Difference in activities of phospholipase C for hydrolysis of lipid/alkanethiol dilayers and lipid monolayers formed on Au(111)

摘要

Double alyer capacitance (Cdl) measurements have been used for in situ monitoring of phospholipae C (PLC )activity at phsopholipid monolayers formed on Au(111) electrodes.The enzymatic hydrolysis of the phospholipid monolayers formed on a 1-hexanethiol self-assembled monolayer can be monitored as increse of Cdl of the electrode/solution interface.On the other hand,Cdl of Au(111) odified with 12-bis(11-mercaptoundecanoyl)-sn-glycero-3-phosphocholinemonolayer is constant with time in the presence of PLC,indicating that PLC,indicating that PLC is not active for the monolayer.The diference in the PLC activity between the two systems sugests that flexibility of the lipid molecules at the surface is important for the enzymeatic hydrolysis.