What Is Sodium Carboxymethylcellulose and Where Is It Used?

When you hear the name sodium carboxymethylcellulose, it may sound like something complicated. However, sodium carboxymethylcellulose is used in many things, from eye drops to ice cream and toothpaste. People also call it CMC, carmellose, or cellulose gum.

In this article, we will look at what it is, how it is made, where it is used, and what precautions should be taken when using it, all in simple language. Here, you will find everything you need to know to understand it.

What Is Sodium Carboxymethylcellulose?

It is essentially a modified form of cellulose. Cellulose is the substance found in plant cell walls. One major limitation of cellulose is that it does not dissolve in water. For this reason, it is difficult to use in applications where a water-soluble substance is needed.

When cellulose is modified, this problem is solved. This modified form is called sodium carboxymethylcellulose. You may also know it as CMC, carmellose, or cellulose gum. In food and beverages, its code is E466.

How Is It Made?

The process of making sodium carboxymethylcellulose involves two basic steps. First, cellulose is activated with sodium hydroxide. Then, this activated cellulose is reacted with chloroacetic acid.

After this reaction, carboxylic acid groups attach to the cellulose. These groups make cellulose capable of dissolving in water. In other words, the cellulose remains the same, but a change is made that allows it to dissolve in water.

Appearance and Properties

Sodium carboxymethylcellulose is a white or light cream-colored powder. It has no odor. When you mix it with water, it dissolves and forms a clear, sticky solution.

Its viscosity, or thickness, depends on three things: concentration, pH, and temperature. In other words, the amount of powder in the solution, the solution’s pH, and its temperature can all affect its thickness. It does not dissolve in most organic solvents.

Uses in Eye Drops

One of its most common uses is in eye drops. Here, sodium carboxymethylcellulose works like an artificial tear. It provides moisture to the eyes and relieves dry eyes.

These eye drops are commonly used by people whose eyes tend to become dry. They help maintain moisture on the surface of the eye.

Uses in Medicines

In the world of medicine, sodium carboxymethylcellulose serves several purposes. In tablets, it is used as a binder and disintegrant. A binder holds the ingredients of a tablet together, while a disintegrant helps the tablet break apart.

In suspensions, it acts as a stabilizer. It is also used as a bulk laxative. In other words, the same substance serves different purposes in medicines.

Uses in Food and Beverages

In food and beverages, sodium carboxymethylcellulose improves texture. It is used in ice cream, sauces, juices, and bakery items. In food, it is identified by the code E466.

When the texture of something is improved, it becomes more enjoyable to eat. This is why it is commonly used in many food products.

Cosmetics and Personal Care

In toothpaste, creams, lotions, and shampoo, it works as a thickener. A thickener means a substance that makes something thicker. This improves the consistency of these products and makes them easier to use.

Industrial Uses

Sodium carboxymethylcellulose has a wide range of industrial uses. It is used in detergents, paper, textiles, ceramics, paint, and oil drilling mud. It is also useful in industries that have no connection to food or medicine.

Batteries and Wound Care

It is used as a binder in the anodes of lithium-ion batteries. In addition, it is also used in wound care dressings. In other words, this substance is found in healthcare, food, household products, and technology.

Is It Safe?

Sodium carboxymethylcellulose is generally considered safe for use in food and medicine. The FDA and EFSA have approved it. This means that using it in normal amounts is generally considered acceptable.

However, as with any substance, there are some things to keep in mind when using it. These points are explained below in a simple way.

Side Effects and Warnings

Keep these points in mind when using sodium carboxymethylcellulose:

• Consuming very large amounts may cause bloating or diarrhea.
• Some people may rarely experience an allergic reaction.
• When used in eye drops, it may cause irritation, itching, and temporary blurred vision.
• You should consult a doctor during pregnancy or breastfeeding.
• It should not be used while wearing contact lenses.
• It is not suitable for children under 3 years old.

Pros and Cons

Pros:

• It dissolves in water and forms a clear, sticky solution.
• In eye drops, it provides moisture to the eyes and relieves dry eyes.
• It improves the texture of food.
• It is useful in medicines, cosmetics, industry, batteries, and wound care.
• It is generally considered safe for use in food and medicine.

Cons:

• Large amounts may cause bloating or diarrhea.
• Allergic reactions may rarely occur.
• Eye drops may cause irritation, itching, and temporary blurred vision.
• It is not suitable for use with contact lenses or for children under 3 years old.

What Does the Research Say?

Research on the effects of sodium carboxymethylcellulose on gut bacteria is still ongoing. There is no conclusive evidence about its effects in humans. Therefore, it is not yet possible to make a definite statement about this.

Conclusion

Sodium carboxymethylcellulose is a substance made by modifying cellulose, which allows it to dissolve in water. It is used in eye drops, medicines, food, cosmetics, industry, batteries, and wound care. It is generally considered safe, but precautions should be taken regarding large amounts, eye drop side effects, pregnancy, and young children. Research on gut bacteria is still ongoing, so a conclusive answer cannot yet be given.

FAQs

1. What does CMC mean?

CMC is the short name for sodium carboxymethylcellulose. It is also called carmellose and cellulose gum.

2. What is its code in food and beverages?

Its code in food and beverages is E466.

3. How is it made?

Cellulose is activated with sodium hydroxide and then reacted with chloroacetic acid. This attaches carboxylic acid groups, making it capable of dissolving in water.

4. Is it safe?

It is generally considered safe for use in food and medicine, and the FDA and EFSA have approved it.

5. What does it do in eye drops?

It works like an artificial tear, providing moisture to the eyes and relieving dry eyes.

6. Can it be used with contact lenses?

No, it should not be used while wearing contact lenses.

7. Is it suitable for young children?

It is not suitable for children under 3 years old.