105674-91-7Relevant articles and documents
Kinetics of micellar effect of non-ionic surfactant on oxidative degradation of ciprofloxacin
Singh, Ajaya Kumar,Shrivastava, Alpa,Shrivastava, Dilip R.,Patel, Rajmani,Sachdev, Neerja
, p. 359 - 368 (2020)
Oxidative degradation kinetics of leading fluoroquinolone family drug ciprofloxacin (CIP) by chloramine-T (CAT) in TX-100 micelle media was studied spectrophotometrically at 275 nm and 298 K. In pseudo-first-order conditions the rate constant (kobs) decreased regularly with increasing [TX-100]. To understand the self-organizing activities of TX-100, CMC values in varying reaction conditions had been evaluated. The role of non-ionic surfactant in the oxidative degradation process of ciprofloxacin by chlorinating agent chloramine-T is explained in terms of mathematical model explained by Menger-Portnoy. The reaction showed first to zero order dependence on [CAT] and fractional order on [CIP]. Increasing [H+] decreased the rate of reaction. The effect of ionic strength and solvent polarity of the medium in reaction conditions were studied. The effects of added salts [HSO4Na], [KCl], [KNO3] and [K2SO4] had also been studied. The stoichiometry of the reaction determined was 1:2 and the oxidation products were identified by LC-EI-MS. The analysis of degradation product of ciprofloxacin evidently reveals that the piperazine moiety is active site for oxidation in the reaction. Activation parameters were studied to propose appropriate mechanism for the reaction.
Unrecognized role of humic acid as a reductant in accelerating fluoroquinolones oxidation by aqueous permanganate
Zhou, Yang,Hu, Jianpeng,Gao, Yuan,Song, Yang,Pang, Su-Yan,Jiang, Jin
supporting information, p. 447 - 451 (2021/08/10)
A great concern has been raised regarding the issue of fluoroquinolones (FQs) in the environment. In this work, the transformation of FQs by commonly used oxidant permanganate (Mn(VII)) in the absence and presence of humic acid (HA), ubiquitously existing in aquatic environments, was systematically investigated. Here, the catalytic role of in-situ formed MnO2 on Mn(VII) oxidation of FQs depending on solution pH and co-existing substrates was firstly reported. It was interestingly found that HA could appreciably accelerate FQs degradation by Mn(VII) at environmentally relevant pH. HA as a reductant in accelerating FQs by Mn(VII) oxidation was distinctly elucidated for the first time, where MnO2 in situ formed from the reduction of Mn(VII) by HA served as a catalyst. Similar products were observed in the presence versus absence of HA. Considering that the accelerating role of HA was related to its reducing ability, an activation method based on Mn(VII) and reductant (i.e., Fe(II), Mn(II) and (bi)sulfite) was proposed, which exhibited considerable potential for application in the treatment of FQs contaminated water.
Nitric oxide reactivity accounts for N-nitroso-ciprofloxacin formation under nitrate-reducing conditions
Brienza, Monica,Chiron, Serge,Manasfi, Rayana,Sauvêtre, Andrés
, (2020/08/21)
The formation of N-nitroso-ciprofloxacin (CIP) was investigated both in wastewater treatment plants including nitrification/denitrification stages and in sludge slurry experiments under denitrifying conditions. The analysis of biological wastewater treatment plant effluents by Kendrick mass defect analysis and liquid chromatography - high resolution - mass spectrometry (LC[sbnd]HRMS) revealed the occurrence of N-nitroso-CIP and N-nitroso-hydrochlorothiazide at concentration levels of 34 ± 3 ng/L and 71 ± 6 ng/L, respectively. In laboratory experiments and dark conditions, produced N-nitroso-CIP concentrations reached a plateau during the course of biodegradation experiments. A mass balance was achieved after identification and quantification of several transformation products by LC[sbnd]HRMS. N-nitroso-CIP accounted for 14.3% of the initial CIP concentration (20 μg/L) and accumulated against time. The use of 4,5-diaminofluorescein diacetate and superoxide dismutase as scavengers for in situ production of nitric oxide and superoxide radical anion respectively, revealed that the mechanisms of formation of N-nitroso-CIP likely involved a nitrosation pathway through the formation of peroxynitrite and another one through codenitrification processes, even though the former one appeared to be prevalent. This work extended the possible sources of N-nitrosamines by including a formation pathway relying on nitric oxide reactivity with secondary amines under activated sludge treatment.
Ciprofloxacin degradation in UV/chlorine advanced oxidation process: Influencing factors, mechanisms and degradation pathways
Deng, Jia,Wu, Guangxue,Yuan, Shoujun,Zhan, Xinmin,Wang, Wei,Hu, Zhen-Hu
, p. 151 - 158 (2018/11/24)
Ciprofloxacin (CIP) is a widely used third generation fluoroquinolone antibiotics, and has been often detected in wastewater treatment plants. Finding an effective way to remove them from wastewater is of great concern. Ultraviolet (UV)/chlorine advanced oxidation process (AOP) has many advantages in micropollutant removal. In this study, CIP degradation in UV/chlorine process was investigated. Only 41.2% of CIP was degraded by UV photolysis and 30.5% by dark chlorination in 30 min, while 98.5% of CIP was degraded by UV/chlorine process in 9 min. HCO3 ? had markedly inhibition, NO3 ? and SO4 2- had slight inhibition, and Cl? had a marginal inhibition on CIP degradation in UV/chlorine system. The degradation of CIP in UV/chlorine process was mainly attributed to the attack of reactive species. The relative contributions of hydrated electrons (eaq [rad]), hydroxyl radicals (HO[rad]), chlorine atoms (Cl[rad]), and UV photolysis were investigated. Under neutral condition in aqueous solution, CIP degradation had highest pseudo first-order reaction rate constant, in which eaq [rad] had the highest contribution, followed by Cl[rad], HO[rad], and UV photolysis. The intermediates and byproducts were identified and the degradation pathway was proposed. The total organic chlorine (TOCl) and biotoxicity were further assessed. CIP and natural organic matters (NOMs) were removed efficiently in real water. UV/chlorine showed the potential for the wastewater treatment containing CIP.
Photochemistry of 1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(piperazin-1-yl)quinoline-3- carboxylic acid (=ciprofloxacin) in aqueous solutions
Mella, Mariella,Fasani, Elisa,Albini, Angelo
, p. 2508 - 2519 (2007/10/03)
The 1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(piperazin-1-yl)quinoline-3- carboxylic acid (=ciprofloxacin; 1) undergoes low-efficiency (φ=0.07) substitution of the 6-fluoro by an OH group on irradiation in H2O via the ππ* triplet (detected by