Fabrication and evaluation of cationic exchange nanofibers for controlled drug delivery systems

Electrospinning technologies for the delivery of Biopharmaceuticals: Current status and future trends

This review provides an in-depth exploration of electrospinning techniques employed to produce micro- or nanofibres of biopharmaceuticals using polymeric solutions or melts with high-voltage electricity. Distinct from prior reviews, the current work narrows its focus on the recent developments and advanced applications in biopharmaceutical formulations. It begins with an overview of electrospinning principles, covering both solution and melt modes. Various methods for incorporating biopharmaceuticals into electrospun fibres, such as surface adsorption, blending, emulsion, co-axial, and high-throughput electrospinning, are elaborated. The review also surveys a wide array of biopharmaceuticals formulated through electrospinning, thereby identifying both opportunities and challenges in this emerging field. Moreover, it outlines the analytical techniques for characterizing electrospun fibres and discusses the legal and regulatory requirements for their production. This work aims to offer valuable insights into the evolving realm of electrospun biopharmaceutical delivery systems.

Novel long-acting brimonidine tartrate loaded-PCL/PVP nanofibers for versatile biomedical applications: fabrication, characterization and antimicrobial evaluation

The global state of antibiotic resistance highlights the necessity for new drugs that can treat a wide range of microbial infections. Drug repurposing has several advantages, including lower costs and improved safety compared to developing a new compound. The aim of the current study is to evaluate the repurposed antimicrobial activity of Brimonidine tartrate (BT), a well-known antiglaucoma drug, and to potentiate its antimicrobial effect by using electrospun nanofibrous scaffolds. BT-loaded nanofibers were fabricated in different drug concentrations (1.5, 3, 6, and 9%) via the electrospinning technique using two biopolymers (PCL and PVP). Then, the prepared nanofibers were characterized by SEM, XRD, FTIR, swelling ratio, and in vitro drug release. Afterward, the antimicrobial activities of the prepared nanofibers were investigated in vitro using different methods against several human pathogens and compared to the free BT. The results showed that all nanofibers were prepared successfully with a smooth surface. The diameters of nanofibers were reduced after loading of BT compared to the unloaded ones. In addition, scaffolds showed controlled-drug release profiles that were maintained for more than 7 days. The in vitro antimicrobial assessments revealed good activities for all scaffolds against most of the investigated human pathogens, particularly the one prepared with 9% BT which showed superiority in the antimicrobial effect over other scaffolds. To conclude, our findings proved the capability of nanofibers in loading BT and improving its repurposed antimicrobial efficacy. Therefore, it could be a promising carrier for BT to be used in combating numerous human pathogens.

Novel Slippery Liquid-Infused Porous Surfaces (SLIPS) Based on Electrospun Polydimethylsiloxane/Polystyrene Fibrous Structures Infused with Natural Blackseed Oil

Hydrophobic fibrous slippery liquid-infused porous surfaces (SLIPS) were fabricated by electrospinning polydimethylsiloxane (PDMS) and polystyrene (PS) as a carrier polymer on plasma-treated polyethylene (PE) and polyurethane (PU) substrates. Subsequent infusion of blackseed oil (BSO) into the porous structures was applied for the preparation of the SLIPS. SLIPS with infused lubricants can act as a repellency layer and play an important role in the prevention of biofilm formation. The effect of polymer solutions used in the electrospinning process was investigated to obtain well-defined hydrophobic fibrous structures. The surface properties were analyzed through various optical, macroscopic and spectroscopic techniques. A comprehensive investigation of the surface chemistry, surface morphology/topography, and mechanical properties was carried out on selected samples at optimized conditions. The electrospun fibers prepared using a mixture of PDMS/PS in the ratio of 1:1:10 (g/g/mL) using tetrahydrofuran (THF) solvent showed the best results in terms of fiber uniformity. The subsequent infusion of BSO into the fabricated PDMS/PS fiber mats exhibited slippery behavior regarding water droplets. Moreover, prepared SLIPS exhibited antibacterial activity against Staphylococcus aureus and Escherichia coli bacterium strains.

Modification of Polylactide Nonwovens with Carbon Nanotubes and Ladder Poly(silsesquioxane)

Electrospun nonwovens of poly(L-lactide) (PLLA) modified with multiwall carbon nanotubes (MWCNT) and linear ladder-like poly(silsesquioxane) with methoxycarbonyl side groups (LPSQ-COOMe) were obtained. MWCNT and LPSQ-COOMe were added to the polymer solution before the electrospinning. In addition, nonwovens of PLLA grafted to modified MWCNT were electrospun. All modified nonwovens exhibited higher tensile strength than the neat PLA nonwoven. The addition of 10 wt.% of LPSQ-COOMe and 0.1 wt.% of MWCNT to PLLA increased the tensile strength of the nonwovens 2.4 times, improving also the elongation at the maximum stress.

Needleless electrospinning system with wire spinneret: an alternative way to control morphology, size, and productivity of nanofibers

Electrospinning is a versatile method to produce nanofibers. Electrospun nanofibers have been extensively used in many industrial applications such as wound dressing, sensor, protective clothing, and filters. However, producing nanofibers efficiently through a single-needle electrospinning technique is still challenging. In this study, a system of needleless electrospinning with a wire spinneret was utilized to produce Polyvinylpyrrolidone (PVP) nanofibers. Process parameters comprised concentration of solution, applied voltage, flow rate of solution, collection distance, and diameter of the wire spinneret were altered to examine morphology, diameter, and productivity of the produced fibers. SEM images showed that morphology of the produced fibers was affected by concentration of PVP solution. Moreover, diameter of the produced fibers could be varied by controlling the process parameters. Our needleless electrospinning system has proved to be more productive in producing fibers than the single-needle electrospinning system.

Human mouthfeel panel investigating the acceptability of electrospun and solvent cast orodispersible films

A human panel study was performed to investigate the acceptability of orodispersible electrospun and solvent cast films. 50 healthy volunteers took two drug-free samples of polyvinyl alcohol films prepared by the two methods. On a 5-point hedonic scale, the volunteers assessed the films' perceived size, stickiness, thickness, disintegration time, thickening effect on saliva, and handling. The films manufactured by both methods were similar in their end-user acceptability. The modal values of perceived size, thickness, disintegration time, saliva thickening effect, and handling were high (4 or 5). However, for both, the stickiness mode was 2 (strongly sticky) and the only negative attribute. Both films were reported to take approximately 30 s to disintegrate completely in the mouth. Electrospun films scored similarly high to solvent cast orodispersible films in most attributes of end-user acceptability. Electrospun films were marginally preferred, with 27 out of 50 participants picking electrospinning when presented with a forced choice test of both fabrication methods. This is the first study to show that electrospinning enables the fabrication of orodispersible films that are acceptable to adult human participants in terms of handling and mouthfeel and suggests that the potential for clinical translation of such formulations is high.

Nanofibers containing tetracycline/β-cyclodextrin: Physico-chemical characterization and antimicrobial evaluation

This study aimed to compare two nanofiber drug delivery systems that were prepared with an electrospun process and have the potential to serve as adjuvants for the treatment of periodontal disease. The first system was composed of polycaprolactone loaded with tetracycline (TCN) and the second was composed of polycaprolactone loaded with tetracycline/β-cyclodextrin (TCN:BCD). An antimicrobial diffusion test was performed for each of these sets of nanofibers with the microorganisms, Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis, both of which contribute to periodontal disease. In vitro release profiles were also obtained, and the nanofibers were characterized by thermal analysis, x-ray powder diffraction, infrared absorption spectroscopy, and scanning electron microscopy. Profiles of the TCN and TCN:BCD nanofibers showed that drug release occurred for up to 14days. However, the TCN:BCD nanofibers appeared to better protect and enhance the biological absorption of TCN due to the formation of a TCN:BCD inclusion complex.

Engineering of biomimetic nanofibrous matrices for drug delivery and tissue engineering

Biomimetic nanofibers have emerged as promising candidates for drug delivery and tissue engineering applications. In this paper, recent advances on the fabrication and application of biomimetic nanofibers as drug carriers and scaffolding materials are reviewed. First, we delineate the three popular nanofiber fabrication techniques including electrospinning, phase separation and molecular self-assembly, covering the principal materials used for different techniques and surface functionalization strategies for nanofibers. Furthermore, we focus our interest on the nanofiber-based delivery strategies and underlying kinetics for growth factors and other bioactive molecules, following which we summarize the recent advances in the development of these nanofibrous matrices for bone, vascular and neural tissue engineering applications. Finally, research challenges and future trends in the related areas are discussed.