Biomembrane
SPR can help you measure the dynamics of biofilm interactions and potential structural changes.
In addition to acting as a barrier, cell membrane and mitochondrial membrane play important biochemical and biophysical roles. In addition, as the microenvironment of synthesis and catalytic reaction, cell membrane also contains all cell signal components. In drug development, nanoparticle biological interaction, targeted drug delivery, gene therapy and personalized drugs, the interaction between molecules and biofilms has been studied.
The applications of SPR in biofilm include:
1. Defect research of lipid membrane expansion
2. The formation of lipid membrane on various substrates
3. Biofilm quality assessment
4. Combination of SPR and electrochemistry to study the electrical properties of biofilm
5. From biofilm measurement to living cell measurement
Five key questions that SPR can answer in Biophysics:
1. What is the kinetics of supporting lipid bilayers?
2. How does nanoparticle x interact with a biomembrane?
3. How do membrane proteins (such as GPCR) interact with drugs?
4. What is the quality (thickness and optical density) of the biomembrane?
5. How stable is the membrane system in the air?
Application notes of lipid layer properties supported by SPR
Lipid membrane can simulate biological barrier in vitro, such as cell membrane. It is also possible to combine other molecules, such as receptors or membrane proteins, into the lipid layer structure to mimic the specific functions of biofilms. Because of these properties, the lipid layer structure can be widely used in biochemistry and drug research. SPR was used to characterize lipid layer structures adsorbed on a different substrates. Silicon dioxide and low molecule weight dextran surfaces supported formation of lipid bilayer (SLB) whereas thiolated polyethylene glycol supported vesicular layer formation (SLV). Thickness and refractive index of deposited lipid layer was calculated: SLB was about 5nm thick layer whereas SLV was 10nm thick layer.
Drug interactions with monolayer cells
In vitro cell detection is widely used in drug development. Generally speaking, the materials that need to be labeled are based on UV, fluorescence or mass spectrometry. SPR can measure the interaction in real-time without labeling. The monolayer of Madin-Darby canine kidney (MDCKII) cells deposited on the gold sensor slide. The interaction of propranolol and D-mannitol with the cell monolayer was successfully determined. After stimulation, some propranolol remained in the cell layer, while D-mannitol was removed. Through the measurement of SPR, It was possible to distinguish between paracellular and transcellular drug absorption routes.
