Released on: April 9, 2008, 7:44 am

Press Release Author: The Scott Partnership

Industry: Pharmaceuticals

Press Release Summary:
SANTA BARBARA, CALIFORNIA (April 9 2008) - Wyatt Technology, the world
leader in absolute macromolecular characterization instruments, has
published a new, free-of-charge application note to demonstrate the accurate
and reliable characterization of polyurethanes used in medical applications.
Wyatt\'s powerful Multi-Angle Light Scattering (MALS) detectors were found to
provide vital information about the molecular structure of polyurethanes
when coupled to the company\'s innovative on-line ViscoStar viscometer.

Press Release Body: NEW APPLICATION NOTE FROM WYATT DEMONSTRATES THE ACCURATE AND
RELIABLE CHARACTERIZATION OF POLYURETHANES IN MEDICAL DEVICES

SANTA BARBARA, CALIFORNIA (April 9 2008) - Wyatt Technology, the world
leader in absolute macromolecular characterization instruments, has
published a new, free-of-charge application note to demonstrate the accurate
and reliable characterization of polyurethanes used in medical applications.
Wyatt\'s powerful Multi-Angle Light Scattering (MALS) detectors were found to
provide vital information about the molecular structure of polyurethanes
when coupled to the company\'s innovative on-line ViscoStar viscometer.

Polyurethanes are increasingly being used in medical applications,
outperforming many other materials with regards to robustness,
biocompatibility, hemocompatibility, flexibility, abrasion resistance and
processing versatility. Silicone, for example, is difficult to extrude and
does not bond easily to non-silicone components. PVC is associated with
increased concerns regarding leachable plasticizers while becoming brittle
at low temperatures. Applications include short-term implants, artificial
hearts, catheter and general-purpose tubing, surgical drains, intra-aortic
balloon pumps, dialysis devices and medical garments. It is of utmost
importance to test the structure-property relationships of polyurethanes
prior to production in order to ensure that factors such as chemical
composition, molar mass and molecular structure are within specifications to
avoid possible fatal consequences to the device users.

Valuable information about the polymer structure and polymer-solvent
interactions can be obtained from the log-log relation between the intrinsic
viscosity and molar mass, called a Mark-Houwink plot. The typical way to
determine a Mark-Houwink plot involves preparing narrow fractions and their
characterization with batch light scattering and a capillary viscometer.
However, this procedure is laborious and unsuitable for routine work. An
efficient and rapid way to generate Mark-Houwink plots is to couple a MALS
detector to an on-line viscometer and Size Exclusion Chromatograph. Such a
configuration can achieve excellent repeatability and accuracy for sensitive
comparison of slightly different samples.

For this particular application, Wyatt\'s SEC-MALS instrument and ViscoStar
viscometer were combined to measure the Mark Houwink parameters of two
polyurethanes. The curvature of the two Mark Houwink plots indicated
branching in both polymers. In addition, the plots overlapped in the region
of lower molar masses, indicating an identical degree of branching.
Deviation of the plots towards higher molar masses revealed a higher
branching degree of the red polymer, the plot of which became flat at the
region of higher molar masses. This fact was explained by the presence of
compact sphere-like fractions, which may be important for the final
properties of the material.

For more information on Wyatt Technology\'s SEC-MALS instruments and the
ViscoStar viscometer or to obtain a copy of this application note, please
visit www.wyatt.com or e-mail info@wyatt.com

###

About Wyatt
Based in Santa Barbara, California, Wyatt Technology is the world\'s leading
provider of instruments for absolute macromolecular characterization. With
over 35 years\' experience developing multi-angle light scattering detectors,
working with customers in the biotechnology, chemical, petrochemical,
pharmaceutical, academic and government arenas, Wyatt prides itself on its
entrepreneurial spirit, and the uniqueness of its offerings. The Company\'s
groundbreaking technology and uncompromising levels of customer care make
Wyatt the global hallmark in its field. For more information, please visit
www.wyatt.com

For further press information please contact: Laura Browne, The Scott
Partnership, 1 Whiteside, Station Road, Holmes Chapel, Cheshire. CW4 8AA
United Kingdom Tel: + 44 1477 539539 Fax: +44 1477 539540 mail to:
wyatt@scottpr.com


Web Site: http://www.wyatt.com

Contact Details: For further press information please contact: Laura Browne, The Scott
Partnership, 1 Whiteside, Station Road, Holmes Chapel, Cheshire. CW4 8AA
United Kingdom Tel: + 44 1477 539539 Fax: +44 1477 539540 mail to:
wyatt@scottpr.com