A Pretreatment Method for Analysis of Available Tetracycline in Soils

ABSTRACT

A pretreatment method for detecting the available (water-soluble) tetracycline (TC) contents in soils was developed using a molecularly imprinted polymer (MIP) synthesized with TC as the template. The infrared spectroscopy, scanning electron microscopy, and TC sorption isotherms revealed a specific TC binding with the synthesized MIP in water. Upon extraction and concentration from water by the MIP, the target TC could be directly analyzed by high-performance liquid chromatography (HPLC). The parameters for the pretreatment method were optimized with TC-spiked water and soils, with observed TC recoveries from water and soils equal to 74.7 ± 4.6% to 95.5 ± 6.5% (n = 3) and 48.1 ± 3.3% to 72.1 ± 2.7% (n = 3), respectively. The detected available TC contents in three test soil samples were in the range of 2.3 ± 0.1 to 3.0 ± 0.1 μg/kg (n = 3), only13.8%-39.4% of the TC contents detected by the conventional solvent-extraction method coupled with a solid-phase extraction (SPE) technique. The observed TC distribution in a vertical soil profile indicated that the proposed method for available antibiotic content coupled with the total extracted antibiotic content via the conventional (organic-solvent) extraction can be utilized to evaluate the available TC level and its mobility in contaminated soils.

KEYWORDS:

• Tetracycline
• available content
• pretreatment method
• soils
• molecularly imprinted polymers

Acknowledgments

This research was supported by the National Natural Science Foundation of China (No. 41361072).

Disclosure of potential conflicts of interest

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research was supported by the National Natural Science Foundation of China (41361072, 21667028 and U1403381).