Search

Porous nanofiber electrospun of polyvinylidene fluoride (PVDF)/pectin was successfully developed using electrospinning method containing benzalkonium chloride (BAC) as a drug model for the controlled drug delivery system assessment. The electrospun was tested for its mechanical, morphological, and wettability properties. Scanning electron microscope (SEM) micrograph demonstrated that the smooth surfaces of nanofibers morphology had achieved up to 2 wt% pectin inclusion with optimum fiber diameter, 143 ± 1.4 nm. The optimized scaffold PVDF/Pectin showed that the reduction of mechanical integrity and optimum value of tensile strength, modulus strength, and elongation at break were 5.98 ± 0.17 MPa, 16.82 ± 0.10 MPa, and 79.3 ± 1.3% MPa. Water contact angle analysis and degree of swelling suggested that inclusion of pectin had enhanced the wettability properties of hydrophobic PVDF electrospun with highest swelling capacity achieved of 78.9 ± 1.7%. The in vitro drug release tests using BAC, which was released from the hybrid electrospun nanofibers, achieved prolonged release profile due to elimination of the uncontrollable initial burst release. Kinetic release study from Higuchi Model and Korsmeyer-Peppas further validates that the drug release mechanism is only influenced by the diffusion factor. The present study indicates the potential of PVDF/pectin electrospun nanofibers to be exploited as a tool for sustainable drug delivery system. [ABSTRACT FROM AUTHOR]

The application of nanofibrous scaffold in tissue engineering has great potential in solving the drawbacks of conventional tissue/organ transplant procedures. This present work aims to evaluate the effect of polyvinyl alcohol (PVA) inclusion on the physical properties of polyvinylidene fluoride (PVDF) nanofibrous membrane fabricated via the electrospinning method and its potential as an artificial tissue scaffold. The physical performance of electrospun PVDF/PVA samples was assessed by field emission scanning electron microscope (FESEM), tensile strength, water contact angle (WCA), degree of swelling, conductivity level, and Fourier transform infrared (FTIR) spectroscopy. Based on the physical characterisations, sample 90PVDF/10PVA with the PVDF-to-PVA ratio of 90:10 was the optimum composition, where the electrospun samples exhibit the most balanced properties that meet the requirement for artificial soft tissue replacement. In vitro studies using human dermal fibroblast (HDF) cells show that the PVDF/PVA nanofibrous scaffold successfully enhanced the adhesion and proliferation of cells compared to the neat PVDF scaffold as indicated by the MTT assay and Live/Dead kit. Overall results show the potential of PVDF/PVA nanofibrous membrane as a promising material suitable for soft tissue engineering applications. [ABSTRACT FROM AUTHOR]

This work reports the surface modification of 3D printed PLA scaffold with chitosan and its hydroxyapatite (HA) forming capability. PLA scaffold was fabricated using a desktop 3D printer followed by the inclusion of chitosan on the surface via surface entrapment. Confocal laser scanning microscopy (CLSM) images showed existence of chitosan entrapment with depth of 24 μm. Immersion of the modified PLA scaffold in simulated body fluid resulted in formation of apatite layers on the surface. Plus the entrapment method does not induce any cytotoxic response towards human fibroblast cell. This method provides a facile approach of obtaining 3D printed scaffold with good bioactivity thus has potential in biomimetic and tissue engineering. [ABSTRACT FROM AUTHOR]

This work reports the reinforcement of poly(vinyl alcohol) (PVA) hydrogel with halloysite nanotubes (HNT) as potential biomedical materials. The nanocomposite hydrogel was prepared using the facile and harmless process of freeze–thawing. Mechanical properties of the hydrogels were optimum at 2 wt% of HNT loading. Morphological and topographic analysis of the PVA/HNT hydrogel revealed excellent filler dispersion and smoothing of surface due to good compatibility between the components. Immersion of the PVA/HNT hydrogel in simulated body fluid for 7 days resulted in the formation of fully covered apatite layers on the surface. This is a good indication of bioactivity for artificial cartilage material. [ABSTRACT FROM AUTHOR]

Biomimetic hydroxyapatite (HA) growth on mercerized kenaf fiber (KF) was achieved by immersion in a simulated body fluid (SBF) solution with the addition of a chelating agent. An electron micrograph revealed uniform HA layers on the KF within 14 days of immersion with significant vibrational peaks of HA components. The tensile tests showed no significant drops in the unit break of the modified fibers. This new bone-like apatite coating on KF can be useful in the field of bone tissue engineering. The key motivation for this new approach was that it utilizes the abundantly available kenaf plant resource as the biobased template. [ABSTRACT FROM AUTHOR]

Transdermal drug delivery systems (TDDS) have drawn more interest from pharmaceutical scientists because they could provide steady blood levels and prevent the first-pass metabolism over a longer period. Polyvinyl alcohol (PVA) has been widely used in this application due to its biocompatibility, non-toxicity, nanofiber and hydrogel-forming ability. Despite those benefits, their morphology would easily be destroyed by continuous water absorption and contribute to burst drug release due to its hydrophilicity. The aim of this study was to prepare the diclofenac sodium (DS)-medicated dual layer PVA patch using a combination of electrospinning and cryogelation (freeze–thaw) methods to improve the physicochemical properties and drug compatibility and investigate the release of the DS-medicated dual layer PVA patch. Morphological observations using scanning electron microscopy (SEM) verified the polymer−polymer interaction between both layers, whereas Fourier transform infrared (FTIR) spectroscopy has demonstrated the compatibility of DS in PVA matrix up to 2% w/v of PVA volume. The DS loads were found amorphously distributed efficaciously in PVA matrix as no visible spectra of DS–PVA interaction were detected. The DS-medicated dual layer PVA patch with a thicker nanofiber layer (3-milliliter running volume), three freeze–thaw cycles and 2% DS loading labeled as 2%DLB3C show the lowest swelling capacity (18.47%). The in vitro assessment using Franz diffusion cells showed that the 2%DLB3C indicates a better sustained release of DS, with 53.26% of the DS being released after 12 h. The 2%DLB3C owned a flux (Jss) of 0.256 mg/cm2/h and a permeability coefficient (Kp) value of 0.020 cm/h. Thus, the results demonstrate that DS-medicated dual layer PVA patches prepared via a combination of electrospinning and cryogelation are capable of releasing drugs for up to 24 h and can serve as a drug reservoir in the skin, thereby extending the pharmacologic effects of DS. [ABSTRACT FROM AUTHOR]

The aim of this study is to prepare a dual layer polyvinyl (PVA) patch using a combination of electrospinning techniques and cryogelation (freeze-thaw process) then subsequently to investigate the effect of freeze-thaw cycles, nanofiber thickness, and diclofenac sodium (DS) loading on the physicochemical and mechanical properties and formulation of dual layer PVA patches composed of electrospun PVA nanofibers and PVA cryogel. After the successful preparation of the dual layer PVA patch, the prepared patch was subjected to investigation to assess the effect of freeze-thaw cycles, nanofiber thickness and percentages of DS loading on the morphology, physiochemical and mechanical properties. Various spectroscopic techniques such as scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), water contact angle, and tensile tests were used to evaluate the physicochemical and mechanical properties of prepared dual layer PVA patches. The morphological structures of the dual layer PVA patch demonstrated the effectiveness of both techniques. The effect of freeze-thaw cycles, nanofiber thickness, and DS percentage loading on the crystallinity of a dual layer PVA patch was investigated using XRD analysis. The presence of a distinct DS peak in the FTIR spectrum indicates the compatibility of DS in a dual layer PVA patch through in-situ loading. All prepared patches were considered highly hydrophilic because the data obtained was less than 90°. The increasing saturation of DS within the PVA matrix increases the tensile strength of prepared patches, however decreased its elasticity. Evidently, the increasing of electrospun PVA nanofibers thickness, freeze-thaw cycles, and the DS saturation has improved the physicochemical and mechanical properties of the DS medicated dual layer PVA patches, making them a promising biomaterial for transdermal drug delivery applications. [ABSTRACT FROM AUTHOR]