Gatifloxacin (GFX) is a kind of chiral fluoroquinolones compound due to the methyl group at the C-3 position of the piperazine ring[1]. Although the enantiomers of GFX show similar levels of antimicrobial activity a...Gatifloxacin (GFX) is a kind of chiral fluoroquinolones compound due to the methyl group at the C-3 position of the piperazine ring[1]. Although the enantiomers of GFX show similar levels of antimicrobial activity and pharmacokinetics[2], the other biological activities (i.e., toxicity or enantioselective recognition to various receptors in vivo) of GFX enantiomers have not yet been studied. With this in mind, we developed a rapid and cost-effective high performance liquid chromatographic (HPLC) separation procedure for GFX enantiomers with a pre-column esterification strategy.展开更多
The aim of this study was to identify the potential antibacterial effects of gatifloxacin on periodontal pathogens including Aggregatibacter actinomycetemcomitans, Porphyromonas gingi-valis, and Prevotella intermedia....The aim of this study was to identify the potential antibacterial effects of gatifloxacin on periodontal pathogens including Aggregatibacter actinomycetemcomitans, Porphyromonas gingi-valis, and Prevotella intermedia. The minimum inhibitory concentrations (MIC) of gatifloxacin and its bactericidal effects were investigated. Gatifloxacin inhibited the growth of all three kinds of periodontopathic bacteria tested in broth. The MIC value of 2.5 nM was found to be the most effective in inhibiting A. actinomycetemcomitans. An adenosine triphosphate biolumi-nescence assay revealed that gatifloxacin exhibited bactericidal effects on the tested bacteria in a time-dependent manner. The safety of gatifloxacin in mammalian cells was evaluated by assessing the viability of normal human dermal fibroblast (NHDF) cells treated with gatifloxacin. Almost all NHDF cells survived after 2-d culture, while 81% of the cells survived after 4-d culture when treated with 1.0 × 10<sup>3</sup> nM gatifloxacin. These results indicate that gatifloxacin is a possible drug for local administration to prevent periodontal infection.展开更多
AIM: To reveal the cytotoxicity and related mechanisms of gatifloxacin(GFX) to stromal fibroblasts(SFs) in vitro.METHODS: SFs were treated with GFX at different concentrations(0.009375%-0.3%), and their viability was ...AIM: To reveal the cytotoxicity and related mechanisms of gatifloxacin(GFX) to stromal fibroblasts(SFs) in vitro.METHODS: SFs were treated with GFX at different concentrations(0.009375%-0.3%), and their viability was detected by MTT method. The cell morphology was observed using light/transmission electron microscope. The plasma membrane permeability was measured by AO/EB double-staining. Then cell cycle, phosphatidylserine(PS) externalization, and mitochondrial transmembrane potential(MTP) were analyzed by flow cytometry. DNA damage was analyzed by electrophoresis and immunostaining. ELISA was used to evaluate the caspase-3/-8/-9 activation. Finally, Western blotting was applied for detecting the expressions of apoptosis-related proteins.RESULTS: Morphological changes and reduced viability of GFX-treated SFs demonstrated that GFX above 0.009375% had cytotoxicity to SFs with dependence of concentration and time. GFX-treating cells also showed G1 phase arrest, increased membrane permeability, PS externalization and DNA damage, which indicated that GFX induced apoptosis of SFs. Additionally, GFX could activate the caspase-8, caspase-9, and caspase-3, induce MTP disruption, downregulate B-cell leukemia-2(Bcl-2) and B-cell leukemiaXL(Bcl-XL), and upregulate Bcl-2 assaciated X protein(Bax), Bcl-2-associated death promoter(Bad), Bcl-2 interacting domain(Bid) and cytoplasmic cytochrome C in SFs, suggesting that caspase-dependent extrinsic and intrinsic pathways were related to GFX-contributed apoptosis of SFs.CONCLUSION: The cytotoxicity of GFX induces apoptosis of SFs through triggering the caspase-dependent extrinsic and intrinsic pathways.展开更多
A kind of molecularly imprinted polymer (MIPs) with high selectivity was prepared using methacrylic acid (MAA) as functional monomer, ethylene glycol dimethacrylate (EDMA) as crosslinker and Gatifloxacin as template. ...A kind of molecularly imprinted polymer (MIPs) with high selectivity was prepared using methacrylic acid (MAA) as functional monomer, ethylene glycol dimethacrylate (EDMA) as crosslinker and Gatifloxacin as template. The effect of various parameters such as volume of solvent, functional monomer dosage, crosslinker dosage and polymerization time were investigated. The selective binding experiment for substrates show that the affinity and selectivity for Gatifloxacin were higher than that for blank polymer. Scatchard analysis show that the MIPs recognized template with two kinds of binding sites. The dissociation constant Kd and maximum adsorption quantity Qmax of these two kinds of binding sites were calculated: Kd1 and Qmax1 of the binding sites with high affinity were 8.67×10-4 mol/L and 28.19μmol/g, while Kd2 and Qmax2 of the binding sites with low affinity were1.05×10-3 mol/L and 33.20μmol/g respectively.展开更多
Postoperative endophthalmitis(POE)has been the most threatening complication after cataract surgery,which perhaps can be solved by the antibiotic-loaded intraocular lens(IOL).However,most drug-loaded IOLs demonstrate ...Postoperative endophthalmitis(POE)has been the most threatening complication after cataract surgery,which perhaps can be solved by the antibiotic-loaded intraocular lens(IOL).However,most drug-loaded IOLs demonstrate insufficient drug quantity,short release time,increased implantation-related difficulties or other noticeable drawbacks.To prevent POE and to address these deficiencies,a drug-loaded copolymer IOL,prepared from poly(urethane acrylate)prepolymer,isobornyl methacrylate(IBOMA),N-vinyl-2-pyrrolidone(NVP),Irgacure 819,RUVA-93,and gatifloxacin(GAT),was rapidly fabricated via photocuring and by using a 3D-printed mold.This composite displayed an outstanding and controllable GAT release behavior in vitro,a high light transmittance,and a moderate refractive index.Also,it demonstrated improved strain stress and elongation compared with the reference commercial acrylic IOL material.In vivo tests demonstrated satisfying released drug concentration at the early treatment stage.In vitro and in vivo studies further confirmed the remarkable bacterial inhibition and prevention of POE by the proposed IOL,which also displayed good biocompatibility.These findings suggested that the GAT-loaded IOL could be a promising implant to prevent and cure POE,also the proposed methods could inspire more designs for various medical applications.展开更多
Background Ophthalmic gel has been developed to increase the drug concentration in aqueous humor and to retard the loss of drug from the conjunctival sac.The research was to compare the drug concentration in aqueous h...Background Ophthalmic gel has been developed to increase the drug concentration in aqueous humor and to retard the loss of drug from the conjunctival sac.The research was to compare the drug concentration in aqueous humor of cataract patients administered 0.3% gatifloxacin ophthalmic gel with that in patients administered 0.3% gatifloxacin ophthalmic solution.Methods Ninety-six patients with cataract (96 eyes) were randomly assigned to 8 groups.The patients in groups 1-4received topical gatifloxacin 0.3% ophthalmic gel and those in groups 5-8 received gatifloxacin 0.3% ophthalmic solution.The dose regimen was 1 drop, 4 times a day for 3 consecutive days prior to cataract surgery.On the day of surgery, 1drop was applied at 15, 30, 60 or 120 minutes before commencement of cataract surgery in groups 1 and 5, groups 2 and 6, goups 3 and 7, and groups 4 and 8, respectively.Aqueous humor was extracted during the cataract surgery for the analysis of gatifloxacin concentration..Results The concentrations of gatifloxacin in aqueous humor were (0.24±0.25) μg/ml, (1.11±0.74) μg/ml, (2.32±2.01)μg/ml and (1.85±1.14) μg/ml in groups 1 to 4, and (0.16±0.25) μg/ml, (0.31±0.24) μg/ml, (0.75±0.28) μg/ml and (0.33±0.22) μg/ml in groups 5 to 8, respectively.Patients receiving gatifloxacin ophthalmic gel showed greater mean values of gatifloxacin concentration in aqueous humor than those receiving gatifloxacin solution, and such differences were significant with P 〈0.05 for all comparisons except that between groups 1 and 5.Conclusion Topical gatifloxacin ophthalmic gel can attain significantly greater drug concentrations in human aqueous humor than gatifloxacin ophthalmic solution.展开更多
To detect gatifloxacin(GAT)residue in swine urine,an electrochemical immunoassay was established.An indirect competitive immunoassay was developed,in which the coating antigen is immobilized in an enzyme-linked immuno...To detect gatifloxacin(GAT)residue in swine urine,an electrochemical immunoassay was established.An indirect competitive immunoassay was developed,in which the coating antigen is immobilized in an enzyme-linked immunosorbent assay(ELISA)plate and GAT residue from the sample competes with the limited binding sites in added anti-GAT antibody.Horseradish peroxidase(HRP)conjugated to goat anti-rabbit IgG was used as the enzymatic label.A carbon fiber working electrode was constructed and current signals were detected by using hydrogen peroxide as a substrate and hydroquinone as an electrochemical mediator.The electrochemical immunoassay was evaluated by analysis of GAT in buffer or swine urine and an average value of half inhibition concentration(IC50)of 8.9 ng/ml was obtained.Excellent specificity of the antibody was achieved with little cross-reaction with lomefloxacin(3.0%),ciprofloxacin(3.0%),and ofloxacin(1.9%)among commonly used(fluoro)quinolones.In conclusion,the immunoassay system developed in this research can be used as a rapid,powerful and on-site analytical tool to detect GAT residue in foods and food products.展开更多
At a weight ratio of n-C5H11OH/H2O=50/50, when the total content of sodium dodecyl sulfate (SDS) was less than 6.0%, the ternary mixture of SDS/n-C5H11OH/H2O coexisted in two immiscible microemulsions. The distribut...At a weight ratio of n-C5H11OH/H2O=50/50, when the total content of sodium dodecyl sulfate (SDS) was less than 6.0%, the ternary mixture of SDS/n-C5H11OH/H2O coexisted in two immiscible microemulsions. The distribution and transfer of gatifloxacin (GTFX) between the two phases were studied using UV-Vis and electrochemistry AC impedance spectra. The results show that GTFX transferred from the upper phase (W/O) to the lower phase (O/W or bicontinuous microemulsion), but a small amount of SDS transferred from the lower phase to the upper phase correspondingly with the increase of the total SDS content at a total GTFX concentration of 1.0×10^-5 mol/L. The addition of GTFX did not change the structures of the two different phases fundamentally, but resulted in the transfer and redistribution of GTFX and SDS, so the electric properties of the system were changed correspondingly.展开更多
Three novel isostructural complexes M(gatx)2(H2O)2·4H2O [gatx=gatifloxacin, M = Zn (1), Ni (2) and Co (3)] were synthesized at room temperature and structurally characterized by elemental analysis, IR a...Three novel isostructural complexes M(gatx)2(H2O)2·4H2O [gatx=gatifloxacin, M = Zn (1), Ni (2) and Co (3)] were synthesized at room temperature and structurally characterized by elemental analysis, IR and single crystal X-ray diffraction, which exhibit a similar mononuclear structure, in which the metal ion is coordinated by two gatifloxacin and two aqua ligands to furnish a distorted octahedral geometry, and show different activities against staphylococcus due to the different metal ions in the structures.展开更多
A novel high selective and sensitive fluorescence probe termed gatifloxacin was discovered based on fluorescence "on-off" phenomenon in the presence of Se(IV). In the Tris-HCl/acetonitrile(3:7, volume ratio, Tri...A novel high selective and sensitive fluorescence probe termed gatifloxacin was discovered based on fluorescence "on-off" phenomenon in the presence of Se(IV). In the Tris-HCl/acetonitrile(3:7, volume ratio, Tris-HCl 0.05 mol/L, pH=7.3) system, the fluorescence intensity of gatifloxacin was linearly decreased with the concentration increase of Se(IV) in a range of 1.0×10-5--5.0×10-5 mol/L with a correlation coefficient of 0.9979(R2=0.9958) and in a range of 5.0×10-5--1.0 ×10-4 mol/L with a correlation coefficient of 0.9973(R2=0.9946). The detection limit of Se(IV) was 1.70×10-6mol/L.展开更多
Fluoroquinolone antibiotics (FQs) are frequently detected as emerging pollutants in aqueous environments.In this study,kinetics,influencing factors and mechanisms on the photodegradation of gatifloxacin,a representati...Fluoroquinolone antibiotics (FQs) are frequently detected as emerging pollutants in aqueous environments.In this study,kinetics,influencing factors and mechanisms on the photodegradation of gatifloxacin,a representative FQ,were investigated.The photodegradation follows the pseudo-first-order kinetics.Gatifloxacin photodegrades with a quantum yield of (5.94 ± 0.95) × 10 3 in pure water and undergoes direct photolysis as well as self-sensitized photodegradation.The FQ photodegrades slower in freshwater and seawater than in pure water,which is attributed to the integrative effects of pH and the aqueous dissolved matter (e.g.,humic acids and NO 3-) on the photodegradation.A toxicity test using Vibrio fischeri revealed the formation of hazardous photoproducts.展开更多
The reactions between gatifloxacin(GFX) and various one-electron oxidants,such as ˙OH,N3˙,Br2˙ˉ,and SO4˙ˉ,have been studied by pulse radiolysis techniques.The GFX radical anion formed in the reaction of GFX with...The reactions between gatifloxacin(GFX) and various one-electron oxidants,such as ˙OH,N3˙,Br2˙ˉ,and SO4˙ˉ,have been studied by pulse radiolysis techniques.The GFX radical anion formed in the reaction of GFX with eaqˉ could either be protonated or deprotonated,and the absorption of GFX radical anion was located at 390 nm.The transient species produced by the reaction of GFX with ˙OH radical shows a broad band in the 380?600 nm region with a shoulder,while the oxidation by N3˙,SO4˙ˉ,and Br2˙ˉ results in an absorption band with λmax = 370 nm.At neutral condition(pH 7),the rate constants of GFX reacting with ˙OH,N3˙,Br2˙ˉ,SO4˙ˉ and eaqˉ are estimated to be 1.0 × 1010,3.1 × 109,2.8 × 109,3.0 × 109,and 1.8 × 1010 dm3 mol?1 s?1,respectively.From the pH dependence on the formation of electron adducts and on the rate constant of GFX with eaqˉ,the pKa of GFX radical anion is estimated to be 5.5 and 9.3.展开更多
基金supported by Guangdong Natural Science Foundation(S2013030013338)the Ph D.Programs Foundation of Ministry of Education of China(20114404130002)Guangdong Planed Program in Science and Technology(cgzhzd0808,2013B051000072,2012A020100002)
文摘Gatifloxacin (GFX) is a kind of chiral fluoroquinolones compound due to the methyl group at the C-3 position of the piperazine ring[1]. Although the enantiomers of GFX show similar levels of antimicrobial activity and pharmacokinetics[2], the other biological activities (i.e., toxicity or enantioselective recognition to various receptors in vivo) of GFX enantiomers have not yet been studied. With this in mind, we developed a rapid and cost-effective high performance liquid chromatographic (HPLC) separation procedure for GFX enantiomers with a pre-column esterification strategy.
文摘The aim of this study was to identify the potential antibacterial effects of gatifloxacin on periodontal pathogens including Aggregatibacter actinomycetemcomitans, Porphyromonas gingi-valis, and Prevotella intermedia. The minimum inhibitory concentrations (MIC) of gatifloxacin and its bactericidal effects were investigated. Gatifloxacin inhibited the growth of all three kinds of periodontopathic bacteria tested in broth. The MIC value of 2.5 nM was found to be the most effective in inhibiting A. actinomycetemcomitans. An adenosine triphosphate biolumi-nescence assay revealed that gatifloxacin exhibited bactericidal effects on the tested bacteria in a time-dependent manner. The safety of gatifloxacin in mammalian cells was evaluated by assessing the viability of normal human dermal fibroblast (NHDF) cells treated with gatifloxacin. Almost all NHDF cells survived after 2-d culture, while 81% of the cells survived after 4-d culture when treated with 1.0 × 10<sup>3</sup> nM gatifloxacin. These results indicate that gatifloxacin is a possible drug for local administration to prevent periodontal infection.
基金Supported by the National High Technology R&D Program of China(No.2006AA02A132)
文摘AIM: To reveal the cytotoxicity and related mechanisms of gatifloxacin(GFX) to stromal fibroblasts(SFs) in vitro.METHODS: SFs were treated with GFX at different concentrations(0.009375%-0.3%), and their viability was detected by MTT method. The cell morphology was observed using light/transmission electron microscope. The plasma membrane permeability was measured by AO/EB double-staining. Then cell cycle, phosphatidylserine(PS) externalization, and mitochondrial transmembrane potential(MTP) were analyzed by flow cytometry. DNA damage was analyzed by electrophoresis and immunostaining. ELISA was used to evaluate the caspase-3/-8/-9 activation. Finally, Western blotting was applied for detecting the expressions of apoptosis-related proteins.RESULTS: Morphological changes and reduced viability of GFX-treated SFs demonstrated that GFX above 0.009375% had cytotoxicity to SFs with dependence of concentration and time. GFX-treating cells also showed G1 phase arrest, increased membrane permeability, PS externalization and DNA damage, which indicated that GFX induced apoptosis of SFs. Additionally, GFX could activate the caspase-8, caspase-9, and caspase-3, induce MTP disruption, downregulate B-cell leukemia-2(Bcl-2) and B-cell leukemiaXL(Bcl-XL), and upregulate Bcl-2 assaciated X protein(Bax), Bcl-2-associated death promoter(Bad), Bcl-2 interacting domain(Bid) and cytoplasmic cytochrome C in SFs, suggesting that caspase-dependent extrinsic and intrinsic pathways were related to GFX-contributed apoptosis of SFs.CONCLUSION: The cytotoxicity of GFX induces apoptosis of SFs through triggering the caspase-dependent extrinsic and intrinsic pathways.
基金China National Science Foundation (No. 20877036)Jiangsu University Science Research Funding (No. 04JDG017).
文摘A kind of molecularly imprinted polymer (MIPs) with high selectivity was prepared using methacrylic acid (MAA) as functional monomer, ethylene glycol dimethacrylate (EDMA) as crosslinker and Gatifloxacin as template. The effect of various parameters such as volume of solvent, functional monomer dosage, crosslinker dosage and polymerization time were investigated. The selective binding experiment for substrates show that the affinity and selectivity for Gatifloxacin were higher than that for blank polymer. Scatchard analysis show that the MIPs recognized template with two kinds of binding sites. The dissociation constant Kd and maximum adsorption quantity Qmax of these two kinds of binding sites were calculated: Kd1 and Qmax1 of the binding sites with high affinity were 8.67×10-4 mol/L and 28.19μmol/g, while Kd2 and Qmax2 of the binding sites with low affinity were1.05×10-3 mol/L and 33.20μmol/g respectively.
基金the Program of National Natural Science Foundation of China[81870641,82070939]Key Research and Development Program of Zhejiang Province of China[2020C03035].
文摘Postoperative endophthalmitis(POE)has been the most threatening complication after cataract surgery,which perhaps can be solved by the antibiotic-loaded intraocular lens(IOL).However,most drug-loaded IOLs demonstrate insufficient drug quantity,short release time,increased implantation-related difficulties or other noticeable drawbacks.To prevent POE and to address these deficiencies,a drug-loaded copolymer IOL,prepared from poly(urethane acrylate)prepolymer,isobornyl methacrylate(IBOMA),N-vinyl-2-pyrrolidone(NVP),Irgacure 819,RUVA-93,and gatifloxacin(GAT),was rapidly fabricated via photocuring and by using a 3D-printed mold.This composite displayed an outstanding and controllable GAT release behavior in vitro,a high light transmittance,and a moderate refractive index.Also,it demonstrated improved strain stress and elongation compared with the reference commercial acrylic IOL material.In vivo tests demonstrated satisfying released drug concentration at the early treatment stage.In vitro and in vivo studies further confirmed the remarkable bacterial inhibition and prevention of POE by the proposed IOL,which also displayed good biocompatibility.These findings suggested that the GAT-loaded IOL could be a promising implant to prevent and cure POE,also the proposed methods could inspire more designs for various medical applications.
文摘Background Ophthalmic gel has been developed to increase the drug concentration in aqueous humor and to retard the loss of drug from the conjunctival sac.The research was to compare the drug concentration in aqueous humor of cataract patients administered 0.3% gatifloxacin ophthalmic gel with that in patients administered 0.3% gatifloxacin ophthalmic solution.Methods Ninety-six patients with cataract (96 eyes) were randomly assigned to 8 groups.The patients in groups 1-4received topical gatifloxacin 0.3% ophthalmic gel and those in groups 5-8 received gatifloxacin 0.3% ophthalmic solution.The dose regimen was 1 drop, 4 times a day for 3 consecutive days prior to cataract surgery.On the day of surgery, 1drop was applied at 15, 30, 60 or 120 minutes before commencement of cataract surgery in groups 1 and 5, groups 2 and 6, goups 3 and 7, and groups 4 and 8, respectively.Aqueous humor was extracted during the cataract surgery for the analysis of gatifloxacin concentration..Results The concentrations of gatifloxacin in aqueous humor were (0.24±0.25) μg/ml, (1.11±0.74) μg/ml, (2.32±2.01)μg/ml and (1.85±1.14) μg/ml in groups 1 to 4, and (0.16±0.25) μg/ml, (0.31±0.24) μg/ml, (0.75±0.28) μg/ml and (0.33±0.22) μg/ml in groups 5 to 8, respectively.Patients receiving gatifloxacin ophthalmic gel showed greater mean values of gatifloxacin concentration in aqueous humor than those receiving gatifloxacin solution, and such differences were significant with P 〈0.05 for all comparisons except that between groups 1 and 5.Conclusion Topical gatifloxacin ophthalmic gel can attain significantly greater drug concentrations in human aqueous humor than gatifloxacin ophthalmic solution.
基金supported by the National High-Tech R&D Program(863)of China(Nos.07AA10Z435 and 2007AA06A407)the National Natural Science Foundation of China(No.20675048)+1 种基金the Fundamental Research Funds for the Central Universities(No.65011121)the Shandong Provincial Natural Science Foundation(No.Y2008B31),China
文摘To detect gatifloxacin(GAT)residue in swine urine,an electrochemical immunoassay was established.An indirect competitive immunoassay was developed,in which the coating antigen is immobilized in an enzyme-linked immunosorbent assay(ELISA)plate and GAT residue from the sample competes with the limited binding sites in added anti-GAT antibody.Horseradish peroxidase(HRP)conjugated to goat anti-rabbit IgG was used as the enzymatic label.A carbon fiber working electrode was constructed and current signals were detected by using hydrogen peroxide as a substrate and hydroquinone as an electrochemical mediator.The electrochemical immunoassay was evaluated by analysis of GAT in buffer or swine urine and an average value of half inhibition concentration(IC50)of 8.9 ng/ml was obtained.Excellent specificity of the antibody was achieved with little cross-reaction with lomefloxacin(3.0%),ciprofloxacin(3.0%),and ofloxacin(1.9%)among commonly used(fluoro)quinolones.In conclusion,the immunoassay system developed in this research can be used as a rapid,powerful and on-site analytical tool to detect GAT residue in foods and food products.
基金Project supported by the National Natural Science Foundation of China (No. 20633010).
文摘At a weight ratio of n-C5H11OH/H2O=50/50, when the total content of sodium dodecyl sulfate (SDS) was less than 6.0%, the ternary mixture of SDS/n-C5H11OH/H2O coexisted in two immiscible microemulsions. The distribution and transfer of gatifloxacin (GTFX) between the two phases were studied using UV-Vis and electrochemistry AC impedance spectra. The results show that GTFX transferred from the upper phase (W/O) to the lower phase (O/W or bicontinuous microemulsion), but a small amount of SDS transferred from the lower phase to the upper phase correspondingly with the increase of the total SDS content at a total GTFX concentration of 1.0×10^-5 mol/L. The addition of GTFX did not change the structures of the two different phases fundamentally, but resulted in the transfer and redistribution of GTFX and SDS, so the electric properties of the system were changed correspondingly.
基金Project supported by the Natural Science Young Scholars Foundation of Chongqing University, the National Natural Science Foundation of China (No. 20331010) and Chongqing University Postgraduates' Science and Innovation Fund.
文摘Three novel isostructural complexes M(gatx)2(H2O)2·4H2O [gatx=gatifloxacin, M = Zn (1), Ni (2) and Co (3)] were synthesized at room temperature and structurally characterized by elemental analysis, IR and single crystal X-ray diffraction, which exhibit a similar mononuclear structure, in which the metal ion is coordinated by two gatifloxacin and two aqua ligands to furnish a distorted octahedral geometry, and show different activities against staphylococcus due to the different metal ions in the structures.
基金Supported by the National Natural Science Foundation of China(No.21207047), the State Major Project for Science and Technology Development, China(No.2013YQ47078102-3), the Science-Technology Development Project of Jilin Province of China(Nos.20130206014GX, 20140623007TC, 20150204017YY), the Open Project of the State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin University, China(No.2014-07) and the Natural Science Foundation of Jilin Province, China(No.20160101314JC).
文摘A novel high selective and sensitive fluorescence probe termed gatifloxacin was discovered based on fluorescence "on-off" phenomenon in the presence of Se(IV). In the Tris-HCl/acetonitrile(3:7, volume ratio, Tris-HCl 0.05 mol/L, pH=7.3) system, the fluorescence intensity of gatifloxacin was linearly decreased with the concentration increase of Se(IV) in a range of 1.0×10-5--5.0×10-5 mol/L with a correlation coefficient of 0.9979(R2=0.9958) and in a range of 5.0×10-5--1.0 ×10-4 mol/L with a correlation coefficient of 0.9973(R2=0.9946). The detection limit of Se(IV) was 1.70×10-6mol/L.
基金supported by the National Basic Research Program of China (Grant No. 2006CB403302)National Natural Science Foundation of China (Grant No. 20777010)the Program for Changjiang Scholars and Innovative Research Team in University of China (Grant No.IRT0813)
文摘Fluoroquinolone antibiotics (FQs) are frequently detected as emerging pollutants in aqueous environments.In this study,kinetics,influencing factors and mechanisms on the photodegradation of gatifloxacin,a representative FQ,were investigated.The photodegradation follows the pseudo-first-order kinetics.Gatifloxacin photodegrades with a quantum yield of (5.94 ± 0.95) × 10 3 in pure water and undergoes direct photolysis as well as self-sensitized photodegradation.The FQ photodegrades slower in freshwater and seawater than in pure water,which is attributed to the integrative effects of pH and the aqueous dissolved matter (e.g.,humic acids and NO 3-) on the photodegradation.A toxicity test using Vibrio fischeri revealed the formation of hazardous photoproducts.
基金supported by the National Natural Science Foundation of China (21173252)
文摘The reactions between gatifloxacin(GFX) and various one-electron oxidants,such as ˙OH,N3˙,Br2˙ˉ,and SO4˙ˉ,have been studied by pulse radiolysis techniques.The GFX radical anion formed in the reaction of GFX with eaqˉ could either be protonated or deprotonated,and the absorption of GFX radical anion was located at 390 nm.The transient species produced by the reaction of GFX with ˙OH radical shows a broad band in the 380?600 nm region with a shoulder,while the oxidation by N3˙,SO4˙ˉ,and Br2˙ˉ results in an absorption band with λmax = 370 nm.At neutral condition(pH 7),the rate constants of GFX reacting with ˙OH,N3˙,Br2˙ˉ,SO4˙ˉ and eaqˉ are estimated to be 1.0 × 1010,3.1 × 109,2.8 × 109,3.0 × 109,and 1.8 × 1010 dm3 mol?1 s?1,respectively.From the pH dependence on the formation of electron adducts and on the rate constant of GFX with eaqˉ,the pKa of GFX radical anion is estimated to be 5.5 and 9.3.