蔗糖测定的紫外分光光度新方法研究及应用

A New UV-Spectrophotometric Method for the Determination of Sucrose

方法基于在酸性条件下,蔗糖水解生成果糖和葡萄糖,果糖受热破坏后,其产物在285nm处有较大的紫外吸收。通过试验,确定了最佳条件,并建立了测定蔗糖的新紫外分光光度法;其线性范围为0.27～31.2μg/mL,摩尔吸光系数ε为9.63×103L·mol-1·cm-1。该法简单、快速,准确度高,用于甘蔗汁中蔗糖含量的测定,结果满意。对蔗糖水解的机理进行了初步探讨。

In acidic medium, sucrose hydrolyzes to give glucose and fructose, and the fructose can be destroyed by heat to give a product having maximum adsorption peak at 285 nm. Based on these, a new UVspectrometric method for sucrose was developed. Its linear range was 0.27~31.22 μg/mL, detection limit was 0.27 μg/mL. This new method was rapid, accurate, and was applied to the determination of sucrose in cane juice with satisfactory results. The hydrolysis mechanism of sucrose was discussed briefly.