基于超高效液相色谱-二极管阵列检测器/四极杆-飞行时间串联质谱(UPLC-PDA/Q-TOF)技术，采取高分辨质谱-非目标性数据采集-自动谱峰识别策略，对按照国家卫生健康委员会发布的食品安全国家标准GB 5009.28-2016检测雪糕样品时的糖精钠假阳性干扰物质进行了鉴定。通过UPLC-PDA定位，MSE模式对样品进行质谱全信息在线采集，UNIFI数据处理软件对干扰物进行综合分析，推断该化合物的正负分子离子质荷比分别为180.0626和178.0506，通过进一步的结构解析，推测该化合物可能为马尿酸；MSMS模式使用标准物质对鉴定结果进行验证，结果表明，马尿酸与干扰物的保留时间偏差为0.02 min，分子离子和碎片离子质荷比均为178.0509和134.0623，具有相对一致的色谱行为和质谱行为，即确定该干扰物为马尿酸。本研究为糖精钠检测和未知化合物定性研究提供了一定的理论基础和技术支撑，对于乳制品企业产品质量控制具有重要意义。

The false-positives to the detection of sodium saccharin in ice creams (according to the National Food Safety Standard GB 5009.28-2016 issued by the National Health Commission of the People's Republic of China) were examined, based on the ultra high performance liquid chromatography-photo diode array detector/quadrupole-time of flight tandem mass spectrometry (UPLC-PDA/Q-TOF) and the high resolution mass spectrometry-nontarget data acquisition-automatic spectrum peak identification strategy. It could be inferred that the positive and negative molecular ion mass-to-charge ratios of the interfering compound were 180.0626 and 178.0506 respectively, through UPLC-PDA positioning, MSE mode for full-scale online acquisition of mass spectrometric samples, UNIFI data processing software comprehensive analysis of interferences; The compound was speculated to be hippuric acid based on further structural analysis. MSMS mode along with the standard substance were used to verify the identification results, and it was found that the variation in retention time between hippuric acid and the interfering substance was 0.02 min, with the same mass-to-charge ratios of molecular ions and fragment ions (178.0509 and 134.0623, respectively), and the same chromatographic and mass spectrometric behaviors. Thus, the interfering compound was identified as hippuric acid. This work provided certain theoretical foundation and technical support for the detection of sodium saccharin and the qualitative study on unknown compounds, therefore, is of great significance for relevant dairy industries to control product quality.

北京市工程实验室创新能力建设项目(京发改（审）[2017]184号)