Localized SPR


LSPR instruments utilize a broad band white light source such as an LED to illuminate the nanoparticle sensor substrate. A spectrometer serves as the detector and can be placed in either a transmission or reflection arrangement. The spectrometer provides a reading of the absorbance spectrum of the sensor substrate. The nanoparticle substrates have a characteristic absorbance peak in the visible spectrum due to the LSPR effect. The properties of this absorbance peak (spectral position, absorbance height) are dependent on the local optical properties surrounding the nanoparticles. When a molecule binds to the surface of the nanoparticle, it changes the local optical properties and causes the absorbance peak to change. The properties of the absorbance peak can be monitoring in real-time, providing time resolved molecular analysis on the nanoscale. The size, shape, and material of the nanoparticles can be tuned in order to maximize sensor performance for specific applications.

LSPR principle
LSPR principle


LSPR AG’s technology offers high-throughput, label-free detection by industrializing Localized Surface Plasmon Resonance (LSPR) spectroscopy into a sensitive, versatile and powerful sensor for biomolecular quantification and probing of biological interaction at nanoscale without need for expensive proprietary instruments. By utilizing the field enhancements in arrays of metallic nanostructures, LSPR AG’s biosensors enable label-free analysis that can be completed in less than an hour (for 96 samples) with an industry standard microplate reader present in the majority of biochemical laboratories.
Therefore LSPR AG’s platform constituted of:

  1. SBS compliant biosensors,
  2. Intuitive front end software, simplifies the assay build up dramatically and further decreases cost and complexity significantly.

In a typical quantitation assay, sample solutions are pipetted into the wells of the LSPR Biosensor coated with detection molecules for immobilization. Concentrations of unknown samples are determined by means of extrapolation from a calibration curve based on known antibody/protein concentrations. The dedicated software PLASMON for data collection and post-processing works with most commercial microplate readers. As the analyte-to-ligand binding is measured directly and no additional reagents are needed, it renders the method easy to use and yields presentable results in a short time. Moreover, due to the strong local field enhancements of the nanostructured sensor surface it is much less susceptible to bulk effects and measurements in complex media are more straightforward.

LSPR sensor
LSPR sensors