Recently, electrospun polymeric nanofibers have proven to be an interesting strategy for drug delivery systems application. The high surface-to-volume ratio of the fibers can improve some processes, such as cell binding and proliferation, drug loading, and mass transfer processes. One of the most important and studied areas of electrospinning is in the drug delivery field, for the controlled release of active substances ranging from antibiotics and anticancer agents to macromolecules such as proteins and DNA. The advantage of this method is that a wide variety of low solubility drugs can be loaded into the fibers to improve their bioavailability or to attain controlled release. This review presents an overview of the reported drugs loaded into polymeric nanofibers, to be used as drug delivery systems. For instance, it presents the reports on drugs with different bioactivities such as antiinflammatory, anti-microbial, anticancer, cardiovascular, anti-histamine, gastrointestinal, palliative and contraceptive drugs, etc. It also analyzes the electrospinning techniques used in each system, as well as the polymers used as matrices for the preparation of the nanofibers; unfolding the advantages of electrospun polymeric nanofibers over other drug delivery systems. This review intends to enlist and summarize the reported literature concerning this topic. In addition, it proposes future research in the field.

Nowadays, electrospinning has become one of the most versatile, easy, and cost-effective techniques to engineer advanced materials used for many applications, especially in the biomedical and environmental areas. Like the numerous patents around the world, the increasing number of papers witnesses the huge potential of this simple process, and many companies have been emerged during the last years to exploit its innumerable applications. This article presents a critically selected overview of polymers that can be used to produce nanofibers, along with the biomedical applications of the resulting electrospun scaffolds. We have focused on about seven natural and synthetic polymers, but many more can be found in the literature, either as their pristine state or as composites with ceramics, metals, and other polymers. The description of some strategies for nanofiber production, and the characterization used to evaluate their optimization, has been discussed. Finally, several polymers have been recognized as highlights for future work.

No abstract

No abstract

Reversible addition-fragmentation chain transfer (RAFT) polymerization is used to prepare temperature-and pH-sensitive statistical copolymers with lower critical solution temperature (LCST) close to 38 ° C at pH 7.4 based on N -isopropylacrylamide and methacrylic acid derivative comonomers with a p K a close to 6. Statistical copolymers are re-activated to prepare amphiphilic block copolymers and star polymers with cross-linked core. The LCST is maintained by varying the architecture; however, the LCST originated behaviour changes due to self-aggregation. Statistical copolymers and short block copolymers show complex aggregation, whereas midsize block copolymers and star polymers show shrinkage of aggregate dimensions. The pH of the medium has a profound impact on the self-assembling behaviour of the different polymer architectures.

Electrospinning is a very versatile techniqueused for many purposes, such as tissue engineering, textiles, air and water treatment filter, solar cells, and drug delivery systems, among others. This method is cheap, easy to handle, reproducible when ambient parameters are controlled, and can be used for many formulations. The objective of this review is to enlist and emphasize the advantages and disadvantages of different methods for incorporating therapeutic drugs in a drug delivery system with electrospinning. The importance of the research to create new and innovative drug carriers is high, because of their efficiency of transporting the bioactive agent to the target zone, avoiding secondary effects in the body. Nanofibers and nanoparticles have become an important strategy in pharmacology due to their physicochemical and biocompatible properties useful for this purpose. Among the techniques compared are blending coaxial, emulsion and surface modification electrospinning, followed by electrospray and coaxial electrospray. The present review concludes that every technique has advantages and disadvantages and, not all drugs can be loaded with any method, the strategy used will depend on the drug's physicochemical properties, target zone, polymeric characteristics, and required drug release rate. This chapter will serve as a starting point for when to choose one of the drug incorporation techniques mentioned.

No abstract

No abstract