双波长催化光度法测定痕量亚硝酸根  

Determination of Trace Nitrite by Dual-indicator Catalytic Spectrophotometry

作　　者：唐清华[1] 陈玉静[1] 

机构地区：[1]鲁东大学化学与材料科学学院,山东烟台264025

出　　处：《分析科学学报》2010年第3期370-372,共3页Journal of Analytical Science

基　　金：鲁东大学科研基金(L20082901)

摘　　要：研究了在稀硫酸介质中,痕量亚硝酸根对溴酸钾氧化溴甲酚绿和甲酚红褪色的指示反应,通过测量440 nm和520 nm波长处催化反应体系和非催化反应体系吸光度的变化,建立了双波长双指示剂催化动力学光度法测定痕量亚硝酸根的新方法。在最佳实验条件下,亚硝酸根的浓度在0.008~0.120μg/mL之间与吸光度存在线性关系（r=0.9968）,方法检出限为0.0022μg/mL。该方法简单,灵敏度高,选择性好,用于实际样品中痕量亚硝酸根的测定,获得满意结果。A new dual-wavelength dual-indicator catalytic kinetic spectrophotometric method for the determination of trace NO-2 was proposed.This method was based on NO-2-catalyzing oxidation of bromocresol green and cresol red by KBrO3 in H2SO4 solution.The absorbance of the catalytic and non-catalytic systems at 440 nm and 520 nm were measured.Under the optimum conditions,the linear range was 0.008~0.120 μg/mL,and the detection limit was 0.0022 μg/mL.The method was very simple with high sensitivity and good selectivity.The method was applied to determine nitrite in food samples with satisfactory results.

关 键 词：催化光度法 亚硝酸根 溴甲酚绿 甲酚红 

分 类 号：O657.32[理学—分析化学]