Simultaneous Extraction of Four Antibiotic Compounds from Soil and Water Matrices

Abstract

The incidence of antibiotic resistance is on the rise and becoming a major health concern. Analyzing the presence of antibiotic compounds in the environment is critical for determining the potential health effects for humans, animals, and ecosystems. For this study, methods were developed to simultaneously isolate and quantify four antibiotics important in human medicine (sulfamethoxazole—SMX, trimethoprim—TMP, lincomycin—LIN, and ofloxacin—OFL) in water and soil matrices. For water analysis, different solid phase extraction (SPE) cartridges (Oasis HLB plus and Phenomenex Strata-X) were compared. The Oasis HLB Plus SPE cartridge provided the highest and most consistent recoveries with 118 ± 5%, 86 ± 4%, 83 ± 5%, and 75 ± 1% for SMX, TMP, LIN, and OFL, respectively. For soil analysis, different pre-treatments (grinding and freeze-drying) and soil extraction methodologies (liquid-solid extraction and accelerated solvent extraction (ASE)) were compared. The ASE system resulted in the highest overall recoveries of SMX, TMP, LIN, and OFL with an optimal extracting solution of acetonitrile/water (v/v, 50:50, pH 2.8). When the soil was ground and freeze-dried, trimethoprim recovery increased and when soil was ground, but not freeze-dried, LIN and OFL recoveries increased, while sulfamethoxazole recoveries decreased when soil was ground and freeze-dried. Based on this research, matrix characteristics, especially pH, as well as the pKa’s and functional groups of the antibiotics need to be carefully considered when attempting to extract antibiotic compounds from a water or soil environment.

Investigation of 29 Antimicrobial Compounds in Soil Using Newly Developed UHPLC-MS/MS Method

“…Based on previously published papers, electrospray ionization (ESI+) in a positive mode was investigated in mass spectrometric analysis under the multiple reaction monitoring (MRM) mode to achieve the most abundant signal for each analyte [ 3 , 13 , 32 , 38 , 39 ]. For the target compounds, two transition products were monitored; for internal standards (IS), one transition was selected to improve quantitation and confirmation of the development method.…”

“…Several multi-component methods are available in the literature for the determination of various veterinary antimicrobial drugs in soil [ 3 , 10 , 11 , 12 , 13 , 14 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 ]. Most of them enable the determination of only one class of compounds [ 14 , 37 ] or one substance from different xenobiotic classes [ 38 ] or up to four different classes [ 10 , 11 , 12 , 13 , 32 , 33 ]; only a few of them enable the determination of many substances from different classes [ 35 , 36 ]. Frequently, the isolation of analytes is based on liquid–solid extraction (LSE) coupled with solid-phase extraction (SPE) using one [ 3 , 12 , 13 , 14 , 32 , 38 ] or a combination of two different cartridges [ 10 , 35 ].…”

“…Most of them enable the determination of only one class of compounds [ 14 , 37 ] or one substance from different xenobiotic classes [ 38 ] or up to four different classes [ 10 , 11 , 12 , 13 , 32 , 33 ]; only a few of them enable the determination of many substances from different classes [ 35 , 36 ]. Frequently, the isolation of analytes is based on liquid–solid extraction (LSE) coupled with solid-phase extraction (SPE) using one [ 3 , 12 , 13 , 14 , 32 , 38 ] or a combination of two different cartridges [ 10 , 35 ]. Most of the methods are based on LC-MS/MS (liquid chromatography-tandem mass spectrometry) analysis [ 3 , 10 , 13 , 35 , 38 ].…”

“…Frequently, the isolation of analytes is based on liquid–solid extraction (LSE) coupled with solid-phase extraction (SPE) using one [ 3 , 12 , 13 , 14 , 32 , 38 ] or a combination of two different cartridges [ 10 , 35 ]. Most of the methods are based on LC-MS/MS (liquid chromatography-tandem mass spectrometry) analysis [ 3 , 10 , 13 , 35 , 38 ].…”

“…Several multi-component methods are available in the literature for the determination of various veterinary antimicrobial drugs in soil [3,[10][11][12][13][14][31][32][33][34][35][36][37][38]. Most of them enable the determination of only one class of compounds [14,37] or one substance from different xenobiotic classes [38] or up to four different classes [10][11][12][13]32,33]; only a few of them enable the determination of many substances from different classes [35,36].…”