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[Display omitted] • Synergistic efficiency of sonication with activated carbon in milk reached 1.8–4.0. • Surface area and dosage of activated carbon were crucial in sonocatalysis systems. • Antibiotics with higher hydrophobic suffered faster sonocatalytic degradation. • 0.5 mmol L−1 H 2 O 2 speeded antibiotics removal >0.25 and 1.0 mmol L−1. Herein, an efficient, simple and economical approach to remove antibiotics (ABX), i.e. ceftiofur hydrochloride, sulfamonomethoxine sodium (SMM), marbofloxacin and oxytetracycline by sonication with activated carbon (AC) from cow milk has been successfully implemented. The pseudo-first-order kinetics constants for the sonolytic and sonocatalytic degrading SMM are 0.036 and 0.093 min−1, respectively. The synergistic efficiency of removing ABX by using sonocatalysis reached 1.8–4.0. Hydrophobic ABX underwent faster degradation than hydrophilic ABX in sonocatalytic systems. Adding 0.5 mmol L−1 H 2 O 2 , the optimal concentration, improved the sonocatalytic degradation rates of ABX by 9.1%–28.5%. Surface area and dose of AC play crucial roles in the sonocatalysis of ABX. By sonicating 50 mL of 5.52 μ mol L−1 ABX in milk at 500 kHz and 259 W with 20 mg AC for 20–60 min resulted in residual ABX concentrations ranging from 42.6 to 95.1 μ g L−1, which meet the relative maximum residue limits set by European Commission. [ABSTRACT FROM AUTHOR]

[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]

Antibiotics (ABX) residues occur frequently in milk, causing considerable wastage of medicated milk and serious economic losses, and making the issue a burden for the dairy industry. Improper disposal of medicated milk harms dairy production, animal welfare, and the environment. This work studies the use of ozonation in a vortex reactor for removing ceftiofur hydrochloride (CEF), sulfamonomethoxine sodium (SMM), marbofloxacin (MAR) and oxytetracycline (OTC) from milk. In terms of residual concentration, O 3 efficiency and the degradation kinetics of the various O 3 -involving processes in the vortex reactor, ABX removal via ozonation is better using stronger vortexing, which induces hydrodynamic cavitation. CEF undergoes the fastest degradation, followed by SMM, MAR, and OTC. High ABX hydrophobicity favors ABX degradation via ozonation, O 3 /H 2 O 2 , and O 3 /Na 2 S 2 O 8. ABX oxidation by •OH at the O 3 gas-bubble/milk interface is the principle degradation pathway, except for MAR. ABX degradation follows pseudo-first-order kinetics and is affected by initial ABX concentration, O 3 concentration/flow rate, reaction temperature, and milk components to varying degrees. Under optimal ozonation conditions, ABX residues meet the maximum limits as set by the European Commission and no antimicrobial activity was observed. The decontaminated milk was therefore suggested to be reused as calf food, animal feed, organic fertilizer, etc. [Display omitted] • Antibiotic (ABX) residues in milk reach tolerance levels by O3 in a vortex reactor; • Vortex speed affect ABX removal efficiency; • ABX are mainly oxidized by •OH ignoring marbofloxacin and H2O2 enhances O3 processes; • High ABX hydrophobicity favors the ABX degradation by ozonation or hybrid O3/H2O2; • No antimicrobial activity was detected in the milk treated with O3 in vortex. [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]