Novel SA@Ca2+/RCSPs core–shell structure nanofibers by electrospinning for wound dressings

AbstractA new type of medicated polymeric composite consisting of acyclovir (ACY), polyvinylpyrrolidone K60 (PVP) and polyethylene glycol 6000 (PEG) with core-shell structure were prepared by a coaxial electrospinning process. The composites could enhance the dissolution of the poorly water-soluble drug. The shell layers were formed from a spinnable working fluid containing the filament-forming PVP and citric acid while the core parts were prepared from an un-spinnable co-dissolving solution composed of ACY, sodium hydrate and PEG. Scanning electron microscope and transmission electron microscope observations demonstrated that the composites had a homogeneous linear topography with a slippery surface, a diameter of 670±130 nm, and an obvious core-shell structure. X-ray diffraction (XRD) and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy results demonstrated that the drug and citric acid contained in the core and shell parts were in an amorphous status. In vitro dissolution experiments exhibited that ACY was able to be free within 1 min, and the dissolution media were neutral due to acid-basic action within the core-shell structures. The medicated nanocomposites resulted from a combined usage of hydrophilic polymeric excipients PVP and PEG could provide a new solution to the problem associated with the dissolution of poorly water-soluble drugs.

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Effect of Solution Miscibility on the Morphology of Coaxial Electrospun Cellulose Acetate Nanofibers

Polymers ◽

10.3390/polym13244419 ◽

2021 ◽

Vol 13 (24) ◽

pp. 4419

Author(s):

Ke Yan ◽

Yao Le ◽

Hu Mengen ◽

Li Zhongbo ◽

Huang Zhulin

Keyword(s):

Cellulose Acetate ◽

Shell Structure ◽

Partial Solution ◽

Electrospinning Process ◽

Core Shell ◽

Electrospinning Technique ◽

Product Morphology ◽

The Core ◽

Core Shell Structure ◽

Structural Characterizations

Coaxial electrospinning (co-electrospinning) technique has greatly expanded the universality of fabricating core-shell polymer nanofibers. However, the effect of solution miscibility on the morphology of co-electrospun products remains unclear. Herein, different cellulose acetate (CA) solutions with high solution miscibility but distinctly different electrospinnability were used to survey the effect of solution miscibility on the co-electrospinning process. The structural characterizations show that co-electrospun products are composed of nanofibers with and without the core-shell structure. This indicates that partial solution mixing occurred during the co-electrospinning process instead of absolute no-mixing or complete mixing. Importantly, the solution miscibility also shows a significant influence on the product morphology. In particular, the transformation from nanofibers to microparticles was realized with the increase of core-to-shell flow ratio during the co-electrospinning of core electrosprayable CA/dimethylacetamide (DMAc) solution and shell electrospinnable CA/acetone-DMAc (2/1, v/v) solution. Results show that the solution miscibility exerts a significant effect on not only the formation of core-shell structure but also the product morphology. This work provides a new insight for the in-depth understanding of the co-electrospinning process.

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Long-Term Effect against Methicillin-Resistant Staphylococcus aureus of Emodin Released from Coaxial Electrospinning Nanofiber Membranes with a Biphasic Profile

Biomolecules ◽

10.3390/biom10030362 ◽

2020 ◽

Vol 10 (3) ◽

pp. 362 ◽

Cited By ~ 4

Author(s):

Peiwen Ye ◽

Suying Wei ◽

Chaohua Luo ◽

Qirui Wang ◽

Anzhang Li ◽

...

Keyword(s):

Electron Microscopy ◽

Staphylococcus Aureus ◽

Shell Structure ◽

Methicillin Resistant Staphylococcus Aureus ◽

Term Effect ◽

Coaxial Electrospinning ◽

Core Shell ◽

Long Term Effect ◽

Core Shell Structure

Methicillin-resistant Staphylococcus aureus (MRSA) is a serious and rapidly growing threat to human beings. Emodin has a potent activity against MRSA; however, its usage is limited due to high hydrophobicity and low oral bioavailability. Thus, the coaxial electrospinning nanofibers encapsulating emodin in the core of hydrophilic poly (vinylpyrrolidone), with a hygroscopic cellulose acetate sheath, have been fabricated to provide long-term effect against MRSA. Scanning electron microscopy and transmission electron microscopy confirmed the nanofibers had a linear morphology with nanometer in diameter, smooth surface, and core-shell structure. Attenuated total reflection-Fourier transform infrared spectra, X-ray diffraction patterns, and differential scanning calorimetric analyses verified emodin existed in amorphous form in the nanofibers. The nanofibers have 99.38 ± 1.00% entrapment efficiency of emodin and 167.8 ± 0.20% swelling ratio. Emodin released from nanofibers showed a biphasic drug release profile with an initial rapid release followed by a slower sustained release. CCK-8 assays confirmed the nontoxic nature of the emodin-loaded nanofibers to HaCaT cells. The anti-MRSA activity of the nanofibers can persist up to 9 days in AATCC147 and soft-agar overlay assays. These findings suggest that the emodin-loaded electrospun nanofibers with core-shell structure could be used as topical drug delivery system for wound infected by MRSA.

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A Method for Scale-Up of Grooved Nanofibers via Flat Off-Centered Core-Shell Structure Spinneret

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.989-994.556 ◽

2014 ◽

Vol 989-994 ◽

pp. 556-559 ◽

Cited By ~ 1

Author(s):

Hui Hui Wu ◽

Xiao Hua Meng ◽

Yong Chun Zeng

Keyword(s):

Production Rate ◽

Shell Structure ◽

Flat Surface ◽

Scale Up ◽

Electrospinning Process ◽

Core Shell ◽

Core Needle ◽

The Core ◽

Core Shell Structure ◽

Novel Design

An approach to the scale-up of grooved nanofibers via a flat off-centered core-shell structure spinneret has been developed in this study. The spinneret with a flat surface involves shell-holes and off-centered core-needles. The position of the core-needle in the hole and the electrospinning process do influence the formation and structure of the grooved nanofibers. The production rate of the core-shell nanofibers can be enhanced by increasing the hole and needle number of the spinneret. This novel design is expected to provide a promising method towards the massive production of grooved nanofibers.

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