Hydroxyethyl cellulose is a gelling and thickening agent derived from cellulose

Cellulose

Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to over ten thousand β linked D-glucose units....

. It is widely used in cosmetics, cleaning solutions, and other household products.
Hydroxyethyl cellulose and methyl cellulose are frequently used with hydrophobic drugs in capsule formulations, to improve the drugs' dissolution in the gastrointestinal fluids. This process is known as "Hydrophilization

Hydrophilization

Hydrophilization is a process used for hydrophobic drugs to increase their release rate from capsules, which is dependent on the rate of dissolution, by covering the surface of the drug particles with minute droplets of a hydrophilic polymer solution....

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