Small-angle X-ray scattering at MPI Göttingen:
Hilgenberg implements a flow system for protein measurement

The small-angle X-ray scattering method enables finest structures to be determined, e.g. of proteins or liquid crystals. Whenever the workgroup “Structural dynamics of biochemical systems” at the Max Planck Institute for Biophysical Chemistry in Göttingen applies this process, Hilgenberg's capillaries are also involved.

More precisely: The small-angle X-ray scattering method – which has been applied by the researchers in Göttingen since 2003 – determines the spacing between lattice planes. Hereby, X-rays are deflected or scattered by the electrons of the atoms in the lattice. In accordance with Bragg's Law, the deflection angle enables the spacing between the planes to be determined.

 

The magnitudes of these spaces lie in a range between 0,1 and 10 nm. To obtain a measurable scattering angle, the wavelength of the radiation source used must be of the same magnitude as that of the spacing between the planes. For this reason, X-rays are required, which have wavelengths in the range between 0,001 nm and about 10 nm.

 

For the measurement, the samples are filled into Hilgenberg capillaries of borosilicate glass with an outer diameter of 1 mm, which are subsequently sealed vacuum-tight. The sealed capillaries are inserted into a special sample holder that is then placed in the temperature-controlled unit of the measuring equipment.

 

Subsequently, a Kratky camera diverts an X-ray beam with a width of about 50 μm from a copper Xray source onto the test tube. Finally, the scattered radiation is measured by means of a detector located about 1 m away from the sample. To prevent the detector being damaged, a so-called primary beam stop is fitted in the vacuum chamber, which blocks some 90% of the diverted primary X-ray beam.

 

Because the demand for protein measurements has increased greatly, the researchers in Göttingen decided to use a capillary flow system in 2012. In order to implement this system, Hilgenberg technicians fitted the extremely filigree test tube firmly into the sample holder by hand. Subsequently, the necessary fine tubes were glued to the ends of the capillaries on-site in Göttingen.

 

Apart from an improved work sequence, the flow system installed in cooperation with Hilgenberg also permits re-use of the samples after the measurement.

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  • Glass tube with side-opening
  • Glass fibers with sphere formed end
  • NMR Tubes with thread for low vacuum applications
  • Mark tubes with special inner surface
  • Mini test tubes with extended flange
  • New preform for redrawing of capillaries
  • Test tubes with sagging at the bottom
  • Cloning cylinders with numbering
  • Large-volume theta cross-section capillaries
  • High tightness with new standard cap
  • Complex component made of quartz glass
  • Dropper pipettes in many sizes and designs
  • Packing glasses protected from light
  • Ampoules with built-in test leckage
  • Thick-walled sample vessels
  • Measuring ampoules with conical bottom
  • Special glass capillaries for measurements
  • Glass capillaries with constriction
  • Finely scaled glass cannulas
  • CNC processing of glass plates
  • New 5 mm NMR standard caps
  • Glass crucible for thermal analyses
  • Glass capillaries with graduation
  • Square capillary with 9 internal channels
  • 9-fold capillary made of borosilicate glass 3.3
  • Our tool for cutting glass capillaries
  • Diamond wire for cutting capillaries
  • Sight glasses (laser structured)
  • Very thick-walled capillaries
  • Polyimide coated filling needles
  • Ampoules with small volume
  • NMR tubes colored (UV protection)
  • NMR septum caps (increased denseness)
  • NMR tubes (barcode & constriction)
  • Mark tubes with perforated bottom
  • Test tubes with hole e.g. as vent
  • Test tubes with grooved rim
  • Oval capillaires (thin-walled)
  • Triangular capillaries (thin-walled)
  • Twisted capillaries by hot forming
  • Multi-channel capillaries (circular array)
  • Special light pipe made of glass
  • Luggin-capillary for measurements
  • Test mandrels (different materials)
  • Carpoules with special-rolled rim
  • Glass capillary for the stimulation
  • XRD-capillary with Luer-connector
  • Glass nozzle with seal-and retaining ring
  • Glass capillary with side-mounted connectors
  • Easily destructible glass ampoules
  • Glass rods with surface patterning
  • Long-conical focusing nozzles
  • Surface patterning of glass substrates
  • Laser sublimation-drilling in flat capillaries
  • Thin needles up to 180 ° flexible
  • Glass needles with curved tip
  • Polished to precision glass rings
  • Glass rods with partially-frosted surface
  • Sealing glass with high thermal expansion