**7.1 Types of polymers used as drug carriers**

Not all polymers can be used for drug carriers, these polymers have to possess specific characteristics such as biocompatibility, biodegradability, permit drug loading, permit mass transfer, and respond to certain stimuli, among other characteristics [70]. Some examples of these polymers and their properties can be listed in **Table 1**:


*PCL: Poly (caprolactone); PVA: Poly (vinyl alcohol); PVP: Poly (vinyl pyrrolidone); PNIPAM: Poly (N-isopropyl acrylamide); PAA: Poly (acrylic acid).*

## **Table 1.**

*Most of the reported polymers are used for drug carriers' fabrication in drug delivery systems.*

Depending on their polymeric functional groups, antibiotics, anticancer agents, and biomolecules such as nucleic acids and proteins can be loaded [1], where surface morphology and structure of the polymeric nanofibers are key features for regulating the delivery rate and quantity of the drug. Also, the surface of the polymers can protect the bioactive loaded molecules from corrosion or degradation of the enzyme, water, or gastric acid, prolonging the effectivity of the pharmaceutical drug [43].
