Samples of Vitamin C was extracted by sodium metaphosphate ,2,6- dichloro indophend oxidized dehydro-genation into phenol indigo type ascorbic acid, reacted with o - phenylendiamine in order to generate the flourescent material - quinoxaline. That the fluorescent intensity and dehydrogenation ascorbic acid is proportional to the concentration determine the content of VC in bacon. The fluorescence intensity of quinoxaline was detected by fluorescence spec-trophotometry with 360nm excitation wavelength and 430nm emission wavelength. The detection limit in bacon of this method was 0. 95 mg kg -1, RSD was 2.4%. The recovery rate of VC was between 87. 2% and 94. 3%. By using fluorescence spectrophotometer method and 2,4- dinitrophenylhydrazine colorimetric method determined the VC in the bacon simultaneously, there were no significant difference, but the fluorescence spectrophotometer method had higher precision. It is proved that determination of VC in bacon by fluorescence spectrophotometry is high sensitivity, speedi-ness and accurate.%样品中的VC用偏磷酸钠提取,经2,6-二氯靛酚氧化成脱氢型抗坏血酸后与邻苯二胺(OPDA)反应,生成具有荧光的喹喔啉(quinoxaline),其荧光强度与脱氢抗坏血酸的浓度在一定条件下成正比,以此测定腊肉中VC含量.荧光分光光度计在激发波长360nm,发射波长430nm测定喹喔啉荧光强度.该方法VC的检出限为0.95mg.kg-1,相对标准偏差(RSD) 2.4％,回收率在87.2％～94.3％之间.用荧光分光光度计法和2,4-二硝基苯肼比色法同时测定腊肉中VC,发现二者结果无显著差异,但荧光分光光度计法精密度高于2,4-二硝基苯肼比色法.实验证明,荧光分光光度计法测量腊肉中VC具有灵敏度高、快速、准确等优点.
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