Detection of metal ions using a wavelength interrogation surface plasmon resonance sensor with calix[4]arene derivatives as sensing films

A wavelength interrogation surface plasmon resonance (SPR) sensor with gold substrate modified with calix[4]arene derivative as sensing film was used to detect metal ions in aqueous solutions. We found that only Ag+ and Cu2+ could be selectively detected with the detection limit Of 10(-7) mol/L and 10(-4) mol/L, respectively. XPS data confirmed the presence of Au-S bond between the calixarene derivative and the gold substrate and complexation between the calixarene derivative and Ag+ or Cu2+.