紫外分光光度法测定饮料中糖精钠的含量

摘要

亚甲基蓝与糖精钠所形成的缔合物在pH=7.0的Britton-Robinson(B-R)缓冲溶液中,运用紫外分光光度仪检测,在247 nm波长处有最大吸收峰,且吸收峰随糖精钠浓度的增加而增大,线性范围:0.08~44 ug/mL,检出限:0.004 ug/mL,回收率:98.17%~103.25%,相对标准偏差(n=6)小于5.0%. 实际样品的测定结果与国标法(高效液相色谱法)所测结果较吻合. 本法具有灵敏度高、线性范围宽、操作快速、简单、干扰少、节省试剂等特点,适合饮料中糖精钠含量的测定.%The formation of methylene blue and saccharin sodium complexes in pH=7.0 britton robinson buffer solution(B-R) had a maximum absorption at the wavelength of 247nm under the detection of spectrophotometer UV, and the absorption peak increased with the increase of the concentration of sodium saccharin. In the range of 0.08 to 44ug/mL, the absorbance and the concentration of sodium saccharin had a good linearity relationship, the detection limit was 0.004ug/mL, and the recovery rate was 98.17-103.25% with RSD's (n=6) less than 5.0%. The results of the determination of actual samples were consistent compared with national standard meth?od (HPLC). This method for the determination of saccharin sodium content in beverage was more appropriate be?cause of high sensitivity, wide linear range, quick and easy operation, less disturbance, saving reagent, etc.