论文部分内容阅读
溴邻苯三酚红(BPR)是一种优良的显色剂,在光度分析中应用较广。BPR因其分子的电活性基团(?)C=0,分子的吸附特性,又是络合吸附波的灵敏试剂。但由于BPR与金属离子形成络合吸附波的测定条件比较严格,一些二价,三价金属离子对测定方法的影响较大,分析中常需要预先分离,因此应用受到限制。我们发现铜(Ⅱ)与BPR在柠檬酸—柠檬酸三铵介质中,于-0.30V(vs·SCE)处产生一灵敏的络合吸附波,铜浓度在8×10~(-8)～1.9×10~(-6)mol·L~(-1)范围内与峰电流呈良好的线性关系。柠檬酸-柠檬酸三铵的存在,既可控制体系的pH,又用作掩蔽剂,使方法具备了简单、灵敏、抗干扰能力较强的特点,用于茶叶和标准物质猪肝中铜的测定,获得满意的结果。
Bromopyrogallol red (BPR) is an excellent developer that is widely used in photometric analysis. BPR because of its molecule’s electroactive group (?) C = 0, the adsorption properties of molecules, but also sensitive reagents complexed adsorption wave. However, due to the more stringent determination conditions for the formation of complex adsorption waves between BPR and metal ions, some divalent and trivalent metal ions have a great influence on the determination method and often need to be separated before analysis, thus the application is limited. We found that copper (Ⅱ) and BPR produced a sensitive complexation adsorption wave at -0.30V (vs · SCE) in citric acid-triammonium citrate solution with copper concentration of 8 × 10 -8 ~ In the range of 1.9 × 10 -6 mol·L -1, there is a good linear relationship with the peak current. Citric acid - the presence of triammonium citrate can control the pH of the system, but also as a masking agent, the method has the characteristics of simple, sensitive, strong anti-interference ability for the tea and the standard substance pig liver copper Determination, to obtain satisfactory results.