Digital Commons Network^™

Oxymatrine Loaded Crosslinked Pva Nanofibrous Scaffold: Design And Characterization And Anticancer Properties, Salahuddin Ahmed, Megan Keniry, Narcedalia Anaya-Barbosa, Victoria Padilla, Md Noushad Javed, Robert Gilkerson, Acharan S. Narula, Eman Ibrahim, Karen Lozano

Mechanical Engineering Faculty Publications and Presentations

This study focuses on the fabrication, characterization and anticancer properties of biocompatible and biodegradable composite nanofibers consisting of poly(vinyl alcohol) (PVA), oxymatrine (OM), and citric acid (CA) using a facile and high-yield centrifugal spinning process known as Forcespinning®. The effects of varying concentrations of OM and CA on fiber diameter and molecular crosslinking were investigated. The morphological and thermo-physical properties, as well as water absorption of the developed nanofiber-based mats were characterized using microscopical analysis, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. In vitro anti cancer studies were conducted with HCT116 colorectal cancer …

Recent Advances In Centrifugal Spinning And Their Applications In Tissue Engineering, Shaik Merkatur Hakim Marjuban, Musfira Rahman, Syeda Sharmin Duza, Mohammad Boshir Ahmed, Dinesh K. Patel, Md Saifur Rahman, Karen Lozano

Mechanical Engineering Faculty Publications and Presentations

Over the last decade, researchers have investigated the potential of nano and microfiber scaffolds to promote wound healing, tissue regeneration, and skin protection. The centrifugal spinning technique is favored over others due to its relatively straightforward mechanism for producing large quantities of fiber. Many polymeric materials have yet to be investigated in search of those with multifunctional properties that would make them attractive in tissue applications. This literature presents the fundamental process of fiber generation, and the effects of fabrication parameters (machine, solution) on the morphologies such as fiber diameter, distribution, alignment, porous features, and mechanical properties. Additionally, a brief …

Development Of Zinc Oxide/Hydroxyapatite/Poly(D,L-Lactic Acid) Fibrous Scaffold For Tissue Engineering Applications, Victoria Padilla-Gainza, Heriberto Rodríguez-Tobías, Graciela Morales, Antonio Ledezma-Pérez, Carmen Alvarado-Canché, Raúl Loera-Valencia, Cristóbal Rodríguez, Robert Gilkerson, Carlos Trevino De Leo, Karen Lozano

Mechanical Engineering Faculty Publications and Presentations

Scaffolds based on polymeric fibers represent an engaging biomedical device due to their particular morphology and similarity with extracellular matrices. The biggest challenge to use fibrous materials in the biomedical field is related to their favorable platform for the adhesion of pathogenic microorganisms. Therefore, their optimum performance not only depends on their bioactive potential but also on their antimicrobial properties. The aim of this work was the design of antimicrobial (zinc oxide, ZnO) and bioactive (hydroxyapatite, Hap) fibrous materials using poly(D, L-lactic acid) (PDLLA) as the polymer fiber substrate. Fiber based composite scaffolds were developed using the Forcespinning® technique. For …

Forcespun Polyvinylpyrrolidone/Copper And Polyethylene Oxide/Copper Composite Fibers And Their Use As Antibacterial Agents, Md Toukir Hasan, Ramiro Gonzalez, Ari Alexis Munoz, Luis Materon, Jason Parsons, Mataz Alcoutlabi

Mechanical Engineering Faculty Publications and Presentations

Copper nanoparticles (CuNPs) embedded in polyvinylpyrrolidone (PVP) and polyethylene oxide (PEO) fiber-matrices were prepared through centrifugal spinning of PVP/ethanol and PEO/aqueous solutions, respectively. The prime focus of the current study is to investigate the antibacterial activity of composite fibers against Escherichia coli (E. coli) and Bacillus cereus (B. cereus) bacteria. During the fiber formation, the centrifugal spinning parameters such as spinneret rotational speed, spinneret to collector distance, and relative humidity were carefully chosen to obtain long and continuous fibers. The structural and morphological analyses of both composite fibers were investigated using scanning electron microscopy, X-ray diffraction, …

Centrifugal Spinning And Characterization Of Co3o4 Coated Carbon Fibers, J. Ayala, D. Ramirez, Elizabeth M. Fletes, Helia Magali Morales, Jason Parsons, Mataz Alcoutlabi

Mechanical Engineering Faculty Publications and Presentations

Centrifugally spun polyacrylonitrile (PAN) microfibers surface-coated with Co3O4 nanoparticles (NPs) were prepared as precursors to produce coated Co3O4 carbon-composite fibers. The Co3O4/C composite fibers were obtained through a staged heating process during which the Co3O4PAN precursor fibers were stabilized over four hours at 200 °C, and subsequently the stabilized fibers were carbonized for six hours at 600 °C. The synthesis process presented in this work provides an effective strategy for the fabrication of surface coated-fiber materials, including composite fibers with good structure and morphology. The characterization of the Co3O4/C composite fibers was performed using SEM, EDS, XPS, XRD …

Processing-Structure-Property Relationships Of Biopolyester/Zinc Oxide Fibrous Scaffolds Engineered By Centrifugal Spinning, Victoria Padilla-Gainza, Heriberto Rodríguez-Tobías, Graciela Morales, Antonio Ledezma-Pérez, Carmen Alvarado-Canché, Cristobal Rodriguez, Robert Gilkerson, Karen Lozano

Mechanical Engineering Faculty Publications and Presentations

This study addresses the processing of nonwoven fibrous materials obtained by centrifugal spinning method, namely Forcespinning; a high yield and low production cost technique little explored in this field. Poly(D, L-lactic acid) (PDLLA) and poly(3-hydroxybutyrate) (PHB) were used as matrices and reinforced with zinc oxide nanoparticles (n-ZnO). The morphology, mechanical, and thermal performance of the developed composites were analyzed as well as the antibacterial effect of n-ZnO. Fibrous materials with n-ZnO concentrations of 1, 3, and 5 wt. % for PDLLA and 1 and 3 wt. % for PHB were evaluated. The results showed that the incorporation of n-ZnO produces …

Centrifugally Spun Α-Fe2o3/Tio2/Carbon Composite Fibers As Anode Materials For Lithium-Ion Batteries, Luis Zuniga, Gabriel Gonzalez, Roberto Orrostieta Chavez, Jason C. Myers, Timothy P. Lodge, Mataz Alcoutlabi

Mechanical Engineering Faculty Publications and Presentations

We report results on the electrochemical performance of flexible and binder-free α-Fe₂O₃/TiO₂/carbon composite fiber anodes for lithium-ion batteries (LIBs). The composite fibers were produced via centrifugal spinning and subsequent thermal processing. The fibers were prepared from a precursor solution containing PVP/iron (III) acetylacetonate/titanium (IV) butoxide/ethanol/acetic acid followed by oxidation at 200 °C in air and then carbonization at 550 °C under flowing argon. The morphology and structure of the composite fibers were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), …

Synthesis Of Multiwall Α-Fe2o3 Hollow Fibers Via A Centrifugal Spinning Technique, Mandana Akia, K. A. Mkhoyan, Karen Lozano

Mechanical Engineering Faculty Publications and Presentations

Highlights

• Hollow hematite (α-Fe2O3) fine fibers were fabricated via a simple, flexible, and scalable technique.

• An aqueous solution with iron precursor/polymer was used in the centrifugal spinning process

• Developed fibers show average wall thickness of 55 ± 15 nm and outer fiber diameter of 852 ± 86 nm

Abstract

Hollow hematite (α-Fe2O3) fine fibers with multiwall structure were synthesized by utilizing a centrifugal spinning technique. Aqueous solutions of polyvinyl pyrrolidone and iron (III) nitrate nonahydrate were prepared and spun into fibers. The precursor fibers were heat treated at 650 °C to form iron oxide fibers. Scanning electron micrographs revealed the …

Fabrication And Characterization Of Centrifugally Spun Poly(Acrylic Acid) Nanofibers, David De La Garza, Francisco De Santiago, Luis Materon, Mircea Chipara, Mataz Alcoutlabi

Mechanical Engineering Faculty Publications and Presentations

The production of poly(acrylic acid) (PAA) nanofibers by the centrifugal spinning of PAA solutions in water is reported. The effect of the spinneret rotational speed and concentration of PAA solutions on the diameter of nanofibers and on their quality (assessed by the absence of beads) is discussed. The main physical properties of PAA such as glass-transition temperature (Tg) are studied in detail and compared to the feature of the as-received homopolymer. It is shown that the glass-transition temperature of the bulk PAA and PAA nanofibers (as measured by differential scanning calorimetry) depends on the heating rate according …

Texas Sour Orange Juice Used In Scaffolds For Tissue Engineering, Mandana Akia, Nataly Salinas, Cristobal Rodriguez, Robert Gilkerson, Luis A. Materon, Karen Lozano

Mechanical Engineering Faculty Publications and Presentations

Fine fibers of polyhydroxybutyrate (PHB), a biopolymer, were developed via a centrifugal spinning technique. The developed fibers have an average diameter of 1.8 µm. Texas sour orange juice (SOJ) was applied as a natural antibacterial agent and infiltrated within the fibrous membranes. The antibacterial activity against common Gram-positive and Gram-negative bacteria (Staphylococcus aureus and Escherichia coli, respectively) was evaluated as well as cell adhesion and viability. The PHB/SOJ scaffolds showed antibacterial activity of up to 152% and 71% against S. aureus and E. coli, respectively. The cell studies revealed a suitable environment for cell growth and cell attachment. The outcome …

High-Throughput Production With Improved Functionality And Graphitization Of Carbon Fine Fibers Developed From Sodium Chloride-Polyacrylonitrile Precursors, Mandana Akia, Lee Cremar, Manuel Seas, Jahaziel Villarreal, Mataz Alcoutlabi, Karen Lozano

Mechanical Engineering Faculty Publications and Presentations

Fine polyacrylonitrile (PAN) fibers were produced through a scalable centrifugal spinning process. Sodium chloride (NaCl) was added to the PAN-dimethylformamide solution to decrease the surface tension and consequently promote a decrease in fiber diameter while increasing the fiber output. The fiber preparation process involved the centrifugal spinning of the PAN-based solution; developed fibers were stabilized in air at 240°C followed by carbonization at 800°C under a Nitrogen atmosphere. The addition of sodium chloride to the PAN solution led to a 37% decrease in the carbon fiber diameter. The carbon fibers were analyzed by scanning electron microcopy, transmission electron microscopy (TEM), …

High-Throughput Production With Improved Functionality And Graphitization Of Carbon Fine Fibers Developed From Sodium Chloride-Polyacrylonitrile Precursors, Mandana Akia, Lee Cremar, Manuel Seas, Jahaziel Villarreal, Alejandra Valdez, Mataz Alcoutlabi, Karen Lozano

Mechanical Engineering Faculty Publications and Presentations

Fine polyacrylonitrile (PAN) fibers were produced through a scalable centrifugal spinning process. Sodium chloride (NaCl) was added to the PAN-dimethylformamide solution to decrease the surface tension and consequently promote a decrease in fiber diameter while increasing the fiber output. The fiber preparation process involved the centrifugal spinning of the PAN-based solution; developed fibers were stabilized in air at 240°C followed by carbonization at 800°C under a Nitrogen atmosphere. The addition of sodium chloride to the PAN solution led to a 37% decrease in the carbon fiber diameter. The carbon fibers were analyzed by scanning electron microcopy, transmission electron microscopy (TEM), …