Hybrid lipid bilayer platform with restricted flip-flop for probing surfactant-induced membrane disruption: towards biofouling-resistant membranes

Background Supported lipid membrane platforms are useful biosensing interfaces although surfactants such as sodium dodecyl sulfate (SDS), lauric acid (LA), and glycerol monolaurate (GML) disrupt them. Controlling disruption might improve membrane durability and modulating interleaflet membrane translocation (flip-flop), which is often involved in surfactant activity, is an attractive strategy. Methods Inspired by nanoarchitectonics principles, we fabricated hybrid lipid bilayers (HLBs) exclusively composed of double-chain phospholipids that restrict flip-flop and better mimic membrane packing than conventional HLBs with lower leaflets composed of single-chain alkanethiols. We also tested supported lipid bilayers (SLBs), which permit flip-flop. Quartz crystal microbalance-dissipation (QCM-D) experiments were performed to investigate how SDS, LA, and GML affect HLB and SLB platforms. Changes in membrane mass and viscoelastic properties were temporally tracked across tested surfactant concentrations. Findings SDS fully solubilized SLBs (∼100%) yet only modestly disrupted HLBs (∼15%). Similarly, LA and GML induced significant SLB remodeling but had attenuated effects on HLBs based on appreciably smaller QCM-D responses. These differences are attributed to restricted flip-flop and reduced interleaflet coupling in the HLB platform. Collectively, our findings support that membrane-disruptive surfactants have weakened interactions against double-chain HLBs compared to SLBs, thereby establishing mechanistic insights to aid design of durable membrane platforms.