Viscotek, a Malvern
company, has published new application notes illustrating the extended capabilities
of gel permeation chromatography/size exclusion chromatography (GPC/SEC) using
the newphotodiode array (PDA) detector for the TDAMax™ system. Now available
on the Viscotek website, these application notes illustrate how the new detection
technology brings greater flexibility to multi-component characterization and
analysis in fields from polymer science to biopharmaceuticals. The application
notes describe 'Conjugated polymer analysis by GPC-PDA' and 'Polymer blend analysis
by GPC-PDA' respectively. Both are freely downloadable at http://www.viscotek.com/gpcpda.htm
The Viscotek TDAmax is a comprehensive GPC/SEC system with an integrated triple
or tetra detector array. By capturing absorption spectra across the UV-vis wavelength
range, the new PDA detector provides a fingerprint of each 'time slice'
of the sample as it elutes from the column. Measurement times are just 30 to
40 minutes, making the system highly productive.
UV detection is used routinely to identify protein and polymer species as they
elute, and can differentiate between components when other detection methods
cannot. However, a conventional system measures at a single wavelength. In contrast,
the new PDA detector captures data across the range 190 to 500 nm, allowing
users to select wavelengths of interest after the analysis has been carried
The PDA also has particular application in the field of smart material research,
since unique electrical, thermal or photochromic properties often correlate
directly with UV absorption characteristics. The information it gives can be
used in both product and process development.
The UV cell of the PDA sits in the temperature controlled zone of the TDAMax™,
operating at up to 80oC. Viscotek's powerful OmniSEC™ software package
allows data to be displayed as information-rich 3-D images that simplify interpretation.
Gel Permeation Chromatography (GPC), also known as Size Exclusion Chromatography
(SEC), is a chromatographic technique that employs specialized columns to separate
natural and synthetic polymers, biopolymers and nanoparticles on the basis of
size. When GPC/SEC is coupled with advanced detectors a range of additional
parameters can be determined, including intrinsic viscosity, molecular size,
and long chain branching.