Langmuir–Blodgett film of p-tert-butylthiacalix[4]arene modified glassy carbon electrode as voltammetric sensor for the determination of Ag+

The π–A isotherms and UV–vis spectra of the transferred films suggested that the monolayer of p-tert-butylthiacalix[4]arene can coordinate with Ag+ at the air–water surface. From these observations, a glassy carbon electrode coated with Langmuir–Blodgett film of p-tert-butylthiacalix[4]arene is designed for the determination of trace amounts of Ag+. Compared with bare glassy carbon electrode and modified glassy carbon electrode using direct coating method, the Langmuir–Blodgett film modified electrode can greatly improve the measuring sensitivity of Ag+. Under the optimum experimental conditions, the Langmuir–Blodgett film modified electrode in 0.1 mol L−1 HNO3 shows a linear voltammetric response in the range of 5.0 × 10−9–2.0 × 10−6 mol L−1 with detection limit 3.0 × 10−9 mol L−1 for Ag+. The high sensitivity, selectivity, and stability of this Langmuir–Blodgett film modified electrode also demonstrate its practical application for a simple, rapid and economical determination of Ag+ in water sample.