The detection of the pollution level of antibiotics in Daliao River system is a meaningful work. Sixteen antibiotics (6 sulfonamides, 5 fluoroquinolones, 3 tetracyclines and 2 chloramphenicols) were simultaneously quantified with solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry ( LC-MS/MS). In the SPE procedure, methanol and 2% (v/v) ammonia/methanol were used as the elution solvents in sequence to reduce the elution volume and improve the recovery. The results showed that this method have good sensitivity and enrichment effect for the target antibiotics in aqueous water, the recoveries ranged from 69. 5% to 122. 6%, the detection limits ranged from 0. 05 ng/L to 0. 32 ng/L. Thirteen antibiotics were found in the river water of Daliao River water system. Sulfa antibiotics were widely distributed, in which sulfamethoxazole was detected in all the sampling sites. The concentration of fluoroquinolones was relatively high in some sampling sites. The highest detection concentration of enoxacin was 41.3 ng/L. The frequencies and concentrations of tetracyclines and chloramphenicols were lower. In the upper reaches of the river, the concentrations of the 4 types of antibiotics appeared lower, but around the large cities such as Shenyang City, Benxi City, Liaoyang City, the concentrations showed higher levels. The study indicated that the Daliao River water system suffered from the pollution of antibiotics to a certain extent.%采用固相萃取-液相色谱-串联质谱建立了水中磺胺( SAs)、氟喹诺酮(FQs)、四环素(TCs)和氯霉素(CAPs)4类共16种抗生素的同时定量分析方法.该方法采用正、负离子同时扫描模式,提高了分析速度；同时在固相萃取洗脱步骤中采用两种溶剂(甲醇及含氨水的甲醇)组合对目标抗生素进行洗脱,在减小洗脱溶剂用量的同时又提高了回收率.用此法对大辽河水系20个采样点的河水进行了定量检测.结果表明:该法对水体中的目标抗生素有较好的灵敏度和富集效果,方法回收率为69.5％ ～122.6％,检出限为0.05 ～0.32 ng/L.在大辽河水系河水中共检出4类13种抗生素的残留,其中磺胺甲基异恶唑在所有采样点都有检出；氟喹诺酮类抗生素的局部残留浓度相对较高；四环素和氯霉素的检出频率和检出浓度相对较低.在河流的上游,这4类抗生素的残留水平较低,而在大城市如沈阳、本溪、辽阳的周围残留水平较高.通过对大辽河水系河水中的抗生素污染水平进行系统的分析比较,所得数据说明大辽河水系存在一定程度的抗生素残留污染,今后对周边地区抗生素污染排放需要加强科学管理.
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