Emerging Frontiers in Surface Engineering of Biomaterials : Biocoatings and Surface Protection
Program Organizers: Kantesh Balani, Indian Institute of Technology Kanpur; Arvind Agarwal, Florida International University; Sandip Harimkar, Oklahoma State University; Winston Soboyejo, Princeton University
Tuesday 2:00 PM
October 18, 2011
Room: C226
Location: Greater Columbus Convention Center
Session Chair: Sandip Harimkar, Oklahoma State University; Kantesh Balani, Indian Institute of Technology Kanpur
2:00 PM
Polyvinyl Alcohol-HA Hydrogels Surface Modification through Octacalcium Phosphate by a Biomimetic Route: Avijit Guha1; Suprabha Nayar1; 1National Metallurgical Laboratory
Octacalcium phosphate (OCP) is a precursor phase formed during the in vivo mineralization of the biological tissue. This phase is easily converted into hydroxyapatite (HA), the main inorganic constituent of human bones and teeth. Simulated body fluid induced nucleation and growth of OCP on pre-formed polyvinyl alcohol-hydroxyapatite hydrogels has been observed and studied. Bulk structure of hydrogels governs their mechanical properties while surface chemistry largely controls the biological response. The surface modification is the key factor which influences the in vivo-interactions and the subsequent response. A good interfacing between hydrogel and the in vivo environment can only be achieved by a good compatibility between the two. Here we demonstrate that a uniform coating of crystalline OCP on the outer most layer of biomimetically synthesized PVA hydrogel is achieved by soaking the hydrogel in synthetic SBF at ambient temperature.
2:20 PM Student
Thermomechanical Properties of Polyimide-Based Block Copolymers Containing Ladder-like Polysilsequioxanes: Linqian Feng1; Jude Iorh1; 1the University of Cincinnati
A novel type of polyimide (PI)-polyurea (PU)-polysilsesquioxane (LPS) terpolymer was prepared by reacting ladder-like polysilsesquioxane (LPS), with polyurea and polyamide acid. The terpolymer thin film and coatings were obtained by solution casting onto a properly cleaned glass and aluminum alloy substrate, respectively, followed by thermal curing. The resulting terpolymer possessed outstanding thermomechanical properties and thermal stability. The LPS block composed of mercapto and fluoride side groups was synthesized by using the sol–gel and monomer self-organization methods. The presence of LPS containing fluoride and mercapto end groups improved the corrosion inhibition of aluminum alloy. In this paper the effect of composition and other processing variables on the thermomechanical and corrosion inhibition properties of specially designed polyimide based terpolymer coatings will be presented and compared with the constituent’s properties.
2:40 PM
Synthesis of Electrophoretic ZnO Coatings on Titanium: Shankar Chandra Prakash1; Abbas Ashik1; Parameswaran Prabhu1; R. Subramanian1; Ramaswamy Narayanan1; 1PSG College of Technology
ZnO is known to fight bacteria and its nanocrystalline form does not need external stimulus like ultra-violet radiation to cause the anti-microbial effect. Although it is widely studied and researched, ZnO production techniques are not cost-effective and hence newer synthesis methods have to be researched into. This work reports the synthesis of nano-crystalline ZnO produced by a cheap and efficient combustion method and electrophoretically depositing these powders on titanium. This involves the combustion of 12.5 mM zinc acetate at 500˚C using urea as fuel. The reaction is completed within 15 minutes. The fluffy combustion product obtained from the combustion reaction was crushed into powder and used for electrophoretic deposition. XRD confirmed the presence of nano crystalline ZnO and indicated the average crystal size to be in the range of 9-12 nm. Anti-bacterial studies are in progress to test the efficacy of the product’s antimicrobial activity.
3:00 PM Break
3:20 PM Cancelled
Coating a Large Variety of Surfaces by the Sonochemical Methods: Anti Bacterial, Anti Viral, Anti Biofilms and Antifungai Coatings on Textiles and Glasses: Aharon Gedanken1; 1Bar-Ilan University
In the current abstract I will detail our work using sonochemistry for coating textiles such as polyester, cotton, nylon, and nonwoven. In all cases a homogeneous coating of NPs was achieved. Silver is known for generations as antibacterial, and indeed the Ag NPs have killed the gram-negative E. Coli (strain 1313) as well as the gram-positive Staphylococus aureus (strain 195) bacteria very efficiently. Lately, since the FDA shows less enthusiasm towards Ag we have moved to NPs of ZnO, CuO and MgO as antibacterial agents. They were coated on the above-mentioned fabrics and showed excellent antibacterial properties.I will also report on the synthesis of nanosized fluorides materials and we demonstrate the bactericidal ability of these new fluoride nanomaterials to restrict bacterial colonization of two common biofilm pathogens. I will also the coating of antiviral NPs on textiles.
3:40 PM Concluding Comments