1. Introduction
Creatine monohydrate (CM), with the chemical formula C4H9N3O2H2O, is a widely used organic compound that plays a critical role in energy metabolism, particularly in muscles and the brain. It is most commonly known for its applications in the sports nutrition industry, but its versatility has led to expanding use in a wide range of sectors, including food additives, cosmetics, pharmaceuticals, animal feed, and beverages.
From a chemical engineering perspective, creatine monohydrate is a highly stable and effective compound that provides benefits in energy storage and performance enhancement. This article explores the chemical properties, industrial production methods, and diverse applications of creatine monohydrate.
2. Chemical Properties of Creatine Monohydrate
Creatine monohydrate is a natural nitrogenous compound primarily found in skeletal muscles and brain tissue. It functions as an energy reservoir by replenishing adenosine triphosphate (ATP), the primary energy carrier in cells.
Chemical Structure and Formula:
- Chemical Name: Creatine monohydrate
- CAS Number: 6020-87-7
- Molecular Formula: C4H9N3O2H2O
- Molecular Weight: 149.15 g/mol
- Appearance: White crystalline powder
- Solubility: Slightly soluble in water (14 g/100 mL at 20°C)
- Melting Point: Approximately 253°C (decomposes)
Creatine monohydrate is composed of a creatine molecule (C4H9N3O2) and a single water molecule (H2O). The creatine molecule itself consists of an amino acid structure with a guanidino group attached to an acetate backbone, making it highly polar and readily available for hydrolysis in aqueous environments.
Key Chemical Properties:
- Solubility: Creatine monohydrate exhibits low solubility in water, which influences the dissolution rates in formulations.
- pKa: The guanidino group of creatine monohydrate has a pKa of approximately 12.6, making it weakly basic at physiological pH.
- Stability: Creatine monohydrate is relatively stable under normal conditions, though it can degrade over time to creatinine, especially in aqueous solutions and under elevated temperatures.
- Hygroscopicity: The monohydrate form is hygroscopic, meaning it absorbs water from the surrounding environment, which can lead to changes in weight and volume.
3. Industrial Production of Creatine Monohydrate
3.1. Synthesis Routes
The production of creatine monohydrate is primarily based on synthetic processes, with two main routes being used in industrial production: the Sarcosine route and the Cyanamide route.
3.2. Sarcosine Route (Most Common Industrial Process)
This is the most widely adopted synthetic route for creatine monohydrate. The process involves the reaction between cyanamide and sarcosine, followed by crystallization and dehydration to form the monohydrate.
Process Flow:
- Step 1: Formation of Guanidinoacetate
Sarcosine (N-methylglycine) reacts with cyanamide to form guanidinoacetate.
Sarcosine(CH3NCH2COOH)+Cyanamide(CH2N2)→Guanidinoacetate(NH2C(NH)CH2COOH)\text{Sarcosine} (CH3NCH2COOH) + \text{Cyanamide} (CH2N2) → \text{Guanidinoacetate} (NH2C(NH)CH2COOH)Sarcosine(CH3NCH2COOH)+Cyanamide(CH2N2)→Guanidinoacetate(NH2C(NH)CH2COOH)
- Step 2: Methylation
Guanidinoacetate undergoes methylation using methyl iodide to form creatine.
Guanidinoacetate+CH3I→Creatine(NH2C(NH)CH2COOH)\text{Guanidinoacetate} + \text{CH3I} → \text{Creatine} (NH2C(NH)CH2COOH)Guanidinoacetate+CH3I→Creatine(NH2C(NH)CH2COOH)
- Step 3: Formation of Creatine Monohydrate
Creatine is then reacted with water to form creatine monohydrate, followed by crystallization under controlled conditions to isolate the monohydrate form.
Creatine+H2O→Creatine Monohydrate\text{Creatine} + H2O → \text{Creatine Monohydrate}Creatine+H2O→Creatine Monohydrate
Advantages:
- High purity product can be achieved.
- The process can be scaled up effectively for industrial production.
Disadvantages:
- Requires careful control of reaction conditions, particularly during crystallization and drying.
3.3. Cyanamide Route (Less Common)
Another method is based on the reaction of cyanamide with glycine to form guanidinoacetate, which then undergoes methylation to form creatine. This method is less commonly used due to its lower yield and higher cost.
4. Applications of Creatine Monohydrate
Creatine monohydrate has diverse applications across various industries. Below, we explore its use as an additive in food, cosmetics, feed, beverages, and pharmaceuticals, as well as its role in health supplements.
4.1. Food and Beverage Additives
In the food and beverage industry, creatine monohydrate is primarily used in sports nutrition and functional foods.
- Energy Supplements: Creatine is added to energy drinks, protein powders, and sports beverages to enhance athletic performance, muscle endurance, and recovery. Creatine is often included in formulations alongside other ingredients such as beta-alanine or branched-chain amino acids (BCAAs).
- Functional Foods: Creatine can be incorporated into nutritional bars, fortified snacks, and meal replacement products. It helps provide an extra source of energy during intense physical activity, especially for athletes and fitness enthusiasts.
- Dosage Forms: Creatine monohydrate is used in tablet, capsule, powder, or liquid forms for easy consumption, with precise dosages to optimize athletic performance.
Regulatory Status:
Creatine is generally regarded as safe (GRAS) by the FDA for use in food supplements and beverages, with recommended daily doses usually ranging from 3 to 5 grams per day.
4.2. Cosmetic and Personal Care Products
Creatine is gaining popularity in cosmetic formulations due to its potential benefits for skin health. It is mainly used in anti-aging and skin rejuvenation products.
- Surface-active agents: Creatine is used in cosmetic formulations as an emulsifier and conditioning agent. Its ability to stabilize emulsions and improve the texture and feel of formulations makes it ideal for inclusion in moisturizers, shampoos, and skin lotions.
- Anti-aging and skin repair: Creatine’s role in energy metabolism extends to the skin, where it supports the synthesis of collagen and improves skin hydration, elasticity, and overall appearance. Anti-wrinkle creams and serums often contain creatine as a key ingredient.
- Hair Care: Creatine is sometimes used in hair care products to improve hair strength and shine by enhancing the structural integrity of hair fibers.
4.3. Animal Feed Additives
Creatine monohydrate is commonly added to animal feed, particularly for livestock, poultry, and aquaculture, as it supports growth and enhances performance.
- Muscle Growth and Meat Yield: Creatine is included in animal feed formulations to enhance muscle growth and feed conversion efficiency, particularly in animals raised for meat production (e.g., pigs, chickens, and fish).
- Performance in Aquaculture: In aquaculture, creatine is used to improve growth rates and muscle development in fish and shellfish, leading to higher yields in farming operations.
4.4. Pharmaceutical and Healthcare Industry
Creatine monohydrate plays a significant role in pharmaceuticals and healthcare supplements.
- Muscle Wasting Diseases: Creatine is used as a nutritional supplement for individuals suffering from muscle-wasting diseases such as muscular dystrophy, ALS, and Parkinson’s disease. It helps mitigate the loss of muscle mass and improve strength and mobility.
- Neurological Conditions: There is emerging evidence supporting creatine’s potential benefits in treating neurodegenerative diseases, including Alzheimer’s and Parkinson’s disease. Creatine’s ability to enhance ATP production could provide energy to damaged neurons and support brain function.
- Bone Health: Some studies suggest that creatine supplementation may have a positive effect on bone density and bone mineral content, especially in elderly individuals at risk of osteoporosis.
4.5. Health Supplements
Creatine monohydrate remains one of the most popular and widely used sports supplements globally
Specifications
| Parameter | Typical specification |
|---|---|
| Appearance | White crystalline powder |
| Assay | 99% min |
| Loss on drying | 12.5% max (monohydrate) |
| Heavy metals | 10 ppm max |
| CAS number | 6020-87-7 |
| Molecular formula | C4H9N3O2.H2O |
| Molecular weight | 149.15 g/mol |
Creatine monohydrate is the hydrated form that is standardised for supplement and food use; the loss-on-drying value reflects the bound water of the monohydrate.
Frequently Asked Questions about Creatine Monohydrate
What is creatine monohydrate used for?
It is used mainly in sports nutrition and food supplements, and also in animal feed, cosmetic and pharmaceutical applications.
Why is the monohydrate form used?
The monohydrate is the most studied and most stable commercial form of creatine, and it is standardised on assay and loss on drying.
How should creatine monohydrate be stored?
Cool, dry and tightly sealed, away from moisture and heat; the powder is hygroscopic and can cake if exposed to humidity.
Where can I buy creatine monohydrate?
PolyBlueChem supplies creatine monohydrate (CAS 6020-87-7) with COA and MSDS.
Related Products and Further Reading
- Creatine monohydrate (CAS 6020-87-7) – specifications, packaging and quotation.
- Creatine monohydrate for sports nutrition: dosage and safety.
- How to buy creatine monohydrate: specs, COA and grades.
- Creatine monohydrate vs other creatine forms.
Creatine Monohydrate Specifications
Creatine monohydrate (CAS 6020-87-7) is the hydrate of creatine, the most widely used form of the ingredient. The table below summarises the properties buyers and formulators most often need.
| Property | Value |
|---|---|
| Chemical name | Creatine monohydrate; (2-(carbamimidoyl-methylamino)acetic acid monohydrate) |
| CAS Registry Number | 6020-87-7 (monohydrate); 57-00-1 (anhydrous creatine) |
| Molecular formula | C4H9N3O2 · H2O |
| Molecular weight | About 149.15 g/mol (monohydrate) |
| Appearance | White crystalline powder |
| Solubility | Limited in water (roughly 13 g/L at 20 °C); solubility improves with temperature |
| Water content | About 12% water of crystallisation in the monohydrate |
| Typical purity | 99% min (assay) in commercial food / sports-nutrition grades |
The water of crystallisation is the key difference between the monohydrate and anhydrous forms, and it is the reason the monohydrate is the standard commercial article: it is stable, free-flowing and cost-effective, and it reconstitutes predictably.
Grades and Applications
| Grade | Typical use | Key specification points |
|---|---|---|
| Sports-nutrition grade | Powders, capsules, functional drinks | Assay, moisture, particle size, heavy metals |
| Food-grade | Fortified foods and beverages | Assay and food-safety limits |
| Micronised grade | Ready-to-mix powders | Reduced particle size for faster dispersion |
| Pharmaceutical / research grade | Formulation R&D and reference use | Documented purity and identity |
Micronisation is a common value-add: reducing the particle size improves dispersion and mouthfeel in ready-to-mix products, which is why micronised grades command a premium in the sports-nutrition market.
How Creatine Monohydrate Is Produced
Creatine is made synthetically. The two main routes are:
- From sarcosine and cyanamide. Sarcosine reacts with cyanamide to form creatine, which is then crystallised as the monohydrate. This is the classical synthetic route.
- From creatinine. Creatinine is hydrolysed under controlled conditions to creatine, which is isolated and crystallised as the monohydrate.
In both routes the final step is crystallisation, which sets the particle size, the moisture content and the flow properties of the finished powder. Purity, moisture and heavy-metal content are the parameters that define a commercial lot.
Creatine Monohydrate vs Other Creatine Forms
The market offers several creatine forms, and most of the claims made for the newer ones are commercial rather than well-evidenced. What matters technically is the creatine content per gram of powder, the solubility, and how fast the material converts to creatinine in solution – because creatinine is inactive. The table below compares the forms on those points.
| Form | Creatine content | Solubility | Stability in solution | Relative cost | Evidence position |
|---|---|---|---|---|---|
| Creatine monohydrate (CAS 6020-87-7) | About 87.9% (the balance is water of crystallisation) | Approx. 13-14 g/L at 20 deg C | Dry form stable; in solution it cyclises to creatinine, faster at lower pH | Lowest | The form used in the great majority of published studies |
| Anhydrous creatine (CAS 57-00-1) | 100% | Slightly higher than the monohydrate | Stable dry, but hygroscopic; solution behaviour similar | Higher | No established advantage over the monohydrate when compared per gram of creatine |
| Creatine hydrochloride | Around 78% | Higher solubility, dissolves more readily | Less stable in solution – converts to creatinine faster | Higher | Improved uptake claims are not supported by controlled human data |
| Creatine malate | Around 60% depending on stoichiometry | Moderate | Moderate | Higher | No independent evidence of superiority |
| Buffered creatine (pH-adjusted) | Around 70% | Moderate | Higher pH slows conversion | Higher | Degradation claims are largely commercial; head-to-head data are thin |
| Creatine nitrate | Lower, varies by product | High | Moderate | Higher | Also delivers nitrate; evidence for the combination is limited |
Two practical consequences follow. First, comparing products on “grams per serving” rather than on creatine content per gram flatters the anhydrous and buffered forms for no functional reason. Second, micronised monohydrate is still monohydrate – micronisation changes particle size and therefore dispersion and mouthfeel, not the chemistry, and it is a legitimate quality grade rather than a different molecule.
What to specify on a creatine purchase order
These are the parameters that decide whether two lots of “99.5% creatine monohydrate” behave the same on a production line.
| Parameter | Typical specification | Why it matters |
|---|---|---|
| Assay (creatine monohydrate, on dried basis or as-is) | 99.5% minimum, with the basis stated | Assay quoted on a different basis is not comparable between suppliers |
| Water content | Around 12% for the monohydrate (it is part of the crystal) | A “drier” lot is not better – it means the material is not the monohydrate |
| Creatinine content | Low, with a limit agreed on the COA | Creatinine is the degradation product and is inactive; a high figure points to heat or pH damage in processing |
| Heavy metals (Pb, As, Hg, Cd) | Limits per the grade claimed (food, feed or pharmaceutical) | This is the parameter that decides whether a lot can enter a food or feed chain at all |
| Particle size / micronised grade | Agreed mesh or micron range, e.g. 200 mesh or a defined D50 | Drives dispersion in a shaker, a premix or a capsule line |
| Microbiology | Total plate count, yeast and mould, E. coli and Salmonella absent | Required for any food or feed application |
| Residual solvents and process aids | Declared per the route used | Relevant when the buyer’s own specification or market rules require it |
Packaging, documentation and grades
| Item | Typical supply | Confirm before ordering |
|---|---|---|
| Packaging | 25 kg paper sacks or cartons with PE liner; bulk bags on request | Whether your handling keeps the liner sealed – creatine picks up moisture and cakes |
| Grade | Food grade, feed grade or pharmaceutical grade, plus micronised variants | That the grade matches the market you are selling into, not just the assay |
| Documentation | Batch COA (assay, water, creatinine, heavy metals, microbiology) plus SDS and, where applicable, allergen and GMO statements | That measured values – not “conforms” – appear on the COA |
| MOQ and lead time | Confirmed per grade, packing and destination | That the delivery window fits your production or contract schedule |
| Sample | Sample from the exact grade for trial | Run an assay and a particle-size check on arrival |
Quality and Sourcing Considerations
| Consideration | What to confirm |
|---|---|
| Assay | 99% min, stated on the COA |
| Moisture / water of crystallisation | Consistent with the monohydrate form |
| Particle size | Standard or micronised, matched to the end product |
| Heavy metals | Within food / sports-nutrition limits |
| Documentation | COA and SDS; food-grade documentation where relevant |
Because creatine monohydrate is a high-volume sports-nutrition ingredient, lot-to-lot consistency of assay, moisture and particle size matters as much as the headline purity figure.
Frequently Asked Questions about Creatine Monohydrate
What is the difference between creatine monohydrate and creatine?
Creatine monohydrate (CAS 6020-87-7) is creatine with one molecule of water of crystallisation. It is the standard commercial form; anhydrous creatine (CAS 57-00-1) contains no water of crystallisation.
What is creatine monohydrate used for?
Mainly as an ingredient in sports nutrition and functional foods, and in supplement and pharmaceutical formulation. It is also used as a research material.
How is creatine monohydrate made?
Synthetically – typically from sarcosine and cyanamide, or by hydrolysis of creatinine – followed by crystallisation to the monohydrate.
What purity is supplied?
Commercial food and sports-nutrition grades are typically 99% minimum assay, with controlled moisture, particle size and heavy-metal content.
What is micronised creatine monohydrate?
It is the same material milled to a smaller particle size so that it disperses more readily in ready-to-mix powders. It is a particle-size grade, not a different chemical.
How should creatine monohydrate be stored?
Dry, sealed and away from moisture and heat. The monohydrate is stable under normal storage, but packaging integrity matters because the material is hygroscopic.
How do I buy creatine monohydrate?
PolyBlueChem supplies creatine monohydrate (CAS 6020-87-7) in standard and micronised grades. Contact our team for specifications, COA and a quotation; see also our creatine monohydrate buying guide.