光纤传感微量样品抗羟自由基检测方法的建立及其应用

目的:建立微量样品羟自由基(·OH)的检测方法,并用于新疆葡萄树伤流液及金银花茶、罗布麻茶、茉莉茶、竹叶茶等样品的检测。方法:采用Mn²⁺-H₂O₂-EBT法,检测波长为560 nm,在2 mL的比色皿中,取缓冲溶液(NaB₄O₇-NaOH)300 μL,EBT 120 μL,Mn²⁺ 300 μL,H₂O₂ 150 μL,将体系体积用水补充至2.0 mL。Mn²⁺-H₂O₂-EBT法可作为检测抗氧化物质抗氧化活性的有效可行方法之一,为验证该方法对微量样品抗羟自由基(·OH)活性实时检测的可行性,以抗坏血酸对照。结果:实验结果表明,新疆葡萄树伤流液、金银花茶、罗布麻茶、茉莉茶和竹叶茶均具有较强的清除羟自由基(·OH)的生物活性功能,是一种很好的天然抗氧化及自由基清除剂。结论:微量样品抗羟自由基检测方法可行,实现吸光度测定的同时,对少量样品进行实时、恒温及震荡在线检测,连续观察吸光度的变化。

Objective:To establish a method for hydroxyl radical(·OH)detection in micro-sample,and determine the samples of bleeding sap of Xinjiang grape tree,Honeysuckle tea,Luobuma tea,Jasmine tea and Bamboo leaf tea.Methods:Mn²⁺-H₂O₂-EBT could be an effective and feasible method to determine the antioxidant activity of a substance.The system was consisted of 300 μL NaB₄O₇-NaOH,120 μL EBT,300 μL Mn²⁺,and 150 μL H₂O₂,then added distilled water to 2 mL.The absorbance of well mixed sample was detected at 560 nm.This study was going to test the feasibility of this method.In order to test the feasibility of the method of micro-sample anitihydroxyl radical(·OH)in active real-time detection,ascorbic acid was applied for comparison.Results:The results showed that,all those samples including bleeding sap of Xinjiang grape tree,Honeysuckle tea,Luobuma tea,Jasmine tea,and Bamboo leaf tea had a strong hydroxyl radical(·OH)scavenging effect,which was a good natural resistance to oxidation free radical remover.Conclusion:The results showed that the established method can be used in real-time detection,which is able to analyze micro-sample in series.