The Nanodisc Membrane Scaffold Proteins (MSPs) market is stratified by protein type, each variant reflecting a distinct engineered amphipathic helical sequence that dictates disc diameter, stability, and lipid compatibility. MSP1, derived from the native apolipoprotein A‑I, forms discs of approximately 10 nm and is preferred for high‑resolution NMR studies due to its minimal curvature strain. MSP1D1 incorporates a truncation that reduces the scaffold length, yielding 8‑nm discs suited for cryo‑EM analyses of small membrane proteins. MSP1E3, with an extended helix bundle, produces larger 12‑nm nanodiscs, facilitating the incorporation of multi‑subunit complexes and enabling functional assays that require a broader lipid environment. MSP2 variants, engineered with additional cysteine residues, support site‑specific conjugation for immobilization or labeling applications, expanding utility in biosensor platforms. Collectively, these types account for the market’s breadth, with MSP1‑derived scaffolds representing roughly 55 % of sales, MSP1D1 and MSP1E3 together contributing 30 %, and MSP2‑based products comprising the remaining 15 %.