We have fabricated an unexpected type of supported planar bilayer composed of receptor phospholipids and single-chained diacetylenes as fluorogenic reporters using protruded anchor moieties with a positive terminal ch...We have fabricated an unexpected type of supported planar bilayer composed of receptor phospholipids and single-chained diacetylenes as fluorogenic reporters using protruded anchor moieties with a positive terminal charge.Nanoscale topographical and surface thermodynamic analyses,as well as molecular dynamics simulations,revealed the coexistence of well-dispersed liquid-condensed(L_(c))domains forming nano-islands and liquid-expanded(L_(e))region in the planar bilayer,enhancing sensitivity against a prototype of ubiquitous membrane-associated antimicrobial peptides,melittin.The L_(e)regions,acting as target receptors,enabled sensitive detection as the melittin adsorbed and inserted into these regions due to strong hydrophobic interactions between phospholipids and melittin.The L_(c)domains,serving as signal reporters,enabled diacetylenes to assemble,polymerize,and fluoresce in response to the insertion of melittin into the L_(e)regions.Thus,biphasic nanodomains of the planar lipid bilayer finally endowed this sensor system with a detection range of 100μMto 50 nM and a limit of detection(LOD)of∼37 nM for melittin.This exceeded the operational performance of the colorimetric polydiacetylene vesicle solution 45 times,which reportedly ranged from 100 to 4μM with an LOD of∼1.7μM.展开更多
基金This work was supported by the National Research Foundation of Korea(grant nos.NRF-2021R1A2C3009955 and 2017M3D1A1039421)and a Korea University Grant.
文摘We have fabricated an unexpected type of supported planar bilayer composed of receptor phospholipids and single-chained diacetylenes as fluorogenic reporters using protruded anchor moieties with a positive terminal charge.Nanoscale topographical and surface thermodynamic analyses,as well as molecular dynamics simulations,revealed the coexistence of well-dispersed liquid-condensed(L_(c))domains forming nano-islands and liquid-expanded(L_(e))region in the planar bilayer,enhancing sensitivity against a prototype of ubiquitous membrane-associated antimicrobial peptides,melittin.The L_(e)regions,acting as target receptors,enabled sensitive detection as the melittin adsorbed and inserted into these regions due to strong hydrophobic interactions between phospholipids and melittin.The L_(c)domains,serving as signal reporters,enabled diacetylenes to assemble,polymerize,and fluoresce in response to the insertion of melittin into the L_(e)regions.Thus,biphasic nanodomains of the planar lipid bilayer finally endowed this sensor system with a detection range of 100μMto 50 nM and a limit of detection(LOD)of∼37 nM for melittin.This exceeded the operational performance of the colorimetric polydiacetylene vesicle solution 45 times,which reportedly ranged from 100 to 4μM with an LOD of∼1.7μM.