Engineering Commons^™

Synthesis Of Regioselectively Acylated Quercetin Analogues With Improved Antiplatelet Activity, Yu Duan, Na Sun, Min Xue, Xiaolan Wang, Hu Yang

Chemical and Biochemical Engineering Faculty Research & Creative Works

The aim of the present study was to report on a complete synthetic approach, namely benzylation-hydrolysis-acylation-hydrogenation, to the synthesis of regioselectively acylated quercetin analogues using low-cost rutin as a starting material. Three quercetin analogues, quercetin-3-O-propionate (Q-pr), quercetin-3-O-butyrate (Q-bu) and quercetin-3-O-valerate (Q-va), containing 3-, 4- and 5-carbon aliphatic acyl chains, respectively, were synthesized and characterized with ¹H nuclear magnetic resonance (NMR), ¹³C NMR and mass spectrometry. Compared with quercetin, all three analogues exhibited improved lipophilicity. The lipophilicity of the analogue increased with increasing acyl chain length. Q-va exhibited the highest lipophilicity among the three analogues, but a lower water …

Titanium Addition Influences Antibacterial Activity Of Bioactive Glass Coatings On Metallic Implants, Omar Rodriguez, Wendy Stone, Emil H. Schemitsch, Paul Zalzal, Stephen Waldman, Marcello Papini, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

In an attempt to combat the possibility of bacterial infection and insufficient bone growth around metallic, surgical implants, bioactive glasses may be employed as coatings. In this work, silica-based and borate-based glass series were synthesized for this purpose and subsequently characterized in terms of antibacterial behavior, solubility and cytotoxicity. Borate-based glasses were found to exhibit significantly superior antibacterial properties and increased solubility compared to their silica-based counterparts, with BRT0 and BRT3 (borate-based glasses with 0 and 15 mol% of titanium dioxide incorporated, respectively) outperforming the remainder of the glasses, both borate and silicate based, in these respects. Atomic Absorption Spectroscopy …

Potency And Cytotoxicity Of A Novel Gallium-Containing Mesoporous Bioactive Glass/Chitosan Composite Scaffold As Hemostatic Agents, Sara Pourshahrestani, Ehsan Zeimaran, Nahrizul Adib Kadri, Nicola Gargiulo, Hassan Mahmood Jindal, Sangeetha Vasudevaraj Naveen, Shamala Devi Sekaran, Tunku Kamarul, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Chitosan-based hemostats are promising candidates for immediate hemorrhage control. However, they have some disadvantages and require further improvement to achieve the desired hemostatic efficiency. Here, a series of 1% Ga2O3-containing mesoporous bioactive glass-chitosan composite scaffolds (Ga-MBG/CHT) were constructed by the lyophilization process and the effect of various concentrations of Ga-MBG (10, 30, and 50 wt %) on the hemostatic function of the CHT scaffold was assessed as compared to that of Celox Rapid gauze (CXR), a current commercially available chitosan-coated hemostatic gauze. The prepared scaffolds exhibited >79% porosity and showed increased water uptake compared to that in CXR. The results …

Raman Spectral Variation For Human Fingernails Of Postmenopausal Women Is Dependent On Fracture Risk And Osteoporosis Status, J. R. Beattie, M. C. Caraher, N. M. Cummins, O. M. O'Driscoll, R. Eastell, S. H. Ralston, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Patients diagnosed with osteoporosis have reported loss of fingernail resilience as the disease progresses. Keratin is the predominant protein in human nail tissue, and its structure has been postulated to be different in fingernails clipped from subjects who have sustained fragility fractures and those who have not, which may offer a window into the donor's bone health. This study was designed to qualify these differences, which may lead to the development of a novel screening tool for fracture risk. Raman spectroscopy was used to measure the fingernails of 633 postmenopausal women who presented at six fracture clinics located across the …

Common Treatments And Procedures Used For Fractures Of The Distal Radius And Scaphoid: A Review, Basel A. Khader, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

The distal radius and the scaphoid are the most commonly injured carpal bones among both active adults and the osteoporotic elderly. The purpose of surgical treatment is to restore form and function to the wrist. Depending on the nature of the fracture, either topical procedures or invasive surgery can be applied. This article critiques the treatments currently used for fixation of wrist fractures in order to drive the development of new materials to improve patient outcomes.

Polysaccharide Fabrication Platforms And Biocompatibility Assessment As Candidate Wound Dressing Materials, Donald C. Aduba Jr., Hu Yang

Chemical and Biochemical Engineering Faculty Research & Creative Works

Wound dressings are critical for wound care because they provide a physical barrier between the injury site and outside environment, preventing further damage or infection. Wound dressings also manage and even encourage the wound healing process for proper recovery. Polysaccharide biopolymers are slowly becoming popular as modern wound dressings materials because they are naturally derived, highly abundant, inexpensive, absorbent, non-toxic and non-immunogenic. Polysaccharide biopolymers have also been processed into biomimetic platforms that offer a bioactive component in wound dressings that aid the healing process. This review primarily focuses on the fabrication and biocompatibility assessment of polysaccharide materials. Specifically, fabrication platforms …

A Novel Tantalum-Containing Bioglass. Part I. Structure And Solubility, Adel Mf Alhalawani, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Bio glasses are employed for surgical augmentation in a range of hard tissue applications. Tantalum is a bioactive and biocompatible transition metal that has been used as an orthopedic medical device. It has a range of biological and physical properties that make its incorporation into ionic form into bioactive glass systems promising for various clinical applications. The work herein reports the characterization and properties of novel tantalum-containing glasses. A series of glasses based on the system 48SiO₂-(36-X)ZnO-6CaO-8SrO-2P₂O₅-XTa₂O₅ with X varying from 0 mol% (TA0) to 0.5 mol% (TA2) were synthesized. The …

Characterization And Fracture Property Of Different Strontium-Containing Borate-Based Glass Coatings For Ti6al4v Substrates, Yiming Li, Ali Matinmanesh, Declan J. Curran, Emil H. Schemitsch, Paul Zalzal, Marcello Papini, Anthony W. Wren, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

This work considered the effect of increasing Strontium ion (Sr²⁺) content on the structure of a series of glasses based on the B₂O₃-P₂O₅-CaCO₃-Na₂CO₃-TiO₂-SrCO₃ series and their resultant fracture toughness when coated onto a surgical metal substrate. Six glasses with increasing Sr²⁺ content (0 to 25 mol%) were synthesized and subsequently characterized by X-ray Diffraction (XRD), Differential Thermal Analysis (DTA) and both Magic Angle Spinning Nuclear Magnetic Resonance (MAS-NMR) and Raman Spectroscopy. These techniques confirmed that increased Sr²⁺ content induced …

A Novel Tantalum-Containing Bioglass. Part Ii. Development Of A Bioadhesive For Sternal Fixation And Repair, Adel Mf Alhalawani, Cina Mehrvar, Wendy Stone, Stephen D. Waldman, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

With over a million median sternotomy surgeries performed worldwide every year, sternal wound complications have posed a serious risk to the affected patients. A rigid therapeutic sternal fixation device has therefore become a necessity. In this work, the incorporation of up to 0.5 mol% of tantalum pentoxide (Ta₂O₅), in exchange for zinc oxide (ZnO), into the SiO₂-ZnO-CaO-SrO-P₂O₅ glass system is presented. The effect of Ta incorporation on the physical, chemical and biological properties of the glass polyalkenoate cements (GPCs) prepared from them have been presented in this manuscript. The data obtained …

3d Bioprinting A Pcl/13-93b3 Glass Composite And Its Potential Use As A Bio-Ink, Caroline Blair Murphy

Masters Theses

"A major limitation of using synthetic scaffolds in tissue engineering is little growth of incorporated cells in the interior of the scaffold, resulting in insufficient angiogenesis in the scaffold interior. Recently, cells have been 3D bioprinted concurrently with biomaterials to produce a cellularized, bioactive, angiogenic 3D environment. This thesis describes a novel solvent-extrusion method for printing polycaprolactone (PCL)/bioactive borate glass composite as a biomaterial for a cell-laden scaffold.

Bioactive borate glass was added to a mixture of PCL and organic solvent to make an extrudable paste, creating scaffolds measuring 10×10×1 mm³ in overall dimensions with pore sizes ranging from …

The Viability Of Advantg Deterministic Method For Synthetic Radiography Generation, Andrew Albert Bingham

Masters Theses

"Time sensitive and high resolution image simulations are needed for synthetic radiography generation. The standard stochastic approach requires lengthy run times with poor statistics at higher resolutions. The investigation of the viability of a deterministic approach to synthetic radiography image generation was explored. The aim was to analyze a computational time decrease over the stochastic method. ADVANTG was compared to MCNP in multiple scenarios including a Benchtop CT prototype, to simulate high resolution radiography images. By using ADVANTG deterministic code to simulate radiography images the computational time was found to decrease over 10 times compared to the MCNP stochastic approach"--Abstract, …

Combination Of Bmp-2 And Relaxin To Induce Osteogenesis In Vivo, Sahitya Injamuri

Masters Theses

"Bone grafts are a common procedure for treating craniofacial injuries such as trauma, surgery, and reconstruction. Autografts and allografts have limitations which encourages the use of synthetic bone grafts. While synthetic bone grafts, such as hydroxyapatite (HA) microspheres, are advantageous for their cost and reproducibility, they lack the cells and growth factors needed for proper osteoinduction. Bone morphogenetic protein-2 (BMP-2) has been shown to increase the osteoinduction of grafts but the effective dose is above physiological levels and causes undesired effects on the body. Relaxin has been shown to enhance BMP-2's ability to induce bone formation in vitro and thus …