Biomedical Engineering and Bioengineering Commons^™

Silver Nanoparticle Coated Bioactive Glasses - Composites With Dex/Cmc Hydrogels: Characterization, Solubility, And In Vitro Biological Studies, Anthony W. Wren, Pegah Hassanzadeh, Lana M. Placek, Timothy J. Keenan, Aisling Coughlan, Lydia R. Boutelle, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Silver (Ag) coated bioactive glass particles (Ag-BG) were formulated and compared to uncoated controls (BG) in relation to glass characterization, solubility and microbiology. X-ray diffraction (XRD) confirmed a crystalline AgNP surface coating while ion release studies determined low Ag release (/L). Cell culture studies presented increased cell viability (127 and 102%) with lower liquid extract (50 and 100 ml/ml) concentrations. Antibacterial testing of Ag-BG in E. coli, S. epidermidis and S. aureus significantly reduced bacterial cell viability by 60-90%. Composites of Ag-BG/CMC-Dex Hydrogels were formulated and characterized. Agar diffusion testing was conducted where Ag-BG/hydrogel composites produced the largest inhibition zones …

Bioactive Glass Reinforced Elastomer Composites For Skeletal Regeneration: A Review, Ehsan Zeimaran, Sara Pourshahrestani, Ivan Djordjevic, Belinda Pingguan-Murphy, Nahrizul Adib Kadri, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Biodegradable elastomers have clinical applicability due to their biocompatibility, tunable degradation and elasticity. The addition of bioactive glasses to these elastomers can impart mechanical properties sufficient for hard tissue replacement. Hence, a composite with a biodegradable polymer matrix and a bio glass filler can offer a method of augmenting existing tissue. This article reviews the applications of such composites for skeletal augmentation.

Matrix Compliance And The Regulation Of Cytokinesis, Savitha Sambandamoorthy, Shomita Mathew-Steiner, Scott Varney, Jonathan M. Zuidema, Ryan J. Gilbert, Livingston De Van Water, Susan E. Laflamme

Chemical and Biochemical Engineering Faculty Research & Creative Works

Integrin-mediated cell adhesion to the ECM regulates many physiological processes in part by controlling cell proliferation. It is well established that many normal cells require integrin-mediated adhesion to enter S phase of the cell cycle. Recent evidence indicates that integrins also regulate cytokinesis. Mechanical properties of the ECM can dictate entry into S phase; however, it is not known whether they also can affect the successful completion of cell division. To address this issue, we modulated substrate compliance using fibronectin-coated acrylamide-based hydrogels. Soft and hard substrates were generated with approximate elastic moduli of 1600 and 34,000 Pascals (Pa) respectively. Our …

Astrocyte Response To Nanoscale Topography On Anodized Alumina Surfaces, D. Ganguly, C. D.L. Johnson, D. A. Borca-Tasciuc, R. J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Astrocytes are one of the most important and abundant resident glial cells of the central nervous system (CNS). They play a critical role in the foreign body response, by participating in the formation of the glial scar sunouncling implants. As part of the effort to minimize the foreign body response, biomaterials strategies einployiug engineered surfaces topographies are being explored. In this context, we have investigated the response of astrocytes to surface topography of alumiua, a material used in CNS applications. Specifically, astrocytes were seeded oil alumina surfaces with nanopores 20 nm and 100 nm in diameter, respectively. Pore-free alumina …

Effects Of Strontium Substitution On Bioactivity Of Hydroxyapatite, Chokchai Yatongchai, Lana M. Placek, Mark R. Towler, Anthony W. Wren

Chemical and Biochemical Engineering Faculty Research & Creative Works

Effect of strontium (Sr) substitution on bioactivity of hydroxyapatite (HA) was investigated. The substitution of Sr²⁺ for Ca²⁺ in the HA lattice increases biodegradability of Sr-substituted HA (Sr-HA) and accelerates the formation of apatite crystals on the Sr-HA surface. Moreover, the dissolution products from HA and Sr-HA samples are not cyto-toxic.

Analysis Of Neurite Outgrowth On Electrospun Fiber Scaffolds In The Presence Of Blebbistatin And Paclitaxel, A. R. D'Amato, N. J. Schaub, C. D.L. Johnson, J. Cardenas, R. J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

In an attempt to increase the rate of neurite extension from E9 chick embryo dorsal root ganglion (DRG) on electro spun fiber scaffolds we experimented with two drugs that have been used previously to affect neuronal growth. Blebbistatin and paclitaxel were added to DRG cultured on electro spun fibers in an attempt to increase the rate of neurite extension along fibrous scaffolds. Blebbistatin increased the length of neurites extending from the DRG explant in comparison to the drug-free control group. In contrast, paclitaxel completely eliminated all neurite extension from the DRG explant when compared to the control. A third treatment …

Initial Astrocyte Response To Electrospun Poly-L-Lactic Acid Fibers Of Varying Nanoscale Diameters, C. D.L. Johnson, J. M. Zuidema, G. P. Desmond, A. R. D'Amato, N. J. Schaub, R. J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

We hypothesized that fiber diameter within an electro spun fiber scaffold would affect astrocyte elongation and maturation. To examine the relationship, astrocytes were seeded on 400nm and 800nm diameter electro spun PLLA fibers. Immunohistochemistry was used to monitor cell morphology, and GLT-1 expression over the first 96 hours after seeding. The results indicate that astrocytes extended along the primary axis of the 800nm fibers more rapidly than astrocytes seeded on fibers of half the size. While GLT-1 was expressed diffusely throughout the surface of the astrocytes, elongated cell processes exhibited dense regions of GLT-1. These results show that 800nm fibers …

Significant Degradability Enhancement In Multilayer Coating Of Polycaprolactone-Bioactive Glass/Gelatin-Bioactive Glass On Magnesium Scaffold For Tissue Engineering Applications, Mostafa Yazdimamaghani, Mehdi Razavi, Daryoosh Vashaee, Venkata Raveendra Pothineni, Jayakumar Rajadas, Lobat Tayebi

Chemical and Biochemical Engineering Faculty Research & Creative Works

Magnesium (Mg) is a promising candidate to be used in medical products especially as bone tissue engineering scaffolds. The main challenge for using Mg in biomedical applications is its high degradation rate in the body. For this reason, in this study, a multilayer polymeric layer composed of polycaprolactone (PCL) and gelatin (Gel) reinforced with bioactive glass (BaG) particles has been applied on the surface of Mg scaffolds. The materials characteristics of uncoated Mg scaffold, Mg scaffold coated only with PCL-BaG and Mg scaffold coated with PCL-BaG and Gel-BaG have been analyzed and compared in detail. Scanning electron microscope (SEM) equipped …

Surface Modification Of Biodegradable Porous Mg Bone Scaffold Using Polycaprolactone/Bioactive Glass Composite, Mostafa Yazdimamaghani, Mehdi Razavi, Daryoosh Vashaee, Lobat Tayebi

Chemical and Biochemical Engineering Faculty Research & Creative Works

A reduction in the degradation rate of magnesium (Mg) and its alloys is in high demand to enable these materials to be used in orthopedic applications. For this purpose, in this paper, a biocompatible polymeric layer reinforced with a bioactive ceramic made of polycaprolactone (PCL) and bioactive glass (BG) was applied on the surface of Mg scaffolds using dip-coating technique under low vacuum. The results indicated that the PCL-BG coated Mg scaffolds exhibited noticeably enhanced bioactivity compared to the uncoated scaffold. Moreover, the mechanical integrity of the Mg scaffolds was improved using the PCL-BG coating on the surface. The stable …

Nebulized Solvent Ablation Of Aligned Plla Fibers For The Study Of Neurite Response To Anisotropic-To-Isotropic Fiber/Film Transition (Afft) Boundaries In Astrocyte-Neuron Co-Cultures, Jonathan M. Zuidema, Gregory P. Desmond, Christopher J. Rivet, Kathryn R. Kearns, Deanna M. Thompson, Ryan J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Developing robust invitro models of in vivo environments has the potential to reduce costs and bring new therapies from the bench top to the clinic more efficiently. This study aimed to develop a biomaterial platform capable of modeling isotropic-to-anisotropic cellular transitions observed in vivo, specifically focusing on changes in cellular organization following spinal cord injury. In order to accomplish this goal, nebulized solvent patterning of aligned, electro spun poly-. l-lactic acid (PLLA) fiber substrates were developed. This method produced a clear topographic transitional boundary between aligned PLLA fibers and an isotropic PLLA film region. Astrocytes were then seeded on these …

Fabrication And Characterization Of Poly(Octanediol Citrate)/Gallium-Containing Bioglass Microcomposite Scaffolds, Ehsan Zeimaran, Sara Pourshahrestani, Belinda Pingguan-Murphy, Nahrizul Adib Kadri, Hussin A. Rothan, Rohana Yusof, Mark R. Towler, Ivan Djordjevic

Chemical and Biochemical Engineering Faculty Research & Creative Works

Bone can be affected by osteosarcomae requiring surgical excision of the tumor as part of the treatment regime. Complete removal of cancerous cells is difficult and conventionally requires the removal of a margin of safety around the tumor to offer improved patient prognosis. This work considers a novel series of composite scaffolds based on poly (octanediol citrate) (POC) impregnated with gallium-based bioglass microparticles for possible incorporation into bone following tumor removal. The objective of this research was to fabricate and characterize these scaffolds and subsequently report on their mechanical and biological properties. The porous micro composite scaffolds with various concentrations …

A Glass Polyalkenoate Cement Carrier For Bone Morphogenetic Proteins, Adel M.F. Alhalawani, Omar Rodriguez, Declan J. Curran, Russell Co, Sean Kieran, Saad Arshad, Timothy J. Keenan, Anthony W. Wren, Gazelle Crasto, Sean A.F. Peel, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

This work considers a glass polyalkenoate cement (GPC)-based carrier for the effective delivery of bone morphogenetic proteins (BMPs) at an implantation site. A 0.12 CaO–0.04 SrO–0.36 ZnO–0.48 SiO₂ based glass and poly(acrylic acid) (PAA, Mw 213,000) were employed for the fabrication of the GPC. The media used for the water source in the GPC reaction was altered to produce a series of GPCs. The GPC liquid media was either 100 % distilled water with additions of albumin at 0, 2, 5 and 8 wt% of the glass content, 100 % formulation buffer (IFB), and 100 % BMP (150 µg …

Investigating The Solubility And Cytocompatibility Of Cao-Na2o-Sio2/Tio2 Bioactive Glasses, Anthony W. Wren, Aisling Coughlan, Courtney M. Smith, Sarah P. Hudson, Fathima R. Laffir, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

This study aims to investigate the solubility of a series of titanium (TiO₂)-containing bioactive glasses and their subsequent effect on cell viability. Five glasses were synthesized in the composition range SiO₂-Na₂O-CaO with 5 mol % of increments TiO₂ substituted for SiO₂. Glass solubility was investigated with respect to (1) exposed surface area, (2) particle size, (3) incubation time, and (4) compositional effects. Ion release profiles showed that sodium (Na⁺) presented high release rates after 1 day and were unchanged between 7 and 14 days. Calcium (Ca²⁺) release …

Formulation Of Benzoxaborole Drugs In Plla: From Materials Preparation To In Vitro Release Kinetics And Cellular Assays, Saad Sene, Joshua Mclane, Nicholas Schaub, Sylvie Bégu, P. Hubert Mutin, Lee Ligon, Ryan J. Gilbert, Danielle Laurencin

Chemical and Biochemical Engineering Faculty Research & Creative Works

Benzoxaboroles are a family of organoboron molecules, which have been finding over the past few years an increasing number of biological applications, notably for the design of new drugs. Given that these molecules are still relatively new in the biomedical context, very few investigations regarding their formulation have been reported to date. Here, a complete study on the formulation of benzoxaboroles in a biopolymer, poly-l-lactic acid (PLLA), is reported. The incorporation of two small benzoxaboroles, namely the simplest benzoxaborole molecule (BBzx) and the antifungal drug tavaborole (AN2690), inside PLLA films was investigated. Different variations in the film composition and texture …

Astrocytes Increase Atp Exocytosis Mediated Calcium Signaling In Response To Microgroove Structures, Ajay V. Singh, Michael Raymond, Fabiano Pace, Anthony Certo, Jonathan M. Zuidema, Christopher A. Mckay, Ryan J. Gilbert, X. Lucas Lu, Leo Q. Wan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Following central nervous system (CNS) injury, activated astrocytes form glial scars, which inhibit axonal regeneration, leading to long-term functional deficits. Engineered nanoscale scaffolds guide cell growth and enhance regeneration within models of spinal cord injury. However, the effects of micro-/nano size scaffolds on astrocyte function are not well characterized. In this study, a high throughput (HTP) microscale platform was developed to study astrocyte cell behavior on micropatterned surfaces containing 11/4m spacing grooves with a depth of 250 or 500â €...nm. Significant changes in cell and nuclear elongation and alignment on patterned surfaces were observed, compared to on flat surfaces. The …

Effect Of Nitrogen On Properties Of Na2o-Cao-Sro-Zno-Sio2 Glasses, Ahmed Bachar, Cyrille Mercier, Arnaud Tricoteaux, Jean Christophe Hornez, Anne Leriche, Claudine Follet, Bertrand Revel, Stuart Hampshire, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Glasses in the Na₂O-CaO-SrO-ZnO-SiO₂ system have previously been investigated for suitability as a reagent in Al-free glass polyalkenoate cements (GPCs). These materials have many properties that offer potential in orthopedics. However, their applicability has been limited, to date, because of their poor strength. This study was undertaken with the aim of increasing the mechanical properties of a series of these Zn-based GPC glasses by doping with nitrogen to give overall compositions of: 10Na₂O-10CaO-20SrO-20ZnO-(40-3x)SiO₂-xSi₃N₄ (x is the no. of moles of Si₃N₄). The density, glass-transition temperature, hardness, …

Cell Infiltration Into A 3d Electrospun Fiber And Hydrogel Hybrid Scaffold Implanted In The Brain, Christopher J. Rivet, Kun Zhou, Ryan J. Gilbert, David I. Finkelstein, John S. Forsythe

Chemical and Biochemical Engineering Faculty Research & Creative Works

Tissue engineering scaffolds are often designed without appropriate consideration for the translational potential of the material. Solid scaffolds implanted into central nervous system (CNS) tissue to promote regeneration may require tissue resection to accommodate implantation. Or alternatively, the solid scaffold may be cut or shaped to better fit an irregular injury geometry, but some features of the augmented scaffold may fail to integrate with surrounding tissue reducing regeneration potential. To create a biomaterial able to completely fill the irregular geometry of CNS injury and yet still provide sufficient cell migratory cues, an injectable, hybrid scaffold was created to present the …

Reduced Astrocyte Viability At Physiological Temperatures From Magnetically Activated Iron Oxide Nanoparticles, Nicholas J. Schaub, Deniz Rende, Yuan Yuan, Ryan J. Gilbert, Diana Andra Borca-Tasciuc

Chemical and Biochemical Engineering Faculty Research & Creative Works

Superparamagnetic iron oxide nanoparticles (SPIONs) can generate heat when subjected to an alternating magnetic field (AMF). In the European Union, SPIONs actuated by AMF are used in hyperthermia treatment of glioblastoma multiforme, an aggressive form of brain cancer. Current data from clinical trials suggest that this therapy improves patient life expectancy, but their effect on healthy brain cells is virtually unknown. Thus, a viability study involving SPIONs subjected to an AMF was carried out on healthy cortical rat astrocytes, the most abundant cell type in the mammalian brain. The cells were cultured with amino silane- or starch-coated SPIONs with or …

Processing And Mechanical Testing Of Strontium-Substituted Hydroxyapatite/Glass Composites, Chokchai Yatongchai, Mark R. Towler, Anthony W. Wren

Chemical and Biochemical Engineering Faculty Research & Creative Works

Sr-HA/Glass composites were produced. Phase composition of composites was evaluated. Their physical and mechanical properties were determined. Sintered composites mainly consisted of Sr-HA/β-TCP, or β-TCP/Ca₂ZnSi₂O₇. The composites had porosity up to 4 times those of undoped Sr-HA. Compared to undoped Sr-HA, the Sr-HA/Glass composites had lower biaxial flexural strength and hardness. The Weibull modulus for the composites ranged from 2.77 to 18.74.

Conducting Scaffolds For Liver Tissue Engineering, Armin Tahmasbi Rad, Naushad Ali, Hari Shankar R. Kotturi, Mostafa Yazdimamaghani, Jim Smay, Daryoosh Vashaee, Lobat Tayebi

Chemical and Biochemical Engineering Faculty Research & Creative Works

It is known that there is a correlation between a cell membrane potential and the proliferation of the cell. The high proliferation capacity of liver cells can also be attributed to its specific cell membrane potential as liver cell is recognized as one of the most depolarized of all differentiated cells. We hypothesized that this phenomenon can be emphasized by growing liver cells in conducting scaffolds that can increase the electrical communication among the cells. In this article, using tissue engineering techniques, we grew hepatocyte cells in scaffolds with various compositions. It was found that the scaffolds containing conducting polymer …

Development And Degradation Behavior Of Magnesium Scaffolds Coated With Polycaprolactone For Bone Tissue Engineering, Mostafa Yazdimamaghani, Mehdi Razavi, Daryoosh Vashaee, Lobat Tayebi

Chemical and Biochemical Engineering Faculty Research & Creative Works

Rapid degradation of magnesium (Mg) alloys is the major drawback preventing these materials from being applicable as tissue engineering scaffolds. In order to resolve this issue, in this paper, porous Mg scaffolds coated by polycaprolactone (PCL) were synthesized and their material properties and in vitro biodegradation were fully examined. The results indicated that PCL coating can significantly enhance the compressive strength and degradation resistance of Mg scaffolds. We showed that while the uncoated Mg scaffold degrades completely (100% weight loss) after 72 h, the degradation (weight loss) of the Mg scaffolds coated by 3% and 6% PCL is only 36% …

Green Synthesis Of A New Gelatin-Based Antimicrobial Scaffold For Tissue Engineering, Mostafa Yazdimamaghani, Daryoosh Vashaee, Senait Assefa, Mitra Shabrangharehdasht, Armin Tahmasbi Rad, Margaret A. Eastman, Kenneth J. Walker, Sundar V. Madihally, Gerwald A. Köhler, Lobat Tayebi

Chemical and Biochemical Engineering Faculty Research & Creative Works

With the aim of developing appropriate scaffolds for tissue engineering to suppress the formation of biofilms, an effective one-pot process was applied in this study to produce scaffolds with inherent antibacterial activity. A new method to synthesize genipin-crosslinked gelatin/nano silver scaffolds with "green" in situ formation of silver nanoparticles by heat treatment is presented in this paper. In this procedure, toxic solvents, reducing agents, and stabilizing agents are avoided. UV-visible absorption spectra of the synthesized gelatin/nano silver solutions were obtained immediately and three months after the synthesis revealing the presence and high stability of the silver nanoparticles. The TEM of …

An Injectable, Calcium Responsive Composite Hydrogel For The Treatment Of Acute Spinal Cord Injury, Christopher A. Mckay, Rebecca D. Pomrenke, Joshua S. Mclane, Nicholas J. Schaub, Elise K. Desimone, Lee A. Ligon, Ryan J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Immediately following spinal cord injury, further injury can occur through several secondary injury cascades. As a consequence of cell lysis, an increase in extracellular Ca²⁺ results in additional neuronal loss by inducing apoptosis. Thus, hydrogels that reduce extracellular Ca²⁺ concentration may reduce secondary injury severity. The goal of this study was to develop composite hydrogels consisting of alginate, chitosan, and genipin that interact with extracellular Ca²⁺ to enable in situ gelation while maintaining an elastic modulus similar to native spinal cord (∼1000 Pa). It was hypothesized that incorporation of genipin and chitosan would regulate hydrogel electrostatic characteristics …

Enhanced Glt-1 Mediated Glutamate Uptake And Migration Of Primary Astrocytes Directed By Fibronectin-Coated Electrospun Poly-L-Lactic Acid Fibers, Jonathan M. Zuidema, María C. Hyzinski-García, Kristien Van Vlasselaer, Nicholas W. Zaccor, George E. Plopper, Alexander A. Mongin, Ryan J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Bioengineered fiber substrates are increasingly studied as a means to promote regeneration and remodeling in the injured central nervous system (CNS). Previous reports largely focused on the ability of oriented scaffolds to bridge injured regions and direct outgrowth of axonal projections. In the present work, we explored the effects of electro spun microfibers on the migration and physiological properties of brain astroglial cells. Primary rat astrocytes were cultured on either fibronectin-coated poly-l-lactic acid (PLLA) films, fibronectin-coated randomly oriented PLLA electro spun fibers, or fibronectin-coated aligned PLLA electro spun fibers. Aligned PLLA fibers strongly altered astrocytic morphology, orienting cell processes, actin …

Degradable Borate Glass Polyalkenoate Cements, L. Shen, A. Coughlan, Mark R. Towler, M. Hall

Chemical and Biochemical Engineering Faculty Research & Creative Works

Glass polyalkenoate cements (GPCs) containing aluminum-free borate glasses having the general composition Ag₂O-Na₂O-CaO-SrO-ZnO- TiO₂-B₂O₃ were evaluated in this work. An initial screening study of sixteen compositions was used to identify regions of glass formation and cement compositions with promising rheological properties. The results of the screening study were used to develop four model borate glass compositions for further study. A second round of rheological experiments was used to identify a preferred GPC formulation for each model glass composition. The model borate glasses containing higher levels of TiO₂ (7.5 mol %) …

Investigating The Effect Of Sio2-Tio2-Cao-Na 2o-Zno Bioactive Glass Doped Hydroxyapatite: Characterisation And Structural Evaluation, Chokchai Yatongchai, Anthony W. Wren, Declan J. Curran, Stuart Hampshire, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

The effects of increasing bioactive glass additions,

SiO₂-TiO₂-CaO-Na₂O-ZnO up to 25 wt% in increments of 5 wt%, on the physical and mechanical properties of hydroxyapatite (HA) sintered at 900, 1000, 1100 and 1200°C for 2 h was investigated. Increasing both the glass content and the temperature resulted in increased HA decomposition. This resulted in the formation of a number of bioactive phases. However the presence of the liquidus glass phase did not result in increased densification levels. At 1000 and 1100°C the additions of 5 wt% glass resulted in a decrease in density which …

A Protocol For Rheological Characterization Of Hydrogels For Tissue Engineering Strategies, Jonathan M. Zuidema, Christopher J. Rivet, Ryan J. Gilbert, Faith A. Morrison

Chemical and Biochemical Engineering Faculty Research & Creative Works

Hydrogels are studied extensively for many tissue engineering applications, and their mechanical properties influence both cellular and tissue compatibility. However, it is difficult to compare the mechanical properties of hydrogels between studies due to a lack of continuity between rheological protocols. This study outlines a straightforward protocol to accurately determine hydrogel equilibrium modulus and gelation time using a series of rheological tests. These protocols are applied to several hydrogel systems used within tissue engineering applications: agarose, collagen, fibrin, Matrigel™, and methylcellulose. The protocol is outlined in four steps: (1) Time sweeps to determine the gelation time of the hydrogel. (2) …

Effect Of Magnetic Nanoparticle Heating On Cortical Neuron Viability, Christopher J. Rivet, Yuan Yuan, Ryan J. Gilbert, Diana Andra Borca-Tasciuc

Chemical and Biochemical Engineering Faculty Research & Creative Works

Purpose: Superparamagnetic iron oxide nanoparticles are currently approved for use as an adjunctive treatment to glioblastoma multiforme radiotherapy. Radio frequency stimulation of the nanoparticles generates localized hyperthermia, which sensitizes the tumor to the effects of radiotherapy. Clinical trials reported thus far are promising, with an increase in patient survival rate; however, what are left unaddressed are the implications of this technology on the surrounding healthy tissue. Methods and materials: Amino silane-coated iron oxide nanoparticles suspended in culture medium were applied to chick embryonic cortical neuron cultures. Cultures were heated to 37 °C or 45 °C by an induction coil system …

3d Conductive Nanocomposite Scaffold For Bone Tissue Engineering, Aref Shahini, Mostafa Yazdimamaghani, Kenneth J. Walker, Margaret A. Eastman, Hamed Hatami-Marbini, Brenda J. Smith, John L. Ricci, Sundar V. Madihally, Daryoosh Vashaee, Lobat Tayebi

Chemical and Biochemical Engineering Faculty Research & Creative Works

Bone healing can be significantly expedited by applying electrical stimuli in the injured region. Therefore, a three-dimensional (3D) ceramic conductive tissue engineering scaffold for large bone defects that can locally deliver the electrical stimuli is highly desired. In the present study, 3D conductive scaffolds were prepared by employing a biocompatible conductive polymer, ie, poly(3,4-ethylenedioxythiophene) poly (4-styrene sulfonate) (PEDOT:PSS), in the optimized nanocomposite of gelatin and bioactive glass. For in vitro analysis, adult human mesenchymal stem cells were seeded in the scaffolds. Material characterizations using hydrogen-1 nuclear magnetic resonance, in vitro degradation, as well as thermal and mechanical analysis showed that …

Characteristics Of Glass Ionomer Cements Composed Of Glass Powders In Cao-Sro-Zno-Sio2 System Prepared By Two Different Synthetic Routes, Ill Yong Kim, Chikara Ohtsuki, Aisling Coughlan, Lana Placek, Anthony W. Wren, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Glass ionomer cements (GICs) are composed of an acid degradable glass, polyacrylic acid and water. Sol-gel processing to prepare the glass phase has certain advantages, such as the ability to employ lower synthesis temperatures than melt quenching and glasses that are reported to have higher purity. A previous study reported the effects of glass synthesis route on GIC fabrication. However, in that study, the sol-gel derived glass exhibited a reduced concentration of cations. This study investigates increasing the cation content of a sol-gel derived glass, 12CaO·4SrO·36ZnO·48SiO₂ (molar ratio) by heating before aging to reduce dissolution of cations. This glass …