DAWN HELEOS II MALS (Multi Angle Light Scattering)

Location - Britannia 107

For enquiries, please contact - Dr. Karin Smorodinsky-Atias

The information provided in this section is taken from the “Hardware Manual for the DAWN HELEOS Light Scattering Instrument” and "Optilab rEX User’s Guide" by Waters Corporation (Wyatt Technology).

Instrument details

The DAWN HELEOS II light scattering detector and the Optilab rEX differential Refractive Index (dRI) detector were acquired in 2009 from Wyatt Technology.

This system measures scattered light at 18 different angles simultaneously and can determine the molar masses of polymers and biopolymers from a thousand to hundreds of millions of daltons.

Each photodetector has its own DSP (Digital Signal Processor) chip for processing the analog signal.

The DAWN HELEOS II uses a 120 mW GaAs linearly polarized laser operating at 658 nm, which after intensity stabilization delivers 100 mW to the sample.

The system is also equipped with an integrated COMET™ device for ultrasonic cell cleaning, and a built-in forward laser monitor to maintain constant laser output over time.

The Optilab rEX has a linear array of 512 photodiodes and a new flow cell design that allows the measurement of a fluid’s absolute Refractive Index (aRI) in addition to the dRI between two fluids.