3,5-二硝基水杨酸(DNS)法测定D-半乳糖醛酸含量的条件探索

目的]优化3,5-二硝基水杨酸(DNS)法用于测定D-半乳糖醛酸含量的条件。方法]通过单因素实验研究了3,5-二硝基水杨酸(DNS)法测定D-半乳糖醛酸含量的测定条件。结果]单因素试实结果表明,利用3,5-二硝基水杨酸法测定D-半乳糖醛酸含量的优化条件为:测定波长540 nm,DNS用量4.0 ml,反应温度100℃,反应时间5 min,最佳测定时间60 min内。此条件下回归方程y=1.0226x-0.2784,回归系数r=0.9997,平均回收率99.96%,D-半乳糖醛酸含量测定范围0.5~1.1 mg/ml,统计分析表明,该方程显著存在。结论]多次实验验证,该方法测定D-半乳糖醛酸含量时操作简单、准确度高、重复性好。

Exploration of the Determination Conditions of the Content of D-Galacturonic Acid with the Method of 3,5-dinitrosalicylic Acid(DNS)

Objective] The research aimed to optimize the conditions of determining the content of D-galacturonic acid by the method of 3,5-dinitrosalicylic acid(DNS).Method] In the single factor experiment,the conditions of determining the content of D-galacturonic acid by the method of 3,5-dinitrosalicylic acid(DNS) were studied.Result] The results of the single factor experiment indicated that by using the method of DNS,the optimal conditions were as follows: the detection wavelength was 540 nm,the dosage of DNS was 4.0 ml,the reaction temperature was 100 ℃,the reaction time was 5 min,and the optimal determination time was in 60 min.Under these conditions,the regression equation was y=1.022 6x-0.278 4,the regression coefficient was 0.999 7,the average recovery was 99.96%,and the determination range of the content of D-galacturonic acid was from 0.5 mg/ml to 1.1 mg/ml.The statistical analysis indicated that the equation existed notably.Conclusion] It was proved in many experiments that the method of DNS used to determine the content of D-galacturonic acid had the advantages of easy operation,high accuracy and good reproducibility.