Determination of Cadmium Ions by Designing an Optode Based on Immobilization of Dithizone on a Triacetylecelluose Membrane in Polluted Soil and Water Samples

An optode for cadmium ion determination has been designed by immobilization of dithizone on triacetylcellose membrane. When the optode membrane is introduced into a real samples containing cadmium, there is a color change from green to red, making it possible to use the change in absorbance at 611 nm as the analytical signal. The sensor could be used in the range of 0.3-3 ${\mu}g\;ml^{-1}$ (2.67-26.67 ${\mu}M$) of $Cd^{2+}$ ions with a limit of detection of 0.025 ${\mu}g\;ml^{-1}$ (25 ng $ml^{-1}$). The response time of optode is within 15 min depending on the concentration of $Cd^{2+}$ ions. It can be easily and completely regenerated by dilute EDTA solution. The effect of different possible interfering species has been examined and was shown the optode has a good selectivity. The results obtained for the determination of cadmium ion in polluted soil and water samples using the proposed optode was found to be comparable with the well-established atomic absorption method.

카드뮴이온 검출을 위한 optode를 triacetylecelluose 막에 있어 dithizone을 고정에 의하여 디자인 되었다. Optode 막이 카드뮴을 포함하는 611 nm 에서 흡수 변화가 가능한 실제시료에 도입 되었을 때 녹색에서 붉은 색으로 색 변화가 일어났다. $Cd^{2+}$ 이온 검출은 검출한계가 0.025 ${\mu}g\;ml^{-1}$ (25 ng $ml^{-1}$)이고 0.3-3 ${\mu}g\;ml^{-1}$ (2.67-26.67 ${\mu}M$)범위에서 가능하였다. Optode의 반응 시간은 $Cd^{2+}$ 이온에 의존하여 15분 안 에서 일어 났다. 다른 간섭종의 효과에 대해 시험되었고 좋은 선택성을 보였다. 제안된 optode를 사용하 여 오염된 토양과 물시료에서 $Cd^{2+}$ 이온의 검출 결과는 잘 확립된 원자흡수법과 동등하게 얻을 수 있었다.