Browsing by Author "Li, Jing-Song"
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Item Open Access Co-Printing of Vertical Axis Aligned Micron-Scaled Filaments Via Simultaneous Dual Needle Electrohydrodynamic Printing(Elsevier, 2018-05-08) Wang, Baolin; Wu, Shuting; Ahmad, Z.; Li, Jing-Song; Chang, Ming-WeiIn this study dual-needle electrohydrodynamic co-printing (DN-EHDCP) was developed to fabricate unique micron-scaled architectures based on multi-material fibrous (filamentous) morphologies. Two stainless steel needles (contributing towards dual needle design) were used to simultaneously co-print poly(ɛ-caprolactone) (PCL) and polyvinylpyrrolidone (PVP) polymers (using solvent based formulations including Fe 3 O 4 nano- particles and active pharmaceutical ingredient (API). Differences in polymer hydrophobicity and dissolution rate were used to modulate drug release (tetracycline hydrochloride, TE-HCL) from various co-printed configura- tions. Optical, scanning electron and fluorescent microscopy confirmed precision alignment and vertical stacking of both PVP and PCL printed fi laments. Process parameters were found to strongly influence co-print construct diameter. Fourier Transform Infrared (FTIR) spectroscopy confirmed spatial locations of both PVP and PCL filaments. TE-HCL release from co-printed formulations exhibited two phases; rapid and sustained. In vitro biological assay (using L929 cell lines) demonstrated construct biocompatibility. However, selective integration (spatial and quantity) of sacrificial PVP fibers (after rapid dissolution) provided a method of in situ void en- gineering for enhanced interfacial interaction for remaining PCL structures. The present study shows the de- velopment and use of simultaneously co-printed filaments in the vertical axis with potential to control drug release through alignment of individual filaments and material type. Furthermore, the use of composite matrix under an external stimulus is also demonstrated indicating multiple approaches to modulate API releaseItem Open Access Controlled Engineering of Highly Aligned Fibrous Dosage Form Matrices for Controlled Release(Elsevier, 2018-08-20) Wu, Shuting; Ahmad, Z.; Li, Jing-Song; Chang, Ming-WeiIn this study, complex drug-cellulose acetate (CA) composite films were designed and fabricated possessing pre-determined grid spacing for inter-connected fibrous films. Ibuprofen (IBU) was selected as the active ingredient. and grid spacing was varied between 300 to 500μm (fiber diameter~35μm) for various geometries. Process parameter impact on fiber morphology and deposition was investigated. FTIR confirmed IBU encapsulation and XRD analysis indicated the drug was dispersed (amorphous) in films. Inter-connected grid void geometry was shown to impact water contact behavior, and drug release mechanism was shown to be Fickian diffusion. Furthermore, drug release rate depended on geometry of engineered structures. The findings suggest a spatial design approach for modulated drug release from bespoke drug delivery dosage forms.Item Metadata only Controlled Morphing of Microbubbles to Beaded Nanofibers via Electrically Forced Thin Film Stretching(MDPI, 2017-07-03) Yao, Zhi-Cheng; Yuan, Qiantailang; Ahmad, Z.; Huang, Jie; Li, Jing-Song; Chang, Ming-WeiTopography and microstructure engineering are rapidly evolving areas of importance for biomedical and pharmaceutical remits. Here, PVA (Polyvinyl alcohol) microbubbles (diameter range ~126 to 414 μm) were used to fabricate beaded (beads-on) nanofibers using an electrohydrodynamic atomization (EHDA) technique. Mean fiber diameter, inter-bead distance, and aspect ratio (AR) were investigated by regulating EHDA process parameters. PVA fibers (diameter range ~233 to 737 nm) were obtained possessing bead ARs in the range of ~10 to 56%. AR was used to modulate hydrophilicity and active release.Item Open Access Designer fibers from 2D to 3D – Simultaneous and controlled engineering of morphology, shape and size(Elsevier, 2017-10-09) Yao, Zhi-Cheng; Zhang, Chunchen; Ahmad, Z.; Huang, Jie; Li, Jing-Song; Chang, Ming-WeiTopography and surface morphology of micrometer and nanometer scaled fibrous biomaterials are crucial for bioactive component encapsulation, release, promoting cell proliferation and interaction within biological environment. Specifically, for drug delivery and tissue repair applications, surface engineering provides control on both aspects in tandem. In this study, the bioactive component (ganoderma lucidum spore polysaccharide (GLSP)) was loaded into zein prolamine (ZP) fiber matrices via coaxial electrospinning (CES) technique. During the CES process, various outer layer enveloping fluids were used to modulate fiber topography in-situ (from 2D to 3D). SEM and water contact angle tests indicate enveloping media impact electrospun fiber diameter (ranging from 400 nm to 3.0 μm) and morphologies (from flat ribbon-like to solid cylindrical structures), with the latter impacting GLSP release profile. Furthermore, CCK-8 assay assessment indicates fibroblast cell proliferation (L929 cell line), while cell extension was also observed for modified ZP fibers. The results demonstrate potential applications of modified fiber morphologies, which are tailored in-situ without impacting chemical stability and encapsulation.Item Open Access Development of Random and Ordered Composite Fiber Hybrid Technologies for Controlled Release Functions(Elsevier, 2018-03-06) Wang, Baolin; Ahmad, Z.; Huang, J.; Li, Jing-Song; Chang, Ming-WeiFibrous technologies (such as membranes, films, patches and filters) and their enabling engineering platforms have gained considerable interest over the last decade. In this study, novel fibrous constructs from a unique engineering platform were developed based on hybrid electrohydrodynamic (EHD) technology; incorporating functional and bioactive materials within random and aligned fibrous formulation geometries. Complex constructs were engineered using 3D printing (polycaprolactone, PCL, for sustained delivery) and electrospinning (polyvinylpyrolidone, PVP, for rapid release) in an intercalating material layer-by-layer format using a side-by-side technological approach. Here, structure generation proceeded with deposition of ordered PCL fibers enabling well-defined void size and overall dimension, after which randomly spun PVP fibers formed a construct overcoat (as a membrane). Differences between polymer dissolution rate, hydrophilicity, mechanical properties and functional material hosting (and linked external auxiliary magnetic field trigger) provided opportunities to modulate antibiotic drug (tetracycline hydrochloride, TE-HCL) release. In vitro cell studies using human umbilical vein blood vessel cell line demonstrated device biocompatibility and Escherichia Coli (E. coli) was selected to demonstrate anti-bacterial function. Overall, a new hybrid engineering platform to prepare customizable and exciting multi-faceted drug release constructs is elucidated.Item Open Access Dual Rotation Centrifugal Electrospinning: A Novel Approach to Engineer Multi-Directional and Layered Fiber Composite Matrices(Springer, 2018-10-19) Wang, Li; Wang, Baolin; Ahmad, Z.; Li, Jing-Song; Chang, Ming-WeiIn this study, a dual rotation centrifugal electrospinning system (DRCES) is designed, developed and used to prepare medicated fabrics. Through simultaneous rotation of both spinneret and collector; multi-directional blended fiber matrices (PVP and TPU) were deposited directly on the rotating collector. To detail the process, key stages of the centrifugal electrospinning process are elaborated, and the influence of gas infusion and collector rotation speed on resulting fiber morphologies were explored. Multi-directional fibrous structures show in vitro biocompatibility (fibroblast). Regulation of drug release rate was achieved using polymer composition and filament alignment. This study demonstrates a rapid fabrication method (~ 50 g/h) to engineer layered fibrous structures using DRCES; which provides a foundation for preparing complex drug matrices (single and multi–directional) for tailored active component release.Item Open Access Elastic Anti-Bacterial Membranes Comprising Particulate Laden Fibers for Wound Healing Applications(Elsevier, 2018-10-04) Lia, Yudong; Zhang, Chunchen; Zhu, Li-Fang; Ahmad, Z.; Li, Jing-Song; Chang, Ming-WeiMedicated skin care products are available in various forms; ranging from lotions and creams to bandages and membranes. In this study, anti-bacterial particulate laden fibrous membranes were prepared via electrospraying of tetracycline hydrochloride (TE-HCL) loaded poly(ε-caprolactone) (PCL) particles alongside electrospinning of thermoplastic polyurethane (TPU) fibers, through which both mechanical and biological aspects of a complete membrane system can be achieved. Random (R) and ordered (P and V) patterns of TPU fibrous membranes (FMs) were afforded using a rotating collector. Water contact angle and bacterial inhibition zone tests were performed to assess suitability of the system specifically for wound care. Stress-strain and in-vitro drug release tests were performed to assess suitability of newly developed systems specifically for hybrid membranes (HMs). The highest tensile strength (32.1 ± 4.9 MPa) with elasticity (104.2 ± 6.0 %) and the most sustained release rate indicate HMs (P) are potentially suitable materials for wound care applications.Item Open Access Essential Oil Bioactive Fibrous Membranes Prepared via Coaxial Electrospinning(wiley, 2017-06-07) Yao, Zhi-Cheng; Chen, Si-Cong; Ahmad, Z.; Huang, Jie; Chang, Ming-Wei; Li, Jing-SongA novel antimicrobial composite material was prepared by encapsulating orange essential oil (OEO) in zein prolamine (ZP) via the coaxial electrospinning (ES) technique. By manipulating process parameters, the morphological features of ZP/OEO fibers were modulated. Fine fibers with diameters ranging from 0.7 to 2.3 μm were obtained by regulating ZP solution concentration and process parameters during the ES process. Optimal loading capacity (LC) and encapsulation efficiency (EE) of OEO in fibrous ZP mats were determined to be 22.28% and 53.68%, respectively, and were achieved using a 35 w/v% ZP ES solution. The encapsulation of OEO was found to be reliant on ZP solution concentration (the enveloping medium). SEM analysis indicates the surface morphology of ZP/OEO electrospun fibers is dependent on ZP solution loading volume, with lower ZP concentrations yielding defective fibrous structures (for example, beaded and spindled-string like morphologies). Furthermore, this loading volume also influences OEO LC, EE, mat water contact angle and oil retention. CCK-8 assay and cell morphology assessment (HEK293T cells) indicate no significant change with electrospun ZP and ZP/OEO fibrous membranes over an 8 h period. Antimicrobial activity assessment using Escherichia coli, suggests composite nonwovens possess sterilization properties; elucidating potential application in active food packaging, food preservation and therefore sustainability.Item Open Access Fabrication of Stacked-Ring Netted Tubular Constructs Via 3D-Template Electrohydrodynamic Printing(Springer, 2018-05-24) Wang, Li; Luo, Y.; Ahmad, Z.; Li, Jing-Song; Chang, Ming-WeiElectrohydrodynamic (EHD) printing is an emerging additive manufacturing process which provides several opportunities for advanced fiber patterning and alignment. In this study, stacked-ring netted tubular constructs were printed using controlled EHD fiber deposition. To achieve this, a modified EHD system was developed which integrated air and heating moduli, in addition to a 3D cylindrical collector. The impact of additional peripheral components was evident through enhanced solidification of as-formed polycaprolactone (PCL) polymer fiber prints, which further enabled fabrication of stacked PCL fiber rings. Subsequently, stacked-ring netted tubular constructs (via x-axis deposition manipulation) were fabricated. Electric-field simulations were used to elucidate construct formation mechanism. The modified printing system provides much needed control on fiber deposition and solidification; enabling integration of essential bio-interface features and morphologies (e.g. tissue structure and surface mimicry) for advanced 3D biomaterial engineering.Item Open Access Ganoderma lucidum polysaccharide loaded sodium alginate micro-particles prepared via electrospraying in controlled deposition environments(Elsevier, 2017-03-28) Yao, Zhi-Cheng; Jin, Li-Jie; Ahmad, Z.; Huang, Jie; Chang, Ming-Wei; Li, Jing-SongGanoderma lucidum polysaccharide (GLP) is a functional food source deployed in preventative medicine. However, applications utilizing GLP are limited due to oxidative and acidic environmental damage. Advances in preserving GLP structure (and therefore function), in situ, will diversify their applications within biomedical fields (drug and antibacterial active delivery via the enteral route). In this study, GLP loaded sodium alginate (NaAlg) micro-particles (size range 225–355 μm) were generated using the electrospray (ES) process. The loading capacity and encapsulation efficiency of GLP for composite particles (collected at different temperatures) were ∼23% and 71%, respectively. The collection substrate (CaCl2, 1–20 w/v%) concentration was explored and preliminary findings indicated a 10 w/v% solution to be optimal. The process was further modified by manipulating the collection environment temperature (∼25 to 50 °C). Based on this, NaAlg/GLP micro-particles were engineered with variable surface morphologies (porous and crinkled), without effecting the chemical composition of either material (GLP and NaAlg). In-vitro release studies demonstrated pH responsive release rates. Modest release of GLP from micro-particles in simulated gastric fluid (pH ∼1.7) was observed, while rapid release was exhibited under simulated intestinal conditions (pH ∼7.4). Release of GLP from NaAlg beads was the greatest from samples prepared at elevated environmental temperatures. These findings demonstrate a facile route to fabricate GLP-NaAlg loaded micro-particles with various shapes, surface topographies and release characteristics via a one-step ES process.Item Open Access High Throughput Engineering and Use of Multi-Fiber Composite Matrices for Controlled Active Release(Elsevier, 2018-08-18) Wang, Li; Zhang, Chunchen; Wang, Hui-Min David; Ahmad, Z.; Li, Jing-Song; Chang, Ming-WeiA tri-compartment centrifugal electrospinning system (TCCES) was designed and used to fabricate multiple fiber membranes (from individual polyvinyl pyrrolidone (PVP), thermoplastic polyurethane (TPU) and poly-methyl methacrylate (PMMA) fibers). Controlled engineering of membrane composition presents opportunities to control mechanical and water contact angle characteristics. Furthermore, control on drug release rate is achieved based on active hosting fiber type contributing towards the overall membrane. The current system enables a high degree of alignment, production rate and variations to composition, indicating clear potential in biomedical fields requiring the use of encapsulated or embedded drug in membrane materials.Item Open Access Mass and controlled fabrication of aligned PVP fibers for matrix type antibiotic drug delivery systems(Elsevier, 2016-08-31) Wang, Li; Chang, M-W.; Ahmad, Z.; Zheng, Hongxia; Li, Jing-SongItem Open Access Non-concentric multi-compartment fibers fabricated using a modified nozzle in single-step electrospinning(Elsevier, 2017-05-08) Wang, Baolin; Wang, Meidi; Chang, Ming-Wei; Ahmad, Z.; Huang, Jie; Li, Jing-SongMulti-compartment fibers with well-defined regions and functional media hosting potential provide co-encapsulation opportunities for a variety of bio-molecules, drugs and even nutrients. In this research, fibers possessing multiple compartments were prepared using the single-step electrospinning method and a modified non-concentric multi-needle. Polyvinyl pyrrolidone (PVP) was used as the fiber shell material, while ketoconazole (KCZ, model drug) and Sudan Red (model probe) were encapsulated as two separate segments running along the fiber length. Multi-compartment fiber morphology and structure were examined using optical and electron microscopy. The effect of flow rate on fiber morphology was also investigated and the release of encapsulated KCZ and Sudan Red was examined using UV spectroscopy. The results present an efficient and promising method to engineer multi-compartment fibers in a single step for several biomedical applications in lieu.Item Open Access Pharmacological Effects of Natural Ganoderma and Its Extracts on Neurological Diseases: A Comprehensive Review(Elsevier, 2018-10-18) Zhao, C.; Zhang, Chunchen; Xing, Z.; Ahmad, Z.; Li, Jing-Song; Chang, Ming-WeiGanoderma, has been used for clinical applications for thousands of years as a highly-nutritious and significantly-effective medicinal herb. The active components and efficacy of Ganoderma are constantly being explored and supplemented every year. In recent years, more and more literature has reported the pharmacological effects of Ganoderma on anti-tumor, liver protection and immunity enhancement, especially on neuroprotection. Numerous research works on the neuroprotective effects of Ganoderma have been documented (e.g., modulation of neurogenesis, amelioration of Alzheimer's disease, therapeutic effect on epilepsy, the protective effect on neural cells in stroke injury, etc.) thus it has drawn increasing attention. However, an integrated and comprehensive review of recent research findings has not been detailed in any great depth. Therefore, the purpose of this review is to summarize and elucidate recent progress of neuroprotective effects of natural Ganoderma and its extracts.Item Metadata only Preparation of active 3D film patches via aligned fiber electrohydrodynamic (EHD) printing(Nature, 2017-03-08) Wang, Jun-Chuan; Zheng, Hongxia; Chang, Ming-Wei; Ahmad, Z.; Li, Jing-SongItem Open Access Surface modified electrospun porous magnetic hollow fibers using secondary downstream collection solvent contouring(Elsevier, 2017-06-19) Wu, Shuting; Wang, Baolin; Ahmad, Z.; Huang, Jie; Chang, Ming-Wei; Li, Jing-SongIn this study, a relatively facile porous magnetic hollow fiber engineering electrospinning method is demonstrated, which modulates fiber morphology based on secondary solvents (at variable temperatures). To demonstrate this, polycaprolactone (PCL) polymer and iron oxide nanoparticles (NPs) were used as the fibrous composite matrix. Fiber pore size increased with increasing immersed secondary solvent temperature. By contouring the surface morphology (via modulation of secondary collection solvents) of hollow magnetic fibers, drug (ketoconazole) release kinetics from spun mats were tuned. Furthermore, applying an external AC magnetic field to NP embedded porous fibers enhanced drug release. These findings are promising for alternative engineering, tuning and controlling fiber morphology and drug release behavior.Item Open Access Synthesis and Evaluation of Herbal Chitosan from Ganoderma Lucidum Spore Powder for Biomedical Applications(Springer, 2018) Zhu, Li-Fang; Yao, Zhi-Cheng; Ahmad, Z.; Li, Jing-Song; Chang, Ming-WeiChitosan is an extremely valuable biopolymer and is usually obtained as a byproduct from the shells of crustaceans. In the current work, chitosan is obtained from an herbal source (Ganoderma lucidum spore powder (GLSP)) for the first time. To show this, both standard (thermochemical deacetylation, (TCD)) and emerging (ultrasound-assisted deacetylation (USAD)) methods of chitosan preparation were used. The obtained chitosan was characterized by elemental analysis, XRD (X-ray diffraction), FT-IR (Fourier transform infrared spectroscopy) and thermogravimetric measurements. The process resulted in chitosan possessing comparable values of DD, [η] and ¯Mv to the commercial product. Chitosan obtained via both processes (TCD and USAD) displayed excellent biocompatibility; although the USAD prepared biopolymer exhibited significantly improved fibroblast (L929 cell) viability and enhanced antibacterial zones for both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The findings of new herbal chitosan mark key developments of natural biomaterials; marking a potential shift from conventional sea-based organisms.Item Open Access Targeting Oxidative Stress Using Tri-Needle Electrospray Engineered Ganoderma Lucidum Polysaccharide-loaded Porous Yolk-Shell Particles(Elsevier, 2018-09-21) Xing, Z.; Zhang, C; Zhaoc, C.; Ahmad, Z.; Li, Jing-Song; Changa, M.Chronic lung diseases (e.g. chronic obstructive pulmonary disease and asthma) are associated with oxidative stress and common treatments include various types of inhalation therapies. In this work ganoderma lucidum polysaccharide (GLP), a naturally occurring antioxidant is loaded into porous Poly (ε-caprolactone) (PCL) particles using a single step tri-needle coaxial electrospray process (Tri-needle CES); with a view to develop therapies to combat oxidative stress. Based on the core-shell structure of porous yolk shell particles (YSPs), GLP-loaded YSPs displayed a bi-phasic release pattern. In vitro cell studies indicate GLP-loaded porous YSPs display good biocompatibility and positive attributes towards H2O2-induced oxidative stress in MRC-5 cells and dramatically attenuate intracellular reactive oxygen species (ROS) levels as well as significantly increase cell viability. In vivo inhalation studies indicate that GLP-loaded porous YSPs can be delivered to deep lung tissue and remain deposited for over 48 h and are subsequently removed by natural clearance mechanisms. Based on current findings GLP-loaded porous YSPs are suitable for pulmonary delivery and display good inhalation therapy potential to treat chronic lung diseases.Item Open Access Tri-Needle Coaxial Electrospray Engineering of Magnetic Polymer Yolk–Shell Particles Possessing Dual-Imaging Modality, Multiagent Compartments, and Trigger Release Potential(ACS Publications, 2017-06-07) Zhang, Chunchen; Yao, Zhi-Cheng; Ding, Qiuping; Choi, James J.; Ahmad, Z.; Chang, Ming-Wei; Li, Jing-SongParticulate platforms capable of delivering multiple actives as well as providing diagnostic features have gained considerable interest over the last few years. In this study, magnetic polymer yolk–shell particles (YSPs) were engineered using a tri-needle coaxial electrospraying technique enabling dual-mode (ultrasonic and magnetic resonance) imaging capability with specific multidrug compartments via an advanced single-step encapsulation process. YSPs comprised magnetic Fe3O4 nanoparticles (MNPs) embedded in the polymeric shell, an interfacing oil layer, and a polymeric core (i.e., composite shell–oil interface–polymeric core). The frequency of the ultrasound backscatter signal was modulated through YSP loading dosage, and both T1- and T2-weighted magnetic resonance imaging signal intensities were shown to decrease with increasing MNP content (YSP outer shell). Three fluorescent dyes (selected as model probes with varying hydrophobicities) were coencapsulated separately to confirm the YSP structure. Probe release profiles were tuned by varying power or frequency of an external auxiliary magnetic field (AMF, 0.7 mT (LAMF) or 1.4 mT (HAMF)). In addition, an “inversion” phenomenon for the AMF-enhanced drug release process was studied and is reported. A low YSP cytotoxicity (5 mg/mL) and biocompatibility (murine, L929) was confirmed. In summary, magnetic YSPs demonstrate timely potential as multifunctional theranostic agents for dual-imaging modality and magnetically controlled coactive delivery.