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[Display omitted] • Sonolytic degradation of the model antibiotics (ABX) in water is faster than in milk. • ABX with high hydrophobicity favours their sonolysis in water and milk. • ABX are mainly oxidized by •OH, and additive H 2 O 2 enhances the sonolysis. • No obvious change in nutrients in milk were observed after sonication. • No antimicrobial activity in milk were determined after sonication. Antibiotics (ABX) residues frequently occurred in water and cow milk. This work aims to understand the kinetics and mechanisms of sonolytic degradation of four ABX, i.e. ceftiofur hydrochloride (CEF), sulfamonomethoxine sodium (SMM), marbofloxacin (MAR), and oxytetracycline (OTC) in water and milk. In both water and milk, the sonolytic degradation of ABX follows pseudo-first order (PFO) kinetics well (R 2: 0.951–0.999), with significantly faster ABX degradation in water (PFO kinetics constants (k 1): 1.5 × 10−3-1.2 × 10−1 min−1) than in milk (k 1 : 3.5 × 10−4-5.6 × 10−2 min−1). The k 1 values for SMM degradation in water increased by 118% with ultrasonic frequency (40–120 kHz), 174% with ultrasonic frequency (80–500 kHz), 649% with ultrasonic power (73–259 W), 22% with bulk temperature (12–40℃), and by 68% with reaction volume (50–250 mL), respectively, in other things being equal. The relevant k 1 values in milk increased by 326%, 231%, 122%, 10% as well as 82% with the above same effective factors, respectively. The oxidation by free radicals generated in situ dominates ABX degradation, and the hydrophobic CEF (54.0–971.7 nM min−1) and SMM (39.2–798.4 nM min−1) underwent faster degradation than the hydrophilic MAR (33.9–751.9 nM min−1) and OTC (33.8–545.3 nM min−1) in both water and milk. Adding an extra 0.5 mM H 2 O 2 accelerated SMM degradation by 19% in water and 33% in milk. After 130–150 min sonication of 100 mL of 2.0 mg L−1 (6.62 μ M) SMM in various milk with 500 kHz and 259 W, the residue concentrations (52.9–96.3 μ g L−1) can meet the relevant maximum residue limit (100 μ g L−1). [ABSTRACT FROM AUTHOR]

Simple preconcentration and cleanup of trace antibiotics in milk using activated carbon (AC)-based solid phase extraction for HPLC analysis. [Display omitted] • Coconut powder activated carbon (CPAC, 10–15 mg) can be used as adsorbent for SPE. • Trace antibiotics (ABX) in water and milk were effectively recovered by CPAC-SPE. • Co-solvent 30% NH 4 OH/EtOH (or n -PrOH) was appropriate eluent for recovering ABX. • EDTA added in milk ensured smooth milk flow through CPAC and increased REs. • Commercial SPE cartridge, chemical deproteinization and tedious steps were avoided. CPAC-SPE-HPLC (coconut powdered activated carbon -SPE- HPLC) has been developed for the determination of antibiotic (ABX), sulfamonomethoxine sodium (SMM), oxytetracycline (OTC), ceftiofur hydrochloride (CEF) and marbofloxacin (MAR), in water and milk. Over 99.0% SMM and OTC were recovered from 20 mL of 0.5 μg/mL ABX solution using 10 mg-CPAC for adsorption and 2 mL of 30% NH 4 OH/EtOH (1/19 v/v) for elution. Similarly, over 99.0% CEF and MAR were recovered using 15 mg-CPAC and 2 mL of 30% NH 4 OH/ n -PrOH (1/19 v/v). Moreover, the recovery efficiencies of various ABX from 5 to 80 mL of 0.02–2.00 μg/mL medicated milk containing 10 mM EDTA are ordered as follows: OTC (99.3%), SMM (99.1%) > CEF (68.9%) > MAR (61.4%). No interference towards HPLC analysis were observed with elution using 2 mL of 30% NH 4 OH/EtOH (1/19 v/v). Furthermore, much lower limit of detections (0.02 μg/mL) than the maximum residual limits from European Commission (0.075–0.100 μg/mL) were obtained. [ABSTRACT FROM AUTHOR]

Note: US, Ultrasound; PS, peroxydisulfate; PS, peroxymonosulfate. The sonication-involved processes in water matrices. [Display omitted] • The generation of •OH radicals by ultrasound is insufficient to cause significant antibiotics cleavage. • Sonication improves mass transfer and oxidation with Fenton reagents, S 2 O 8 2−, HSO 5 − and O 3. • Sonophotocatalysis remarkably enhances antibiotics mineralization and detoxification. Antibiotic residues in water are general health and environmental risks due to the antibiotic-resistance phenomenon. Sonication has been included among the advanced oxidation processes (AOPs) used to remove recalcitrant contaminants in aquatic environments. Sonochemical processes have shown substantial advantages, including cleanliness, safety, energy savings and either negligible or no secondary pollution. This review provides a wide overview of the different protocols and degradation mechanisms for antibiotics that either use sonication alone or in hybrid processes, such as sonication with catalysts, Fenton and Fenton-like processes, photolysis, ozonation, etc. [ABSTRACT FROM AUTHOR]

Over the past few decades, antibiotics have been considered emerging pollutants due to their persistence in aquatic ecosystems. Even at low concentrations, these pollutants contribute to the phenomenon of antibiotic resistance, while their degradation is still a longstanding challenge for wastewater treatment. In the present literature survey, we review the recent advances in synergistic techniques for antibiotic degradation in wastewater that combine either ultrasound (US) or hydrodynamic cavitation (HC) and oxidative, photo-catalytic, and enzymatic strategies. The degradation of sulfadiazine by HC/persulfate (PS)/H2O2/α-Fe2O3, US/PS/Fe0, and sono-photocatalysis with MgO@CNT nanocomposites processes; the degradation of tetracycline by US/H2O2/Fe3O4, US/O3/goethite, and HC/photocatalysis with TiO2 (P25) sono-photocatalysis with rGO/CdWO4 protocols; and the degradation of amoxicillin by US/Oxone®/Co2+ are discussed. In general, a higher efficiency of antibiotics removal and a faster structure degradation rate are reported under US or HC conditions as compared with the corresponding silent conditions. However, the removal of ciprofloxacin hydrochloride reached only 51% with US-assisted laccase-catalysis, though it was higher than those using US or enzymatic treatment alone. Moreover, a COD removal higher than 85% in several effluents of the pharmaceutical industry (500–7500 mg/L COD) was achieved by the US/O3/CuO process. [ABSTRACT FROM AUTHOR]