TDA Detector Array

The Viscotek TDA sets the standard for GPC/SEC technology and is the world’s leading multi-detector platform. As a Triple Detector Array it employs refractive index, viscometer and light scattering detectors all acting in concert, with each detector providing complimentary data on the macromolecules being analyzed.

In its Tetra Detector format, the addition of a UV detector provides a wealth of additional compositional data particularly when the optional Photodiode Array (PDA or DAD) is used to make spectral measurement of all wavelengths simultaneously.

In either format, it offers precise and accurate temperature control by housing all the detector cells and the chromatographic columns together in the same thermal chamber. This arrangement minimizes inter-detector volumes to reduce band broadening effects and ensures that detectors, connecting tubing and columns reside at the same temperature during the analysis. This provides unmatched baseline stability and data reproducibility, delivering reliable, robust results.

The TDA can be configured with any combination of the 4 detectors:

• Refractive Index for concentration
• Viscometer for size and structure
• Light Scattering for molecular weight
• UV for chemical composition

The detectors in the TDA are arranged in a unique series configuration with the viscometer after the RI which maximises the signals on all detectors.

In a single GPC/SEC experiment, the TDA provides:

• Absolute molecular weight without the assumptions, extrapolations or corrections required by alternative techniques.
• Molecular size expressed as Hydrodynamic Radius (Rh) to less than 1 nm and Radius of Gyration (Rg).
• Intrinsic viscosity or molecular density.
• Information on structure, conformation, aggregation and branching.

The TDA detectors:

	Light Scattering Detector The powerful light scattering detector in the TDA has two independent measuring points.  Low Angle (LALS) and Right Angle (RALS) to give easy measurement of absolute molecular weight of any size of molecule without corrections or extrapolation.
	Differential Viscometer Detector The 4-capillary differential viscometer provides a direct measurement of intrinsic viscosity and allows for the determination of molecular size, conformation and structure.
	Refractive Index Detector The high-sensitivity RI in the TDA has been designed specifically with multi-detection GPC/SEC in mind. It features a high power light source, wavelength matched with the light scattering, for maximum sensitivity and stability.
	UV/VIS or Photodiode Array Detector (PDA / DAD) The Viscotek TDA offers two UV options: a programmable UV/Vis detector or the unique Viscotek PDA, the first one ever integrated in a GPC/SEC system and software.

More information

	Featured presentations and application notes:
	Application communication: Protein and polymer molecular size by GPC/SEC The main goal of most Gel Permeation/Size Exclusion Chromatography (GPC/SEC) experiments is to determine the molecular weight distribution (MWD) of the sample or compare molecular weights (MW) of several samples.
	On-demand presentation: Protein characterization by triple detection Triple detection is used with size-exclusion chromatography to separate and characterize molecules such as proteins. Using triple detection allows the molecular weight and molecular size of a protein to be calculated independently of each other and retention time. This webinar will describe the technique and provide some example application data.
	More application notes and online presentations are available to search for FREE in the Malvern Application Library and Presentations Database (Requires Free registration).