SEC-SANS

SEC-SANS

D22 SEC-SANS can exist in two different configurations:

- one with only one column enabling to screen many Buffer D₂O contents

- one, more usual, with two columns enabling to equilibrate one column while eluting through the second one .

1. Buffer bottles
2. Buffer valves
3. Pumps
4. Mixing valve
5. Ante and Post 2-way valves
6. Injector
7. Column(s): HiTrap, Superdex75, Superdex200
8. Measurement cell
9. Spectrophotometer
10. Fraction Collector
11. Waste

The entire set up sits in a thermalised box and is controlled by Nomad through 3 tabs:

1. Samples Buffers tab to define your columns, buffers and samples with a title and their position
2. HPLC controller tab to set the chromatography parameters with up to 4 wavelength for absorbance measurement and the options to equilibrate the non-eluting column, to slow down the elution at a specific absorbance threshold to enable SANS data accumulation and to collect eluted fractions
3. Execution tab as for usual experiment.

Sample requirements: as for cuvette measurement, the minimum sample requirement is about 200uL at 1-2mg/mL (after dilution by the column). It obviously depends on the contrast. The exposure time is usually of the order of 20min (+ elution time). Each piece of equipment can also be controlled individually (the spectro for example).

All chromatography parameters and results are saved in the SANS nxs file.