SurFACTSin Biomaterials Summer 2013 | Volume 18 Issue 3 2013 President’s Message: Inside this Issue Dear Fellow Biomaterial Surface discussing cutting edge technologies Pg. 2: Altering Biological Aficionados, and recent scientific developments. Interfaces with Gas Plasma: In addition, this event includes the Example Applications You are invited to join me, your popular and the highly anticipated colleagues, academic and industry Point-Counterpoint Debate session, By Khoren Sahagian, Mikki leaders and invited distinguished Student Poster Competition, and Larner, and Stephen L. scientists in beautiful Minneapolis, Excellence in Surface Science Awardee Minnesota for The Surfaces in address. For a full list of session topics Kaplan. Plasma Technology By Briana N. Vogen, Laurie R. Lawin, Leandro Forciniti, Daniel E. Guire, Biomaterials Foundation’s Annual please visit www.surfaces.org. Systems, Belmont, CA and Tahmina Naqvi; Innovative Surface Technologies, Inc. (ISurTec®), BioInterface Conference on October 7-9, 2013 at the Hotel Sofitel. This Registration is now open and we annual meeting provides an intimate encourage you and your colleagues to Pg. 6: Ex-situ Lift-out and opportunity to meet and network with register early to guarantee your spot at EXpressLO™ for Site Specific other professionals while discussing this conference but to also save money new developments in the biomaterials with the SIBF early registration rate. Surface Analysis industry. Register today at www.surfaces.org. By Lucille A. Giannuzzi The Foundation’s mission is to explore On behalf of the Program Committee, L.A. Giannuzzi & Associates the creative solutions to technical Foundation’s members and Board LLC challenges at the BioInterface of Directors, I hope you will join us by fostering education and at BioInterface in October for an multidisciplinary cooperation among enjoyable and valuable experience that pg. 8: Regulatory Update industrial, academic, clinical, and will increase your scientific education, By Phil Triolo regulatory communities. professional development, and further the research you are conducting. Thanks to the efforts of the Program Pg. 9: Calendar of Events Committee we have a truly remarkable Sincerely, program. The program consists of Peter Edelman scientific sessions featuring well- President, Surfaces in Biomaterials Pg. 10: Membership Information known presenters and invited speakers Foundation Members are encouraged to submit articles for future editions of SurFACTS. Please e-mail your report (with all appropriate figures and graphics) to Staff Editor Jazzy McCroskey at [email protected] for consideration in a future issue. Deadlines for upcoming issues are posted on surfaces.org. SurFACTS in Biomaterials is the official Altering Biological Interfaces with Gas Plasma: publication of the foundation and is dedicated to serving industrial engineers, research scientists, and academicians working in the field of biomateri- Example Applications als, biomedical devices, or diagnostic research. Foundation Officers By Khoren Sahagian, Mikki Larner, and Stephen L. Kaplan. Plasma Technology Systems, Peter Edelman, President Boston Scientific Belmont, CA 3 Scimed Place Maple Grove, MN 55311 Telephone (763) 255-0282 Lawrence Salvati, President-Elect Bausch & Lomb Controlled Surfaces with Enhanced 1400 North Goodman Street Surface interactions play a critical PO Box 30450 Binding Rochester, NY 14609-0450 role in biological and polymeric Aylvin Dias, Vice President DSM Biomedical systems. Reactive gas plasma allows Koestraat 1,PO Box 18 Active microfluidic devices, sensors 6160 MD Geleen customization of surface chemistry The Netherlands and implantable devices often require Telephone + 31 46 4760330 without significantly affecting the Savannah Gore, Secretary a specific binding property or binding W.L. Gore & Associates bulk. In their energized state, the 3250 West Kiltie Lane capacity in order to change reactions Flagstaff, AZ 86001 molecular fragments in a gas plasma Telephone (928) 864-4383 with an environment or biological Mark Smith, Treasurer will effectively restructure the topmost American Preclinical Services fluid The most common systems 8945 Evergreen Blvd. layer in a single controlled operation. Minneapolis, MN 55433 utilize specific functional groups such Telephone (763) 486-5769 Dan Hook, Past President as amine, hydroxyl, or carboxyl for Bausch & Lomb The exact chemical formulation of 1400 North Goodman Street conjugation to protein, molecule, PO Box 30450 gas plasma may vary from simple to Rochester, NY 14609-0450 complex and there is rarely a single integrin, or adhesive component. Telephone (585) 338-6580 route to achieve a desired surface Gas plasma begins by removing Committee Chairs functionality. Ultimately there are Membership organic surface contaminants by Robert Kellar and Jeannette Polkinghorne three primary variables that govern Program reducing them to volatile compounds. Joe Chinn the resulting surface modification: Academic Member Representative plasma chemistry, energy per mol, The nascent surface is subsequently Kristen O’Halloran Cardinal reacted to process specific plasma and cycle time. Judicious selection Foundation Office Staff chemistry. of these process conditions will yield Scott E. Franzmeier, Executive Director 1000 Westgate Drive, Suite 252 high quality surface treatment of both St. Paul, MN 55114 The intensity and duration of a Telephone 651-290-6278 organic and inorganic substrates. tEmail: [email protected] plasma process impacts the resulting surface functionality and density. If A low pressure plasma reactor is SurFACTS in Biomaterials Editors the density of a functional moiety is a complete chemistry toolbox for Executive Editor either too high or too low this may Joe McGonigle altering biological interfaces. SurModics, Inc. hinder an intended surface reactivity. [email protected] Staff Editor Table 1 illustrates the percentage of Jazzy McCroskey Ewald Consulting elemental nitrogen detected on a gold [email protected] surface as measured by XPS before Intellectual Property and Legal Editor Colin Fairman, JD, Ph. D. and after plasma functionalization1. Fulbright & Jaworski This amine is covalently bound to the [email protected] Biomaterials Editor surface meaning it is permanently Melissa Reynolds, Ph. D. Colorado State University incorporated onto the surface. This is [email protected] exemplified by the persisting nitrogen Surface Characterization and Analysis Editor Bill Theilacker composition post solvent wash. Medtronic Figure 1 demonstrates different amine [email protected] Regulatory Editor densities resulting from varying plasma Phil Triolo Phil Triolo & Associates LC process intensity and exposure. It is [email protected] noteworthy that plasma processing Advertising Manager Ewald Consulting is rarely a linear phenomenon. [email protected] Additional power or time may not © 2012 published by the translate into denser species loading. Surfaces in Biomaterials Foundation. All rights reserved. 2 appears to reach its maximum relative composition at a power of 50 Watts (W). A minimum in C:S ratio of 3.3 is found at 50 W and increases with power suggesting that higher plasma power lead to extensive fragmentation of the carbon-sulfur bond in mercaptopropyltrimethoxysilane. Table 1 XPS measurement of amine incorporation onto a gold surface. The modification is permanently bound to the surface and persists after a solvent wash Figure 2. Impact of power on sulfur species incorporation on glass nano-pipetter Figure 1 The relative amine density on a surface as related to process power and duration of a plasma surface modification Figures 2 and 3 illustrate impact of variation in elemental composition to plasma power and precursor concentration for a quartz nano-pipette. The nano-pipette is a device used for electrical detection of DNA-functionalized nanoparticles2,3. Figure 3 Sulfur content as a percentage of time and The ability to tailor surface properties of such concentration nano-scale devices are essential to avoid undesired adsorption of biological material onto the walls of a Bioactive Surfaces nano channel since it can alter flow properties as well as electrical properties of the channel. Dynamic interactions exist between surfaces and living organisms. Biocompatibility is loosely achieved Plasma-enhanced chemical vapor deposition (PECVD) if a device functions without eliciting an unfavorable of mercaptopropyltrimethoxysilane was investigated response in a living system. Surface energy, ionic as an alternative method to silanize the internal interaction, and intermolecular forces all play a role surfaces of these nano-pipettes. The mercaptosilane in the adsorption of proteins. A host’s immune in a subsequent step was coupled to bovine SA. system may respond to implantable devices by marking the surface with communicative molecules. An interesting feature is observed. Sulfur content Immunological response may be suppressed by 3 altering surface chemistry. S. Kane et al. demonstrates for performance as flexible gas and/or liquid the feasibility of plasma polymerized polyethylene barriers5. Figure 5 demonstrates plasma processes glycol (PEG)-like hydrogels on the surfaces of which reduce static friction as deposited on a implantable ultra high molecular weight polyethylene fluoroelastomer surface. Plasma treated components (UHMWPE)4. Figure 4 compares the protein were then soaked in oil for 48 hours and the change in adsorption via optical