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Biomedical Engineering and Bioengineering Commons™

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Biochemical and Biomolecular Engineering

2010

Articles 1 - 10 of 10

Full-Text Articles in Biomedical Engineering and Bioengineering

Comparison Of Antibacterial Properties Of Commercial Bone Cements And Fillers With A Zinc-Based Glass Polyalkenoate Cement, A. W. Wren, N. M. Cummins, Mark R. Towler Oct 2010

Comparison Of Antibacterial Properties Of Commercial Bone Cements And Fillers With A Zinc-Based Glass Polyalkenoate Cement, A. W. Wren, N. M. Cummins, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Postoperative infection following invasive surgical procedures is a significant cause for concern, particularly in spinal reconstructive surgery. The objective of this study is to compare the antibacterial efficacy of a novel zinc-based glass polyalkenoate cement (Zn-GPC) based on 0.04SrO-0.12CaO-0.36ZnO- 0.48SiO2 glass, to a number of commercially available bone cements and fillers including Simplex P + Tobramycin (STob), Spineplex (Spine) and Novabone Putty (NPut). The agar diffusion test was performed on each material against Escherichia coli, Staphlococcus epidermidis, Pseudomonas aeruginosa and Staphlococcus Aureus. STob was found to produce large inhibition zones in each …

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The Effect Of Ionic Dissolution Products Of Ca-Sr-Na-Zn-Si Bioactive Glass On In Vitro Cytocompatibility, S. Murphy, A. W. Wren, Mark R. Towler, D. Boyd Oct 2010

The Effect Of Ionic Dissolution Products Of Ca-Sr-Na-Zn-Si Bioactive Glass On In Vitro Cytocompatibility, S. Murphy, A. W. Wren, Mark R. Towler, D. Boyd

Chemical and Biochemical Engineering Faculty Research & Creative Works

Many commercial bone grafts cannot regenerate healthy bone in place of diseased bone. Bioactive glasses have received much attention in this regard due to the ability of their ionic dissolution products to promote cell proliferation, cell differentiation and activate gene expression. Through the incorporation of certain ions, bioactive glasses can become therapeutic for specific pathological situations. Calcium-strontium-sodium-zinc-silicate glass bone grafts have been shown to release therapeutic levels of zinc and strontium, however the in vitro compatibility of these materials is yet to be reported. In this study, the in vitro cytocompatibility of three different calcium-strontium-sodium-zinc-silicate glasses was examined as a …

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A Spectroscopic Investigation Into The Setting And Mechanical Properties Of Titanium Containing Glass Polyalkenoate Cements, A. W. Wren, A. Kidari, N. M. Cummins, Mark R. Towler Aug 2010

A Spectroscopic Investigation Into The Setting And Mechanical Properties Of Titanium Containing Glass Polyalkenoate Cements, A. W. Wren, A. Kidari, N. M. Cummins, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Titanium (Ti) implants are extensively used in a number of biomedical and dental applications. This work introduces Ti into the glass phase of a zinc-based glass polyalkenoate cement (GPC) and investigates changes in handling and mechanical properties considering two molecular weight polyacrylic acids (PAA), E9 and E11. Considering the handling properties, the working time (Tw) increased from 50 sE9, 32 sE11 (BT 101, Ti-free) to 169 sE9, 74 sE11 with TW-Z (highest Ti content), respectively. The setting time (Ts) increased from 76 sE9, 47 sE11 (BT 101) …

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The Effect Of Adding Organic Polymers On The Handling Properties, Strengths And Bioactivity Of A Ca-Sr-Zn-Si Glass Polyalkenoate Cement, A. W. Wren, N. M. Cummins, A. Coughlan, Mark R. Towler Jul 2010

The Effect Of Adding Organic Polymers On The Handling Properties, Strengths And Bioactivity Of A Ca-Sr-Zn-Si Glass Polyalkenoate Cement, A. W. Wren, N. M. Cummins, A. Coughlan, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

This work demonstrates the addition of a number of naturally occurring proteins/polymers to a zinc-based glass polyalkenoate cements (GPCs). Chitin (Chi.), collagen (Col.), cysteine (Cys.) and keratin (Ker.) were added with the intention of improving the bioactivity of this cement. Initial testing involved characterization of the glass with X-ray diffraction (XRD) and differential thermal analysis (DTA) before and after sterilization with γ-irradiation. No significant changes occurred as a result of sterilization. Handling properties of the modified cements were not significantly different from those of the control, BT 101 (Working Tw-36s, and setting time Ts-70 …

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Influence Of Morphology And Processing On Xps Characterisation Of Sro-Ca-Zno-Sio2 Glass, F. R. Laffir, A. W. Wren, Mark R. Towler Jun 2010

Influence Of Morphology And Processing On Xps Characterisation Of Sro-Ca-Zno-Sio2 Glass, F. R. Laffir, A. W. Wren, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

A study was conducted to demonstrate the influence of morphology and processing on X-ray photoelectron spectroscopic (XPS) characterization SrO-Ca-ZnO-SiO2 glass. The glass formulation being investigated was originally synthesized for developing a novel glass polyalkenoate cement (GPC). High resolution photoelectron spectra of Zn 2p, Ca 2p, Sr 3d, Si 2p, O 1s, and C 1s were recorded for the different forms of glass. It was observed that there was preferential enrichment of Zn2+ with an increase in the proportion of NBO for the investigated BT101 glass. The relative atomic concentration of Zn in BT101 glass was high and resulted …

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Synthesis Of An Endothelial Cell Mimicking Surface Containing Thrombomodulin And Endothelial Protein C Receptor, Karl E. Kador Apr 2010

Synthesis Of An Endothelial Cell Mimicking Surface Containing Thrombomodulin And Endothelial Protein C Receptor, Karl E. Kador

Department of Chemical and Biomolecular Engineering: Theses and Student Research

Synthetic materials for use in blood contacting applications have been studied for many years with limited success. One of the main areas of need for these materials is the design of synthetic vascular grafts for use in the hundreds of thousands of patients who have coronary artery bypass grafting, many without suitable veins for autologous grafts. The design of these grafts is constrained by two common modes of failure, the formation of intimal hyperplasia (IH) and thrombosis. IH formation has been previously linked to a mismatching of the mechanical properties of the graft and has been overcome by creating grafts …

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Mechanical Properties Of Hydroxyapatite-Zirconia Compacts Sintered By Two Different Sintering Methods, Declan J. Curran, Thomas J. Fleming, Mark R. Towler, Stuart Hampshire Apr 2010

Mechanical Properties Of Hydroxyapatite-Zirconia Compacts Sintered By Two Different Sintering Methods, Declan J. Curran, Thomas J. Fleming, Mark R. Towler, Stuart Hampshire

Chemical and Biochemical Engineering Faculty Research & Creative Works

Microwave sintering is traditionally employed to reduce the sintering temperature required to densify powder compacts. The effect of microwave heating on hydroxyapatite (HA)-zirconia (ZrO2) green bodies has been investigated in order to understand how microwave energy may affect the physical and mechanical properties of the resultant densified composites. Laboratory synthesised nano-sized HA and a commercial nano-sized ZrO2 powder have been ball milled to create mixtures containing 0-5 wt% ZrO2 loadings. Compacts were microwave sintered at either 700, 1000 or 1200°C with a 1 h hold time. Comparative firings were also performed in a resistive element furnace …

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Reversible Addition - Fragmentation Chain Transfer In Microemulsions: Effect Of Chain Transfer Agent Aqueous Solubility, Jennifer M. O'Donnell, Eric W. Kaler Jan 2010

Reversible Addition - Fragmentation Chain Transfer In Microemulsions: Effect Of Chain Transfer Agent Aqueous Solubility, Jennifer M. O'Donnell, Eric W. Kaler

Jennifer M. Heinen

Microemulsion polymerizations are attractive for investigating compartmentalization effects in heterogeneous reversible addition - fragmentation chain transfer (RAFT) polymerizations because the propagating radicals are segregated into surfactant stabilized polymer particles, which drastically reduces the effects of biradical termination, Also, microemulsion polymerizations do not involve the large monomer droplets that are present in emulsion and miniemulsion polymerizations. RAFT microemulsion polymerizations of butyl aery late with a high water solubility chain transfer agent, methyl-2-(O-ethylxanthyl)propionate (MOEP), and a low water solubility chain transfer agent, methyl-2-(O-dodecylxanthyl)propionate (MODP), were investigated to determine the effect of chain transfer agent compartmentalization on the control of the polymerization. The …

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Nonequilibrium Thermodynamics Modeling Of Coupled Biochemical Cycles In Living Cells, Yaşar Demirel Jan 2010

Nonequilibrium Thermodynamics Modeling Of Coupled Biochemical Cycles In Living Cells, Yaşar Demirel

Yaşar Demirel Publications

Living cells represent open, nonequilibrium, self organizing, and dissipative systems maintained with the continuous supply of outside and inside material, energy, and information flows. The energy in the form of adenosine triphosphate is utilized in biochemical cycles, transport processes, protein synthesis, reproduction, and performing other biological work. The processes in molecular and cellular biological systems are stochastic in nature with varying spatial and time scales, and bounded with conservation laws, kinetic laws, and thermodynamic constraints, which should be taken into account by any approach for modeling biological systems. In component biology, this review focuses on the modeling of enzyme kinetics …

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Evaluation Of Two Novel Aluminum-Free, Zinc-Based Glass Polyalkenoate Cements As Alternatives To Pmma Bone Cement For Use In Vertebroplasty And Balloon Kyphoplasty, Gladius Lewis, Mark R. Towler, Daniel Boyd, Matthew J. German, Anthony W. Wren, Owen M. Clarkin, Andrew Yates Jan 2010

Evaluation Of Two Novel Aluminum-Free, Zinc-Based Glass Polyalkenoate Cements As Alternatives To Pmma Bone Cement For Use In Vertebroplasty And Balloon Kyphoplasty, Gladius Lewis, Mark R. Towler, Daniel Boyd, Matthew J. German, Anthony W. Wren, Owen M. Clarkin, Andrew Yates

Chemical and Biochemical Engineering Faculty Research & Creative Works

Vertebroplasty (VP) and balloon kyphoplasty (BKP) are now widely used for treating patients in whom the pain due to vertebral compression fractures is severe and has proved to be refractory to conservative treatment. These procedures involve percutaneous delivery of a bolus of an injectable bone cement either directly to the fractured vertebral body, VB (VP) or to a void created in it by an inflatable bone tamp (BKP). Thus, the cement is a vital component of both procedures. In the vast majority of VPs and BKPs, a poly(methyl methacrylate) (PMMA) bone cement is used. This material has many shortcomings, notably …

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