Preparation of a composite hydrogel of polyvinyl alcohol/chitosan fiber with anisotropic properties for sustained drug release

Abstract

Hydrogel with anisotropic properties has promising potentials, while its fabrication is still challenging. In this work, chitosan fiber (CF) was designed to reinforce polyvinyl alcohol (PVA) hydrogel anisotropically. First, CF was pretreated in a weak acidic buffer to create rough surface as well as outwardstretched chitosan chain end segments, and then mixed with PVA in solution. A PVA/CFs composite hydrogel was thereafter prepared by casting the mixture with a pushing force followed by freeze-thawing cycles. The microstructure of the composite hydrogel was characterized by scanning electron microscopy, optical microscopy and Fourier transform infrared spectroscopy, and its mechanical properties at the directions parallel to and perpendicular to the casting force were measured. Our results indicate that the pre-treated CF can reinforce the PVA hydrogel effectively, especially along the casting force direction.

Effect of Specific Surface Area and Hydrophobicity of Electrospun Nanofibers on the Sustained Release Performance of Diclofenac Sodium

“…Biodegradable materials in the biomedical area are utilized as drug carriers to achieve magnetic, pH-responsive, temperature-responsive, and slow-release effects. − Common polymers used as drug carriers include polycaprolactone (PCL), − poly­(vinyl alcohol) (PVA), − polylactic acid (PLA), − sodium alginate, − chitosan, and others. − Ghosal and Nanda prepared sodium diclofenac layout-release hydrogels using hydrophilic hydroxypropyl methylcellulose modified to a hydrophobic form in combination with long-chain alkyl groups . Ghosal and Nanda prepared alginate films for modulation of DS release using a hydrogel approach. , Paul et al prepared halloysite nanotubes and its nanocomposite with chitosan for the delivery of diclofenac .…”

Designing Viscoelastic Gelatin-PEG Macroporous Hybrid Hydrogel with Anisotropic Morphology and Mechanical Properties for Tissue Engineering Application

“…On the other hand, PEG-a hydrophilic synthetic polymer with two hydroxyl end groups-is widely used in biomedical application because of its good biocompatibility, non-immunogenicity and resistance to protein adsorption [24]. Although structurally and mechanically anisotropic, hydrogel can be prepared by imparting a specific orientation of nanofillers, pores, fibrous networks and groove/ridge topographies which leverage magnetic or electric stimulation, electrospinning, 3D printing or unidirectional freeze-casting, [25][26][27][28][29][30][31][32][33][34]; however, the clinical translation of these hydrogels is impeded due to their strict, complex and cumbersome preparation processes, high cost, cytotoxicity, difficulty in terminal sterilization and lack of scalability [29]. Moreover, controlling the pore size and wall thickness of the anisotropic hydrogel is also important for tissue engineering application [28].…”