Amphipols are short amphipatic polymers that are specifically designed to stabilize membrane proteins in aqueous solutions.
Due to their dense distribution of hydrophobic chains they tightly bind to transmembrane surfaces of membrane proteins and cover it with a thin interfacial layer of surfactant. The resulting small hydrophilic complexes have several advantages over usually much larger protein detergent complexes, such as stability and functionality of the membrane protein.
Amphipol A8-35 is successfully applied as stabilizing agent in Cryo-EM[2-5] and X-ray crystallography.
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