Hybrid Double-Chain Maltose-Based Detergents: Synthesis and Colloidal and Biochemical Evaluation

Four hybrid double-chain surfactants with a maltose polar head were synthesized. The apolar domain consists of a hydrogenated chain, and a partially fluorinated chain made of a propyl hydrogenated spacer terminated by a perfluorinated core of various lengths. Their water solubility was found to be lower than 1 g/L irrespective of the length of both chains. The self-assembling properties of pure hybrids in water were studied by dynamic light scattering and transmission electron microscopy, which revealed the formation of two populations of aggregates with diameters of 8-50 nm and 80-300 nm. When mixed with the classical detergent n-dodecylmaltoside (DDM), the four hybrids were well soluble and formed small mixed micelles. DDM/hybrid mixtures were further evaluated for the extraction of the full-length, wild-type human GPCR adenosine receptor (A_2AR), and the bacterial transporter AcrB. The solubilization of A_2AR showed extraction efficiencies ranging from 40 to 70%, while that of AcrB reached 60-90%. Finally, three of the hybrids exhibited significant thermostabilization when present as additives. The derivative with a C₁₂-hydrogenated chain and a C₄F₉-fluorinated chain emerged as the most potent additive exhibiting both good extraction yields of A_2AR and AcrB and thermostabilization of A_2AR by ∼7 °C.