What Is Hydroxypropyl Methyl Cellulose?
Hydroxypropyl methyl cellulose, also known as its abbreviation HPMC. It is made from cellulose and is used as a thickening agent in foods. It comes in two types: HPC and L-HPC, the latter of which is a low-substituted form of HPC that acts as a binder and disintegrant in the medical world.
Cellulose can be divided into two grades, HPC (conventional) and L-HPC (short for low-substituted hydroxypropyl cellulose), based on the degree of substitution or amount of hydroxyl propoxy in the skeleton.
Because HPC has a larger amount of hydroxypropoxy than L-HPC, HPC is soluble in water, while L-HPC is insoluble in water. Because of this property, HPC can be used in aqueous solutions, while L-HPC cannot.
Cellulose is a glucose polymer containing hydroxyl groups (-OH) that can be replaced by hydroxyl propoxy groups (-OCH 2 ChohCH 3) to produce HPC. The mechanism is the same as that of sodium CMC.
Since the hydroxyl added to the hydroxyl propoxy group can also be etherified, the manufacturing process can be further facilitated.
HPC can be used in foods as thickeners, emulsifiers and stabilizers in foods and cosmetics. L-HPC is commonly used as a disintegrating agent and binder for tablets in pharmaceutical applications.
Food and beverage
HPC keeps burgers, pizzas, chicken and other foods fresh by spraying them on the surface before cooking them. During cooking, it can disintegrate quickly in less than 3 minutes.
HPC acts as a stabilizer in ice cream and frozen milk to prolong storage time and improve overflow; It is used as a coating on chocolate to prevent softening, oxidation and mildew of chocolate when stored at freezing temperatures.
It is also used to stabilize bulk foods. It has excellent foaming properties and works well with vegetable oils.
According to the "European Commission Database of Information on Substances and Ingredients in Cosmetics", HPC can be used as adhesives, emulsifiers, emulsion stabilizers, film forming agents and viscosity control agents in cosmetics and personal care products.
L-HPC can be used as a disintegrating agent because of its swelling in water. Also, due to its good compressibility and binding ability, it is beneficial for both wet and dry mixing in hard tablets.
Let's look at the details.
L-HPC absorbs water and significantly expands its volume, although it is not suitable for use in water. This swelling ability accelerates disintegration and increases the fineness of the tablet dispersion.
In both vitamin C tablets and aspirin tablets, L-HPC showed better disintegrating ability than other disintegrating agents (e.g., starch sodium glycoacetate).
L-HPC can be used as a binder for direct compression and wet granulation tablets. L-HPC increases the hardness of the tablet compared to other excipients, such as sodium carboxymethyl cellulose crosslinked.
And because it is non-ionic, it improves the bioavailability of the API. At the same moisture content, it is almost impossible to react with the active ingredient in the tablet as compared to ionic excipients.
Treat dry eyes
Hydroxypropyl fiber is an ingredient in many prescriptions for treating dry eye and other eye diseases, such as keratitis, that reduce corneal sensitivity.
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