Surface analysis

Surface Plasmon Resonance (SPR)


  • Polymers or biomolecules, which adsorb at interfaces or which are bound via specific interactions or covalently. Layer thicknesses in the range of some tenths of nanometres up to several hundred nanometres



  • Reichert SR 7000 DC double channel instrument with flow system or cuvette


Evaluation methods and targets

  • Measurement of local change in refractive index at the sensor surface in real time
  • Relative change of the mass loading of a surface
  • If refractive index of adsorbed material is known: thickness of the adsorbed layer
  • Kinetics of adsorption / interaction


Application examples

  • Thickness determination of thin and ultra-thin polymer layers
  • Real-time monitoring of the build-up of a polymer layer
  • Determination of KD of an antibody/antigen interaction


Measuring principle


Comparative and additional methods

  • Ellipsometry
  • Atomic force microscopy