摘要
利用超高效液相色谱-四极杆-飞行时间质谱(UPLC-Q-TOF/MS)快速与高分辨的分析优势,通过系统地考察样品制备、仪器分析中影响维生素C响应灵敏度和稳定性的各主要因素,建立了果蔬中维生素C的定量分析方法。果蔬样品在干冰保护下高速匀浆获得均匀的匀浆液,用0.1%(v/v)甲酸溶液提取后,采用Waters Acquity-UPLC T3色谱柱(100 mm×2.1 mm,1.8μm)分析,柱温为30℃,进样量为5μL,流动相为0.05%(v/v)甲酸-甲醇溶液(8∶2,v/v),流速为0.25 mL/min。提取的定量离子为[M-H]-(m/z 175.023 8),定性离子为[M-C_3H_4O_3]^-(m/z87.007 7),质量允许误差为5×10^(-6)(5 ppm)。结果表明:维生素C在0.02~5.0 mg/L范围内峰面积与质量浓度呈线性,线性相关系数(R2)为0.999 2;检出限及定量限分别为0.008 mg/L(S/N=3)和0.02 mg/L(S/N=10);在不同添加水平下,维生素C的平均回收率为89.3%~113%,相对标准偏差小于5.40%。在优化的条件下,对32批次的国产和新西兰猕猴桃样品进行检测,国产猕猴桃中维生素C的含量范围为498~1 625 mg/kg,新西兰进口猕猴桃中维生素C的含量范围为247~449 mg/kg。该方法操作简便,重复性良好,可用于果蔬中维生素C含量的准确测定。
A method was developed for the determination of vitamin C in fruits and vegetables by ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry. The main factors which affect the sensitivity and stability of vitamin C in the sample preparation and instrument analysis were investigated. Fruit and vegetable samples were prepared by high speed homogenate under the protection of dry CO2, and then extracted by 0. 1% （v/v ） formic acid solution. The analysis was performed using an Acquity-UPLC T3 column （100 mm×2. 1 mm, 1. 8 μm） with the column temperature of 30 The injection volume was 5 μL. The mobile phase consisted of 0. 05% （v/v ） formic acid solution and methanol with a volume ratio of 8 ：2. The flow rate was set at 0. 25 mL/min. The extracted ion [ M-H]- （m/z 175. 023 8） was selected for quantification, while extracted ion [M-C3H4O3]- （m/z 87. 007 7） was selected for qualifi-cation. The mass error was 5×10-6 （5 ppm）. The results displayed that the linearity of vitamin C ranged from 0. 02 to 5. 0 mg/L with the correlation coefficient （R2） of 0. 999 2. The limit of detection （LOD） and the limit of quantification （LOQ） were 0.008 mg/L （S/N =3） and 0.02 mg/L （ S/N=10）, respectively. The recoveries of the vitamin C in the spiked samples ranged from 89. 3% to 113% with the RSD less than 5. 40%. The developed method was then utilized to analyze the real kiwifruit samples. The results showed that the contents of the vitamin C ranged from 498 to 1625 mg/kg for the domestic kiwifruit samples. Regarding the New Zealand kiwifruit samples, the contents of the vitamin C ranged from 247 to 449 mg/kg. The present method demonstrated the advantages of easy operation, good precision and repeatability, mak-ing it feasible for accurate determination of vitamin C in fruits and vegetables.
出处
《色谱》
CAS
CSCD
北大核心
2016年第11期1048-1054,共7页
Chinese Journal of Chromatography
基金
国家自然科学基金项目(31501556)
浙江省自然科学基金项目(LQ15B050001)
公益性行业(农业)科技专项(201503107)~~
关键词
超高效液相色谱-四极杆-飞行时间质谱
维生素C
果蔬
ultra performance liquid chromatography-quadrupole time- of- flight mass spectrom-etry （UPLC-Q-TOF/MS）
vitamin C
fruits and vegetables
