WyattQELS™ On-Line Quasi Elastic Light Scattering from your HPLC
The WyattQELS (Quasi-Elastic-Light-Scattering) instrument contains a real time digital correlator. The correlator measures the autocorrelation function of the intensity signal from any one angle of the DAWN or from the 90 degree location of the miniDAWN. The correlator then calculates the hydrodynamic radius at each elution time in order to provide hydrodynamic radii over an entire chromatographic peak.
Unlike many other dynamic light scattering instruments, the WyattQELS detector, when interfaced to the DAWN, allows one to measure correlation as a function of angle. Particles larger than 150nm may scatter relatively little light at 90 degrees because of intra-particle interface or "Mie scattering".
This effect may cause significant distortion in computer particles size distribution for some kinds of polydisperse samples. Since the WyattQELS optical fiber can be moved easily to any one of the 18 DAWN angles, the measurements can be optimized for the best results for particles that are very large. With most other instruments, which only make measurements at 90 degrees, if large particles are present, the signals may be low or lost altogether. But with the WyattQELS you can always move the optical fiber to a lower or a higher angle.
WyattQELS Features include:
- Multiple Tau correlation design with a fixed range of channel from 480 nsec to ~1 hour (real-time).
- No sample time optimization required!
- A total of 264 channels with input data format of 5 bit for the first 16 channels, the the sample time doubles every 8 channels and the data width is incremented 1 bit for every set of channels. No pre-scaling required.
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For more immediate information, please download our application note.
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Download the WyattQELS brochure here. (642K)
BSA
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Polystyrene
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Lysozyme
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Click here to learn more about dynamic light scattering theory.
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Wyatt Technology is the world leader in providing the most advanced macromolecular and nanoparticle characterization tools. These instruments and software may be used to determine the absolute molecular weight and or size of macromolecules and nanoparticles and include: multi-angle light scattering, dynamic light scattering, high through-put dynamic light scattering, field flow fractionation, refractive index and viscometry detection.