FPGEE for National Association of Boards of Pharmacy (NABP) Practice Exam 2026 - Free NABP Practice Questions and Study Guide

Cellulose acetate is not typically utilized in the preparation of gels, which is why it is the correct choice in this context. Gels are often formed through the interaction of polymers with liquids, leading to a semi-solid structure that retains moisture and provides a suitable medium for various applications.

Bentonite is a clay mineral primarily composed of montmorillonite, which is widely used in gel formulations due to its ability to swell and create a viscous gel-like substance when mixed with water. Gelatin is a protein derived from collagen that is well-known for its gelling properties and is used in various pharmaceuticals and food products to create smooth, stable gels. Carbomers are a class of polymers used extensively in gel formulations for their ability to impart viscosity and stabilize emulsions, making them a popular choice in both cosmetic and pharmaceutical gels.

In contrast, cellulose acetate is primarily recognized as a thermoplastic polymer used in applications such as membranes and films, rather than for gel formation. Its characteristics do not lend themselves to swell or form a gel in the same way that the other polymers do, which is why it stands out as the option that is not used in gel preparation.