SFG is a complex laser technique based on non-linear optics and has all the common advantages of laser spectrocopies; it is nondestructive, highly sensitive, and has good spatial, temporal, and spectral resolution. Infrared (IR) and visible sum-frequency generation spectroscopy is a powerful and versatile in situ surface probe that not only permits identification of surface molecular species, but also provides information about orientation of functional groups at the surface. This highly-sensitive method is suitable for interfaces between centrosymmetric crystalline solids, amorphous solids, and isotropic gasses or liquids under the electric dipole approximation. SFG is effective at the gas-solid, liquid-solid, liquid-gas, and liquid-liquid interface, and can be attempted on almost any system in which the surface or interface can be accessed by the light.

Surface chemistry controls numerous chemical and physiological properties of a polymer, including thromboresistance, biostability, lubricity, permeability, and abrasion resistance. Surface-modified polymers need to be well characterized in order to correlate these surface properties to the biofunctionality of the application. SFG validates that there is in fact a difference between the surface chemistry of surface-modified polymers and those that are not. In a recent study that appeared in the Journal of the American Chemical Society, PTG's BioSpan® segmented polyurethane modified with PDMS end groups (BioSpan® S) was analyzed using SFG. The results confirmed that the lower surface tension component effectively segregates to the surface in order to minimize the surface free energy of the system. Even at extremely low concentrations, the more hydrophobic silicone tail dominates the surface of BioSpan® S.

The Polymer Technology Group was founded in 1989 by Robert Ward, who is a recognized pioneer in the field of biomaterials and the company's CEO. PTG specializes in the research, development, scale-up, and manufacture of new polymers, medical devices, and components. PTG's commercial product portfolio includes two of the world's most extensively tested biomaterials in clinical use today, BioSpan® segmented polyurethane and Bionate® polycarbonate urethane. In addition, PTG offers Elasthane™ polyether urethane, as well as custom-fabricated components from our patented PurSil® silicone polyether urethane and CarboSil® silicone polycarbonate urethane. PTG's 32,000 square-foot facility houses the equipment and expertise to support production-scale polymer synthesis through contract medical device manufacturing.

CONTACT:
The Polymer Technology Group, Inc.
2810 7th Street
Berkeley, California 94710
Phone: 510-841-8800
Fax: 510-841-7800
http://www.polymertech.com
info@polymertech.com