BioSAXS

Contacts

Normand Cyr
Structural biology platform manager
normand.cyr@umontreal.ca

John Pascal
Professor
john.pascal@umontreal.ca

Link to the data analysis tutorial

Description of the equipment

Small Angle X-rays Scattering (SAXS)

Small angle X-rays scattering is a biophysical method for the analysis of biomolecules (proteins, RNA, DNA) in solution and provides information regarding to variations in the electronic density of molecular structures in solution. SAXS yields information on both size, shape, density and molecular weight of particles.

Description of the equipment

The SAXSLAB Bio-Nordic is equipped with a vacuum GANESHA platform which enables the measurement of X-rays scattering at small angles for vectors of momentum transfer (q-values) from 0.0006 to 3.4 Å-1, for both SAXS (small angle) and WAXS (wide angle) applications, for particles up to 150 nm in diameter.

X-rays source

The X-rays are generated by a Excillum MetalJet D2+ 70 kV source using a 95 % gallium alloy (liquid jet anode – 1.34 Å). This powerful X-rays source offer superior brightness when compared to a conventional rotating anode and thus enables fast analysis of samples.

Size-exclusion chromatography system

The optional addition of an ÄKTAmicro chromatography system (GE Healthcare) enables size-exclusion type separation of biomolecules prior to SAXS analysis. The inline attachment lets the research to simultaneously separate by chromatography and analyze by SAXS each detected peak. A UV light/detector (Biocube, SAXSLAB) is also present on the SAXS system for direct absorbance measurement.

Detector

The Bio-Nordic is equipped with a Dectris hybrid photon counting detector (Dectris EIGER2 R 1M) offering micrometric spacial resolution (75 µm x 75 µm) and a wide dynamic range and a large pixel array (1M pixels). The detector is water-cooled and installed in a vacuum chamber therefore eliminating air scattering.

High-throughput screening

A high-throughput robot installed on the Bio-Nordic enables screening refrigerated 96-well plates by automating liquid handling. Less than 20 µl is required per sample.

Softwares

  • Linux Ubuntu 16.04
  • RAW 1.4.2 (BioXolver version)
  • ATSAS 2.8.4
  • DENSS