The method of claim 1 , wherein the active ingredient is soluble in water and not soluble in the lipid.

5. The method of claim 1, wherein the active ingredient comprises at least one of N- acetylcysteine (NAC), an amino acid, a derivative of an amino acid, nicotinamide riboside, or a nicotinamide riboside derivative, ketones, vitamins, minerals.

6. The method of claim 1 , wherein the wax is selected from the group consisting of candelilla wax, carnauba wax, rice bran wax, beeswax, and mixtures thereof.

7. The method of claim 1, wherein the surfactant is selected from the group consisting of dioctyl sulfosuccinate sodium salt (AOT), polysorbate 80 (Tween 80), sorbitan monooleate (Span 80), sorbitan monostearate (Span 60), and mixtures thereof.

8 The method of claim 1, wherein the lipid comprises vegetable oils, such as corn oil.

9. The method of claim 1 , wherein all materials used are at least one of food safe, supplement safe or generally recognized as safe (GRAS) for consumption.

10. The method of claim 1, wherein the composition comprises from about 50 wt% to about 90 wt% of the active ingredient.

11. The method of claim 10, wherein the composition comprises at least about 60 wt% of the active ingredient.

12. The method of claim 1, wherein the composition releases at least about 50 wt% of the active ingredient in water in 5 minutes.

13. The method of claim 1, wherein the active ingredient is in a form selected from the group consisting of powder, crystals, solid spherical granules, and combinations thereof.

14. The method of claim 12, wherein the active ingredient is in the form of solid spherical granules prepared by a method of encapsulating an active ingredient, the method comprising: providing an aqueous solution comprising the active ingredient, a gum, and a surfactant in water.

15. The method of claim 13, wherein the solid spherical granules of the active ingredient comprise up to 20 wt% or up to 30 wt.% of hydroxypropyl methylcellulose (HPMC) and/or carboxymethylcellulose (CMC).

16. The method of claim 13, wherein the removing of the water generates the solid spherical granules.

17. The method of claim 1 , wherein the decreasing of the temperature of the reaction mixture comprises decreasing the temperature of the reaction mixture about 5 °C per 30 minutes to reach about 25 °C.

18. A method of preparing a composition with controlled release of an active ingredient in the composition, the method comprising: dissolving a wax in a lipid to form a wax solution; adding to the wax solution the active ingredient and a surfactant to form a reaction mixture; decreasing a temperature of the reaction mixture to form the composition comprising particles of the active ingredient with a coating of the wax, wherein the composition comprises at least about 50 wt% of the active ingredient and has controlled release of the active ingredient of up to about 80 wt% in water in 5 minutes.

19. The method of claim 17, wherein the decreasing of the temperature of the reaction mixture comprises decreasing the temperature of the reaction mixture about 5 °C per 30 minutes to reach about 25 °C.

20. A process of decreasing solubility of an active ingredient in water and/or the mouth of a subject consuming the active ingredient, the method comprising providing the active ingredient in the composition prepared by the method of claim 1.

21. A method of masking an undesirable taste of an active ingredient, the method comprising: dissolving a wax in a lipid to form a wax solution; adding to the wax solution the active ingredient and a surfactant to form a reaction mixture; decreasing a temperature of the reaction mixture to form the composition comprising particles of the active ingredient with a coating of the wax, wherein the composition comprises at least about 50 wt% of the active ingredient and has controlled release of the active ingredient of up to about 80 wt% in water in 5 minutes.

22. The method of claim 20, wherein the decreasing of the temperature of the reaction mixture comprises decreasing the temperature of the reaction mixture 5 °C per 30 minutes to reach 25 °C.