Research On The Degradation Of Iron And Its Oxides On The Antibiotic Of Beta-lactam

Antibiotics are generally produced by microorganisms?including bacteria,fungi,actinomycetes,etc.?or higher animals and plants in the life process produced by a class of anti-pathogenic metabolites.As a new type of pollutants in the environment of antibiotics,human health and ecological environment poses a very serious threat.The widely used antibiotics,?-lactam antibiotics are easily oxidized and hydrolyzed by certain metal ions like copper.Fe???is the most common metal ion in the environment,but the role of ferric ion on the conversion and fate of?-lactam antibiotics in the environment is not yet clear.In this paper,the representative Fe element was selected as the research object to study the degradation of?-lactam antibiotics.Ampicillin?AMP?,the most widely used?-lactam antibiotic,was selected as the reaction substrate.Specific content includes:?1?The study shows that Fe???can promote the degradation of?-lactam antibiotics in aquatic environment.The degradation rate of AMP showed a linear increase with the increase of Fe???concentration.When the concentration of AMP was higher than Fe???,the degradation rate of antibiotics was no longer affected by the concentration of AMP.Fe???has the most favorable effect on the degradation of AMP under neutral p H condition.The effect of Fe???in promoting AMP degradation in practically surface and wastewater matrices is also evident.Of the different?-lactam antibiotics,Fe???promotes penicillin degradation faster than cephalosporins.Product analysis of AMP showed that there was no oxidation product in the AMP product,and only two wasomers of the hydrolyzate were observed.The effect of Fe???on AMP may be due to the fact that Fe promotes the hydrolysis of the?-lactam ring by complexing with the carboxyl and tertiary nitrogen of the?-lactam antibiotic.?2?Based on the degradation of?-lactam antibiotics by Fe???in aquatic environment,the effect of Fe₃O₄ on AMP degradation was studied.The results showed that the degradation rate of AMP showed a linear increase with the increase of Fe₃O₄ concentration,and the rate of AMP degradation was independent of the initial concentration of AMP.Fe₃O₄ has the most favorable effect on AMP degradation under acidic pH conditions.Fe₃O₄ on the degradation of different?-lactam antibiotics have a certain role in promoting.In actual surface water and wastewater matrix,the promotion effect of AMP degradation is also obvious.Oxygen has a certain role in promoting degradation of AMP.?3?The synergistic effect of metal chelate ethylenediaminetetraacetic acid?EDTA?and ferric oxide?Fe₃O₄?on AMP antibiotics was studied.The results showed that the synergistic effect of EDTA and Fe₃O₄ on the degradation of AMP was obvious.The degradation rate of AMP increased with the increase of Fe₃O₄ concentration and decreased with the increase of EDTA concentration.The degradation rate of AMP had nothing to do with the initial concentration of AMP.Synergistic effect of EDTA on Fe₃O₄ was the best under acidic pH conditions.The synergistic effect of EDTA and Fe₃O₄ degradation can promote the degradation of different?-lactam antibiotics.Under anaerobic conditions,the decrease in AMP concentration is almost only the amount of AMP adsorbed by the system.