基于亮蓝为显色剂的高酸度试纸

研究了色素亮蓝对氢离子浓度大于1 mol/L溶液的颜色响应及其变色机理,并将其作为显色剂应用于高酸度试纸的研发。 研究表明,固定于改性基纸上的亮蓝处于氢离子浓度为0.1~9.0 mol/L范围的介质溶液中时,其颜色变化表现出明显的酸度响应特征,即随着溶液酸度的提高,亮蓝逐渐由蓝色转化为蓝绿色、绿色、黄绿色直至黄色。 该响应具有普适性,不受无机酸的种类与氧化性强弱的影响。 采用分光光度法研究了溶液酸度对亮蓝光吸收特性的影响,提出其可能的变色机理。 以亮蓝为显色剂开发出高酸度试纸,该试纸可以直接检测溶液中0.1~9.0 mol/L范围内的氢离子平衡浓度,精确度为±1 mol/L。

High Acidity Test Paper Based on Brilliant Blue as Color Agent

The color response of brilliant blue to the acidity of solutions(H⁺ concentration >0.1 mol/L) and the mechanism were studied using a prepared high acidity test paper. The results show that the colors of dissolved or fixed brilliant blue vary with the change of the acidity of solutions. It turns regularly from blue, green, kelly to yellow with the increase of H⁺ equilibrium concentration from 0.1 to 9.0 mol/L in the solution. The color transition only depends on the acidity of the solution and is unaffected by the acid type or its oxidation. The absorption phenomena between the color variation of brilliant blue and solution acidity were investigated by spectrophotometry, and the mechanism was also proposed. The high acidity paper was prepared based on the color response of brilliant blue to the acidity. It can be used to directly detect the H⁺ concentration of the solution in the range of 0.1~9.0 mol/L with the accuracy of ±1 mol/L.