建立了海水中9种大环内酯类抗生素同时测定的液相色谱-四极杆/静电场轨道阱高分辨质谱检测方法。采用Empore C₁₈固相萃取膜提取海水中大环内酯类抗生素，Hypersil GOLD C₁₈色谱柱分离，乙腈和0.005 mol·L^-1乙酸铵溶液[含0.1%（体积分数）甲酸]为流动相梯度洗脱。正离子模式下全扫描/数据依赖二级扫描（Full MS/dd-MS²）分析，提取一级质谱准分子离子的精确质量数用于定量分析，二级质谱特征子离子精确质量数用于进一步定性确证。结果表明：9种大环内酯类抗生素均在13 min内出峰，其质量浓度在1~500 μg·L^-1内与其峰面积响应值呈线性关系，方法的检出限（3S/N）为0.02~0.12 ng·L^-1。以空白海水为基体，在3个浓度水平下进行加标回收试验，测得回收率为79.0%~105%，测定值的相对标准偏差（n=6）小于7.5%。方法用于测定25个海水样品中9种大环内酯类抗生素的含量，罗红霉素（ROM）、克拉霉素（CLM）、阿奇霉素（AZM）、替米考星（TMC）均被不同程度地检出。

A method was established for the simultaneous determination of 9 macrolide antibiotics in seawater by liquid chromatography-quadrupole/electrostatic field orbitrap high resolution mass spectrometry. Empore C₁₈ solid phase extraction film was used to extract macrolide antibiotics from seawater. The analytes were seperated by Hypersil GOLD C₁₈ chromatographic column and gradient eluted with the mixtures of acetonitrile and 0.005 mol·L^-1 ammonium acetate solution[containing 0.1% (φ) formic acid], and analyzed in full scan/data dependent MS² (Full MS/dd-MS²) mode. The results showed that the retention times of 9 macrolide antibiotics were all within 13 min. Linearity relationships between values of mass concentration of 9 macrolide antibiotics and their peak area responses were kept in the range of 1-500 μg·L^-1, with detection limits (3S/N) in the range of 0.02-0.12 ng·L^-1. Recovery was tested by standard addition method using a negative seawater sample as matrix at the 3 concentration levels, giving values of recovery in the range from 79.0% to 105% and of RSDs (n=6) of determined values lower than 7.5%. The proposed method was applied to the determination of 9 macrolide antibiotics in 25 samples of seawater, and ROM, CLM, AZM, and TMC were detected in varying degrees.