PVC waveguide sensor for determination of ion concentration

A PVC optical thin-film waveguide sensor is proposed which can select a specific ion and measure its concentration depending on materials added into the waveguide membrane. In order to investigate the applicability of this sensor to Ca⁺⁺ and Na⁺ measurement, the waveguide was fabricated with poly vinyl chloride (PVC), bis ethyl hexyl phthalate (BEHP), lipophilic anionic dye (LAD-3), and ionophores (K23E1 for Ca⁺⁺ or C14DD16C5 for Na⁺). For this purpose, the authors applied the sensor to a sample solution whose CaCl₂ concentration was gradually altered. Also, the authors applied it to an NaCl solution. In this experiment, they found that this PVC thin film waveguide possessed good ray propagation for 488 nm argon laser radiation. In addition, it showed the chemical reaction to ion enough to select it and measure its concentration. These findings suggested that the proposed PVC waveguide ion sensor is applicable to various ions