Singh Ashok Kumar, Saxena Puja
Department of Chemistry, Indian Institute of Technology-Roorkee, Roorkee 247 667, India.
Anal Bioanal Chem. 2006 May;385(1):90-5. doi: 10.1007/s00216-006-0385-6. Epub 2006 Apr 7.
A polystyrene-based membrane of 7,8:16,17-dibenzo-6,9,15,18-tetraoxo-1,5,10,14-tetrathiacyclooctadeca-7,16-diene [Bz2Oxo4(18)dieneS4] was fabricated using sodium tetraphenylborate (NaTPB) and dioctyl phthalate (DOP) as anion excluder and plasticizing agent. The best performance was obtained from the membrane with the composition ionophore [Bz2Oxo4(18)dieneS4]:polystyrene:DOP:NaTPB, 5:100:150:10 (w/w). The response of the electrode was linear over a wide range of concentration, 1.26 x 10(-6)-1.00 x 10(-1) mol L(-1) for silver ion with a Nernstian slope of 58.4 +/- 0.1 mV per decade and a detection limit of 1.0 x 10(-6) mol L(-1). The electrode was found to be chemically inert and of adequate stability with a response time of 10 s and could be used for a period of 3 months without change of potential. It worked satisfactorily in mixtures containing up to 35% (v/v) non-aqueous content. The proposed membrane sensor had good selectivity for Ag+ over a wide variety of metal ions in the pH range 2.2-8.5. It was successfully used as an indicator electrode in potentiometric titration of silver ion. The electrode was also useful for determination of Ag+ in waste from photographic films.
以四苯硼酸钠（NaTPB）和邻苯二甲酸二辛酯（DOP）作为阴离子排除剂和增塑剂，制备了一种基于聚苯乙烯的7,8:16,17 - 二苯并 - 6,9,15,18 - 四氧代 - 1,5,10,14 - 四硫杂环十八碳 - 7,16 - 二烯[Bz2Oxo4(18)dieneS4]膜。对于组成比例为离子载体[Bz2Oxo4(18)dieneS4]:聚苯乙烯:DOP:NaTPB为5:100:150:10（w/w）的膜，获得了最佳性能。该电极在较宽的浓度范围内呈线性响应，对于银离子，浓度范围为1.26×10⁻⁶ - 1.00×10⁻¹ mol L⁻¹，能斯特斜率为每十年58.4±0.1 mV，检测限为1.0×10⁻⁶ mol L⁻¹。发现该电极化学惰性良好，稳定性足够，响应时间为10 s，可使用3个月而电位无变化。在非水含量高达35%（v/v）的混合物中能令人满意地工作。所提出的膜传感器在pH范围2.2 - 8.5内，对Ag⁺相对于多种金属离子具有良好的选择性。它成功地用作银离子电位滴定的指示电极。该电极还可用于测定摄影胶片废料中的Ag⁺。
