What techniques can be used to measure the interactions between membrane proteins and lipids?

The two main techniques that can be used to measure the interactions between membrane proteins and lipids are Fluorescence Spectroscopy and Electron Spin Resonance. 

Fluorescence Spectroscopy measures the changes in fluorescence intensity, which indicates how strongly or weakly membrane proteins interact with specific lipids around them. Fluorescence spectroscopy offers several advantages over other techniques including high spatial resolution at hundreds of nanometers level, exceptional sensitivity at single-molecule level, and outstanding flexibility. 

Electron Spin Resonance (ESR), also known as Electron Paramagnetic Resonance (EPR), relies on the absorption of microwave radiation by paramagnetic materials that contain unpaired electrons when exposed to a robust magnetic field. It involves holding the sample in a very strong magnetic field while applying electromagnetic radiation monochromatically. The non-destructive nature of ESR makes it a preferred technique to measure the interactions between membrane proteins and lipids in transition metal complexes and crystal geometries.