双波长分光光度法测定饮料中亮蓝和胭脂红

Simultaneous Determination on Brilliant Blue and Carmine by Dual Wavelength Spectrophotometry

建立了双波长紫外-可见分光光度法联合测定2种食用色素亮蓝和胭脂红的新方法。亮蓝和胭脂红有很好的光吸收特性,最大吸收波长分别为629.0nm和509.0nm,并且双组分在各自的最大吸收波长处的吸收互不干扰,因而可实现双组份的同时测定。在2.00×10-6～3.00×10-5 mol/L范围内,亮蓝的浓度与其吸光度呈良好的线性关系,线性回归方程A=1.07×105c+0.067(相关系数r=0.997),检出限为1.00×10-6 mol/L;在1.00×10-6～1.600×10-5 mol/L范围内,胭脂红的浓度与其吸光度呈良好的线性关系,线性回归方程A=1.55×104c+0.023(相关系数r=0.999),检出限为1.00×10-5 mol/L。利用本方法测定了2种市售饮料中亮蓝和胭脂红的含量,加标回收率分别为97.0%和97.5%。

A new method of simultaneous determining edible pigment brilliant blue and carmine was established by dual wavelength spectrophotometry. The two pigments have very good light absorption phenomenon in aqueous solution,maximum absorption wavelength were 629.0 nm and 509.0 nm respectively. In the range of 2.00×10^-5～3.00×10^-5mol/L, the concentration and absorbance of the brilliant blue presented linear relations, equation of linear regression was A=1.07×10sc＋0.067（r=0. 998） ,the detection limits was 1.00×10^-6mol/L. In the range of 1.00×10^-6～1.600×10^-5mol/L, the concentration of carmine was linear relation with its absorbance, equation of linear regression was A=1.55×10^4c＋0.023（r=0. 999）, the detection limits was 1.00×10^-5mol/L. The targets pigments in two kinds of drink were determined by the method, the results showed the adding standard recovery were 97.0%-97.5%.