Table 1. Comparison of various membrane mimetic and substitute technologies.

TOOL	ADVANTAGES/BENEFITS	DISADVANTAGES/CHALLENGES	EXAMPLES
LIPOSOMES	Closely mimics native membrane (fluidity, width, phase transitions) Mediates complex assembly Diffusion on surface is possible Encapsulate dyes, reagents, etc. Compartment forming (chemical gradients, assays, etc) Easily deposited onto a surface Simple to produce, size is controllable.	Instability - prone to burst or aggregate Heterogeneous (composition, protein binding, size) Not effective for solubilisation Difficult to freeze, requires thick ice and complicates high-resolution cryoEM reconstruction (strong incoherent signal) Large enough to scatter light Screening lipid compositions is low throughput	CryoEM (1–4) AFM (5,6) SCC (7) LM (8)
NANODISCS MSP1D1 cMSP26 NW50	Highly stable Can derive lipids native bilayers Smaller than liposomes (reducing ice thickness for cryoEM studies) Stabilisation of hydrophobic regions (like detergent) Mediates complex assembly Amenable to further purification Genetically encoded allowing customisation Click-chemistry compatible	Lipids in nanodiscs have altered properties compared to lipids in cell membranes Low surface area (diffusion dependent process) Production and purification are labour intensive Often requires extensive optimisation Poor efficiency of nanodisc formation, not effective for solubilisation Sizes are relatively limited	CryoEM (9–13)
DETERGENT	Simple and convenient means of solubilisation A broad selection with different chemistries Can induce spontaneous oligomerisation and/or pore formation Amenable to further purification	Do not provide a surface for assembly Detergent micelles are topologically different to native membranes Can introduce structural artefacts Protein stability is often an issue Lack protein/lipid interactions Empty micelles can interfere with cryoEM image processing	CryoEM (14–20)
AMPHIPOLS	Less likely to destabilise structure compared to detergent Stable, even when diluted Can be chemically modified or conjugated No interference with light-based experiments	Does not provide an assembly surface Not suitable at acidic pH or in excessive divalent ions. Cannot directly solubilise MPs Difficult to synthesis Polydisperse	CryoEM (21–24)
SMALPS	Detergent-free solubilisation of MPs. Maintain native lipids after solubilisation. Useful for lipidomics. Protein-lipids interactions are retained to a greater extent Compatible with further purification Highly stable once SMA disc forms Does not form micelles	Difficult to synthesise Polydisperse sizes Native bilayer properties are not preserved. Expensive Can affect protein purification	CryoEM (25) MS (26) SCC (27)
PEPTIDISC & SAPOSIN	Diameter of the disc is dependent on the protein diameter Works at low pH Genetically encoded Easy to produce in large quantities	No assembly surface Does not preserve bilayer properties
IN SITU	Direct observation of sample in native environment	Low resolution Low throughput Technically complex	CryoET (28,29) AFM (30,31) SCC (32)
SUPPORTED LIPID BILAYERS	Enables visualisation of diffusion dependent processes Large surface area Simple and readily applicable to AFM, SPR, TIRF, etc.	Lipid diffusion is significantly reduced compared to native bilayers Can easily study and visualise phase transition properties	AFM (5,6,33–35) LM (36–38)