Surface Plasmon Resonance (SPR) is a powerful label-free technique to measure biomolecular interactions in real-time. There is a broad range of applications where SENSIA’s Indicator comes into play, wherever the study of biomolecular interactions is important: chemical and biochemical sensing, drug discovery, diagnostics, proteomics, genomics, forensics, food analysis, environmental monitoring…
A SPR (Surface Plasmon Resonance) sensor based in the Kretschmann configuration is used in this instrument to achieve the resonant condition by total internal reflection. A polarised divergent laser diode light strikes into two flow cells, with a volume of 180nl. A prism and multi-photodiodes are located on concentric rotary stages.
The Indicator system shows a detection limit of approx. 500 attomolar in the DNA detection with the combined use of graphene biosensors and gold nanoparticles..
The sensor consists of the prism itself, that has been nanometallised with optimal Ti and Au nanolayers. Self assembled monolayers or thin films add the surface chemistry functionality required for the sensor surface to detect a binding partner.
Monitoring changes in refractive index as a function of time allows real-time analysis of the binding events occurring at the sensor surface due to the continuous flow of buffers and samples provided by the flow injection system.
Several biomolecular interactions have been explored in SPR sensors as, for example, antibody-antigen, receptor-ligand or hormone-receptor because a wide variety of affinity ligands can be used: antibodies, antibody fragments, genetically engineered antibody derivatives, lectins, membrane receptors, nucleic acids, gene fusion protein, hormones, viruses, bacteria,…