流动注射分光度法快速检测甘蔗汁中的还原糖

Study on Flow Injection Spectrophotometric Method for Rapid Determination of Reducing Sugar in Sugarcane

研究基于DNS与还原糖氧化-还原反应,获得甘蔗汁中还原糖的流动注射光度检测方法。考察分析条件对还原糖检测的影响,最终确定的分析条件是:检测波长510 nm,进样体积350μL,内径0.5mm的显色反应圈长度8 m,反应温度80℃,样品流速0.4 mL/min,推动液流速0.4 mL/min,显色液流速0.2 mL/min。在优化的流动注射条件下,系统的线性范围0.2～10.0 mg/L,相对标准偏差(RSD)为2.43%,检测限为0.004 mg/L,加标回收率98.8%～104.3%。

The paper proposes a flow injection spectrophotometric method for rapid determination of reducing sugar in sugarcane, which is based on redox reactions of reducing sugar and 3, 5-dinitrosalicylic acid （DNS）. Chemical factors and FIA variables affecting the system are also discussed, the results were as follows： the detected wavelength was 510 nm, sample volume was 350 μL, the length of reaction coils was 8 m, temperature was 80 ℃, the flow rate of sample solution and carrier solution were both 0.4 mL/min, the flow rate of color reagent was 0.2 mL/min. Under the optimal conditions, the linear range of this method was 0.2-10.0 mg/L; the detection limit was 0.004 mg/L; the relative standard deviation（RSD） was 2.43%. The proposed method was applied to the determination of reducing sugar in sugarcane,recov- eries were between 98.8% and 104.3%.