Properties of Calix4-Lead(Pb) Films Using Langmuir-Blodgett (LB) Technique as an Application of Ion Sensor

Calixarenes are promising compounds to be used as ionophores and for molecular recognition. Their ability to form Langmuir and Langmuir-Blodgett (LB) films is of great interest in order to obtain small sensor devices which incorporate an active nanometric film. Calix[4]arene (Calix4) has been used in this work and its ability to form Langmuir films has been shown. Calix4 forms monolayers but at higher compressions tends to form multilayers. The presence of ions in the subphase, as lead chloride salt solutions, leads to some changes in the surface pressure-area (П-A) isotherms and surface potential-area (ΔV-A) isotherms. The effective dipole moments (μ) of the calixarene molecules in the uncomplexed and complexed states has been calculated from the ΔV values by using Helmholtz equation. Some characteristics of the films and mean molecular area have been deduced from the isotherms graph.