[Determination of trace amounts of oxytetracycline in surface water samples by bubble enrichment-high performance liquid chromatography].

A method was established to determine the trace amounts of oxytetracycline (OTC) in surface water samples by bubble enrichment-high performance liquid chromatography (HPLC). A novel sample pretreatment method, bubble enrichment, was used to enrich trace amounts of oxytetracycline in aqueous solutions, and the effects of bubble enrichment conditions on the enrichment efficiency was investigated. Enrichment factor of oxytetracycline had a maximum of 37.06, RSD was 4.8% (n=11), and LOD was 0.038 mg/L under the optimized conditions of bubble enrichment and chromatography. The method was applied to the determination of oxytetracycline in surface water samples, with an average recovery of 101.9%. It is obvious that bubble enrichment has a positive effect on the enrichment of oxytetracycline, and hence, can be combined with chromatography to realize rapid, sensitive, and accurate detection of oxytetracycline in surface water samples. Additionally, the bubble enrichment method used in this paper does not require any organic solvent for the pretreatment of samples, and furthermore, the device is simple, inexpensive, and easy to operate; therefore, it is a very green sample pretreatment method with great research and promotion value. It is expected to be applicable to the analysis of other trace substances in complex samples.