Highly sensitive determination of sulfonamides in environmental water samples by sodium dodecylbenzene sulfonate enhanced micro-solid phase extraction combined with high performance liquid chromatography

Sulfonamides are important antibiotics, and have achieved great applications. However they also impose serious threat on the environment and human health when they enter into environment by various ways. Present study developed a new determination method for six sulfonamides such as sulfadiazine, sulfamerazine, sulfamethazine, sulfadimethoxine, sulfamethoxazole and sulfafurazole in water samples, which was based on micro-solid phase extraction (mu-SPE) using TiO2 nanotube arrays as the adsorbent in combination with high performance liquid chromatography. Surfactant sodium dodecylbenzene sulfonate (SOBS) was used to enhance the extraction performance in this enrichment procedure. The parameters that affected the extraction efficiency had been investigated. Under the optimal conditions, it was observed that there were good linear relationships between the peak areas and the concentrations of the sulfonamides. The linear ranges were 1-200 mu g L-1 for the six sulfonamides with the correlation coefficients in the range of 0.998-0.999. The repeatability of the proposed method was satisfactory in the range of 2.1-4.4% (RSD, n=6). The limits of detection (LODs) were in the range of 0.27-0.6 mu g L-1. The proposed method was validated with real environmental samples, and the spiked recoveries were satisfied. These results indicated that the proposed method was a good tool for monitoring sulfonamides in the water samples. (C) 2015 Elsevier B.V. All rights reserved.