Gatifloxacin Research Articles

Bromatomatric assay of gatifloxacin in pharmaceuticals

Three new, simple, and cost-effective visible spectrophotometric methods are proposed for determination of gatifloxacin (GTF) using bromate-bromide mixture, and three dyes, methyl orange, indigocarmine and thymol blue, as reagents. The methods engross the addition of a known excess of bromate-bromide mixture to GTF in hydrochloric acid medium followed by determination of residual bromine by reacting with a fixed amount of either methyl orange and measuring the absorbance at 520 nm (method A) or indigo carmine and measuring the absorbance at 610 nm (method B) or thymol blue and measuring the absorbance at 550 nm (method C). In all the methods, the amount of bromine reacted corresponds to the amount of GTF, and the absorbance is found to increase linearly with the concentration of GTF. Under the optimum conditions, GTF could be assayed in the concentration range 0.25-1.5, 0.5-6.0, and 0.5-10 mg/mL by method A, method B and method C, respectively. The apparent molar absorptivities are calculated to be 1.6x105, 4.0x104 and 3.2x104 L mol-1 cm-1 for the method A, method B and method C, respectively, and the corresponding Sandell sensitivity values are 0.0025, 0.010 and 0.012 ?g/cm2. The intra-day and inter-day precision, and the accuracy of the methods were evaluated as per the current ICH guidelines. The methods were successfully applied to the determination of GTF in pharmaceutical preparations without the interference from any of the pharmaceutical adjuvant.

Validation of a capillary zone electrophoresis method for the determination of ciprofloxacin, gatifloxacin, moxifloxacin and ofloxacin in pharmaceutical formulations

Um metodo alternativo por eletroforese capilar de zona (CZE) para determinacao de ciprofloxacina (CPFLX), gatifloxacina (GTFLX), moxifloxacina (MFLX) e ofloxacina (OFLX) foi validado. O sistema de eletrolito utilizado consistiu da mistura de 25 mmol L-1 de TRIS/ HCl e 15 mmol L-1 de tetraborato de sodio em meio aquoso resultando em pH 8,87. A analise foi realizada sob deteccao direta por UV em 282 nm com tempo de analise de 3 min. Os parâmetros analiticos de validacao avaliados foram: linearidade (r > 0,998), seletividade (comparacao entre a inclinacao da curva de calibracao de padronizacao externa e curva de calibracao de adicao de padrao), repetitividade em area para amostras (RSD %: < 3,94% para CPFLX, < 3,87% para GTFLX, 1,30% para MFLX e < 1,88% para OFLX), precisao intermediaria em area para amostras (RSD%: < 3,59% para CPFLX, < 3,09% para GTFLX, 2,67% para MFLX e < 2,25% para OFLX), exatidao (media da faixa de recuperacao: 101,2% para CPFLX, 101,0% para GTFLX, 101,3% para MFLX e 99,9% para OFLX), limite de deteccao (mg L-1: 2,72 para CPFLX, 1,92 para GTFLX, 0,795 para MFLX e 1,05 para OFLX), limite de quantificacao (mg L-1: 9,06 para CPFLX, 6,40 para GTFLX, 2,65 para MFLX e 3,50 para OFLX) e robustez. Devido a simplicidade, seletividade, precisao, exatidao e rapidez, o metodo pode ser uma alternativa interessante para auxiliar o controle da qualidade dessas drogas na industria farmaceutica.

Rapid determination of gatifloxacin in biological samples and pharmaceutical products using europium‐sensitized fluorescence spectrophotometry

A europium-sensitized fluorescence spectrophotometry method using an anionic surfactant, sodium dodecyl benzene sulphonate (SDBS), was developed for the determination of gatifloxacin (GFLX). The GFLX-Eu3+-SDBS system was studied and it was found that SDBS significantly enhanced the fluorescence intensity of the GFLX-Eu3+ complex (about 25-fold). The optimal experimental conditions were determined as follows: excitation and emission wavelengths of 338 and 617 nm, pH 7.5, 3.0 x 10(-6) mol/L europium(III), and 5.0 x 10(-5) mol/L SDBS. The enhanced fluorescence intensity of the system (DeltaI(f)) showed a good linear relationship with the concentration of GFLX over the range 1.0 x 10(-8)-8.0 x 10(-7) mol/L with a correlation coefficient of 0.9990. The detection limit (S:N = 3) was determined as 1.0 x 10(-9) mol/L. This method has been successfully applied for the determination of GFLX in pharmaceuticals and human urine/serum samples. Compared with most other methods reported, the rapid and simple procedure proposed here offered higher sensitivity, wider linear range and good stability. The luminescence mechanism of the system is also discussed in detail.

Clinical efficacies of gatifloxacin (GFLX) for acute rhinosinusitis

Clinical efficacies of gatifloxacin (GFLX) for acute rhinosinusitis

Distribution and Transfer of Gatifloxacin Between Two Microemulsion Phases with Different Structures in SDS/n‐C5H11OH/H2O System

AbstractAt 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.

The inhibitory effects of fluoroquinolones on l-carnitine transport in placental cell line BeWo

l-Carnitine plays an important role in lipid metabolism by facilitating the transport of long-chain fatty acids across the mitochondrial inner membrane followed by fatty acid beta-oxidation. It is known that members of the OCTN family play an important role in l-carnitine transport in the placenta. Investigation of drug–drug or drug–nutrient interaction in the placenta is important for establishment of safety drug medication during pregnancy. The aim of this study was to determine the effects of fluoroquinolones, inhibitors of OCTN2, on l-carnitine transport in the placenta which is known to have a high expression level of OCTN2. We investigated the inhibitory effect of five fluoroquinolones, ciprofloxacin (CPFX), gatifloxacin (GFLX), ofloxacin (OFLX), levofloxacin (LVFX) and grepafloxacin (GPFX), on l-carnitine transport mediated by OCTN2 in placental cell line BeWo cells. We found that all of the fluoroquinolones inhibited l-carnitine transport, GPFX being the strongest inhibitor. We also found that the inhibitory effects of LVFX and GPFX depended on their existence ratio of zwitterionic forms as, we reported previously. Furthermore, we elucidated the LVFX transport mechanism in BeWo cells. LVFX was transported actively by transporters. However, we found that LVFX transport was Na +-independent and l-carnitine had no inhibitory effect on LVFX transport, suggesting that LVFX acts as inhibitor of OCTN2, not as a substrate for OCTN2.

Validated Polarographic Methods for the Determination of Certain Antibacterial Drugs

Two simple, precise, inexpensive and sensitive voltammetric methods for the determination of lomefloxacin (LFX), sparfloxacin hydrochloride (SFX), gatifloxacin (GFX), and moxifloxacin (MFX) were developed. The present methods were first used to explore the adsorption behavior of the four investigated antibacterial agents at a hanging mercury dropping electrode (HMDE), by a direct method and secondly by a modification via their complexation with PdCl(2). For the direct method, drugs were accumulated on HMDE, and a well-defined reduction peak was obtained in Britton-Robinson buffer of pH 7 for LFX and SFX, and pH 6 for GFX and MFX. The adsorptive stripping response was evaluated as a function of some variables such as the scan rate, pH, accumulation time and potential. For the modified method, the adsorptive behavior of Pd(II)-4-quinolone complexes at the HMDE developed a strippining voltammetry peak at a more negative potential than that of the free Pd(II) ions (-1.05 V). The limits of detection (LOD) were 2 x 10(-8) M, while the limits of quantification (LOQ) were 6 x 10(-8) M for the investigated drugs. The methods were applied to the determination of LFX, SFX, GFX, and MFX in biological samples and pharmaceutical preparations, and also compared with the official reference methods. Complete validation of the proposed methods was also done.

Atomic absorption spectroscopic, conductometric and colorimetric methods for determination of some fluoroquinolone antibacterials using ammonium reineckate

Three accurate, rapid and simple atomic absorption spectrometric (AAS), conductometric and colorimetric methods were developed for the determination of gatifloxacin (GTF), moxifloxacin (MXF) and sparfloxacin (SPF). The proposed methods depend upon the reaction of ammonium reineckate with the studied drugs to form stable precipitate of ion-pair complexes, which was dissolved in acetone. The pink coloured complexes were determined either by AAS or colorimetrically at λ max 525 nm directly using the dissolved complex. Using conductometric titration, the studied drugs could be evaluated in 50% (v/v) acetone. The optimizations of various experimental conditions were described. Optimum concentration ranges for the determination of GTF, MXF and SPF were 5.0–150, 40–440 μg mL −1 and 0.10–1.5 mg mL −1 using atomic absorption (AAS), conductometric and colorimetric methods, respectively. Detection and quantification limits are ranges from 1.5 to 2.3 μg mL −1 using AAS method or 30–45 μg mL −1 using colorimetric method. The proposed procedures have been applied successfully to the analysis of these drugs in pharmaceutical formulations and the results are favourably comparable to the reference methods.

Fluorescence probe enhanced spectrofluorimetric method for the determination of gatifloxacin in pharmaceutical formulations and biological fluids

A spectrofluorimetry for the determination of gatifloxacin (GFLX) was developed based on the strong fluorescence of gatifloxacin after adding fluorescence probe yttrium in buffer solution (pH 7.0) and various factors of influencing fluorescence have been researched. Under the optimum conditions, the liner range was 4.00 × 10 −8 to 1.00 × 10 −6 g mL −1 and the detection limit is 3.36 × 10 −9 g mL −1 (correlation coefficient r = 0.9997), respectively. The relative standard deviation was 1.1% for 11 measurements of 5.6 × 10 −7 g mL −1 gatifloxacin standard solution. The mechanism of sensitizing effect of probe was discussed. The proposed method has been successfully applied to determine real samples and the obtained results are in good agreement with the results of HPLC.

Voltammetric behavior of some fluorinated quinolone antibacterial agents and their differential pulse voltammetric determination in drug formulations and urine samples using a β-cyclodextrin-modified carbon-paste electrode

A voltammetric determination of ofloxacin (OF), norfloxacin (NF), gatifloxacin (GF), and lomefloxacin (LF) at a β-cyclodextrin-modified carbon-paste electrode (CDMCPE) is described. A large increase in the peak currents was observed in cyclic voltammetry (CV) and differential pulse voltammetry (DPV) of OF, NF, GF, and LF at CDMCPE compared with a bare carbon-paste electrode (CPE). These increases in the peak currents were attributed to the complex formation of the quinone group of the drugs with β-cyclodextrin. CV studies indicate that the process is irreversible and adsorption-controlled. The experimental parameters which influence the peak current responses of OF, NF, GF, and LF were studied. The reduction peak currents of OF, NF, GF, and LF change linearly over the common concentration range from 3.2 × 10−8 to 2 × 10−5 M, with a common correlation coefficient and limit of detection of 0.9995 and 2.4 × 10−8 M, respectively, in pH 4.0 Britton-Robinson (BR) buffer at an accumulation time of 160 s. The interference of metal ions in the peak current response was also studied. The modified electrode exhibited good sensitivity and stability. The proposed method was applied to the determination of OF, NF, GF, and LF in both commercially available drugs and spiked human urine samples.

Oral gatifloxacin in the outpatient treatment of children with cancer fever and neutropenia

Fever in neutropenic (FN) patients requires immediate broad-spectrum antibiotics, however, such patients do not represent a homogeneous population and the majority of them are at low risk of developing complication. Gatifloxacin (GA) is an alternative, though it has not been thoroughly studied in Pediatrics yet. The aim of this study was to evaluate oral GA in oncology pediatric patients with FN and low risk of infectious complications. We conducted a prospective study in patients submitted to chemotherapy and FN, from the ages of 3 to 21 years old, with solid tumors, acute lymphoid leukemia, and lymphomas without comorbidities and treated as outpatient with oral GA. Safety and adverse effects were monitored. We evaluated 108 patients with 201 episodes of FN. The average age was 10.8 years, 64.8% of the patients were male. Osteosarcoma accounted for 22% of the episodes, rhabdomyosarcoma for 13%, acute lymphoid leukemia, lymphomas and Ewing sarcoma, for 11% each. Among the 174 episodes exclusively treated as outpatients, the average duration of neutropenia was 4.8 days, the average duration of fever was 2.4 days; the average duration of the treatment was 8.1 days. The treatment was successful in 75.9%, analyzing only the first episodes. No patient died during the study. Adverse events included diarrhea, vomiting, increased liver enzymes, arthralgia, and ECG changes. Oral GA is effective and safe in the management of oncology pediatric patients with FN at low risk of infectious complications in the outpatient setting.

Gatifloxacin Biodegradable Implant for Treatment of Experimental Osteomyelitis: In Vitro and In Vivo Evaluation

Osteomyelitis is an inflammatory bone disease caused by pyogenic bacteria. The advantages of localized biodegradable therapy for osteomyelitis include high local antibiotic concentration at the site of infection and obviation of the need for removal of the implant after treatment. The purpose of this study was to develop and evaluate a biodegradable implantable delivery system containing gatifloxacin (GAT) for the localized treatment of osteomyelitis, experimentally induced by methicillin resistant Staphylococcus aureus (MRSA). Implants, prepared by solvent casting technique, showed reasonable tensile strength. DSC examination indicated that GAT is present in an amorphous form in the implant. The in vitro release of GAT showed a profile characterized by an initial burst followed by a second stage of gradual delivery over 27 days. The in vivo release study revealed that GAT concentrations achieved during the first 3 weeks after implantation exceeded the MIC of GAT against MRSA by > 100,000 times. Bacterial tibial bone count performed in rabbits tibia 2 and 4 weeks after implantation of GAT implant in infected bone indicated complete eradication of infection in all treated rabbits as indicated by the significant decrease in bacterial count. The results show that the proposed implant may have a promising role in the therapeutic approach to osteomyelitis.

Penetration of Gatifloxacin Eye Drops into the Aqueous Humor in Humans

The authors topically administered gatifloxacin (GFLX) into the eye before cataract surgery and measured the concentrations of this agent to determine its penetration into aqueous humor. Seventy-seven patients with age-related cataracts who underwent cataract surgery were enrolled in this study. They received 0.3% GFLX ophthalmic solution 4 times at 30-min intervals, beginning 2 h before surgery. Aqueous humor was aspirated from the anterior chamber and assayed for GFLX concentration using high-performance liquid chromatography. The mean intraoperative GFLX concentration in aqueous humor was 0.485 ± 0.328 μ g/mL. GFLX level was 0.573 ± 0.367 μ g/mL in elderly patients, at least 70 years of age, and was significantly higher than that (0.322 ± 0.135 μ g/mL) in the patients less than 70 years old. This concentration was close to or higher than the minimum inhibitory concentrations required to inhibit the growth of 90% of major pathogens of endophthalmitis (MIC90), such as Staphylococcus aureus, Streptococcus pneumoniae, and Enterococcus faecalis associated with poor prognosis, other than Staphylococcus epidermidis, Pseudomonas aeruginosa, and MRSA (methicillin-resistant S. aureus) in vitro. The GFLX concentrations found in aqueous humor samples were sufficient to kill bacteria other than S. epidermidis, P. aeruginosa, and MRSA in vitro.

Gatifloxacin Induces Augmented Insulin Release and Intracellular Insulin Depletion of Pancreatic Islet Cells

Many hypoglycemic and hyperglycemic episodes associated with clinical use of gatifloxacin (GFLX), a novel fluoroquinolone antimicrobial agent, have been reported in recent years. Some have reported hypoglycemia induced by fluoroquinolones, indicating that these agents may stimulate insulin secretion from pancreatic islet cells. In this study, we investigated the effect of GFLX on insulin homeostasis in islet cells using the insulin secreting cell line, HIT-T15. After 1 h incubation with over 100 microM of GFLX, insulin secretion from the cells was significantly augmented. However, the augmentation of insulin release induced by GFLX subsequently reached a plateau. Coincidentally, cellular insulin was decreased by 120 h incubation, and reactivity to re-stimulation by sulfonylurea was suppressed. The GFLX insulin depletion effect was stronger than the effects produced by such other fluoroquinolones as levofloxacin and ciprofloxacin. This study suggests that GFLX should induce insulin oversecretion from pancreatic islet cells in the short-term, and decrease insulin productivity or increase insulin disintegration in the long-term. These results are consistent with the clinical results of GFLX finding that hypoglycemic episodes were seen after a first single administration, and most hyperglycemic episodes were seen more than 2 d after the start of administration.

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Moxifloxacin(MFLX) and garenoxacin(GRNX), new synthetic antibacterial agents, were assessed for in vitro anti-M. leprae activities. The anti-bacterial activities of these two drugs were compared to those of sparfloxacin (SPFX), gatifloxacin(GFLX), levofloxacin(LVFX) and rifampicin (RFP). The anti-M leprae activity obtained by Buddemeyer system was stronger in order of RFP, MFLX, SPFX, GFLX and GRNX and LVFX. The anti-M. leprae activity of MFLX or GRNX was also examined by the nude mouse footpad method. MFLX completely inhibited the growth of M. leprae inoculated into nude mouse footpads, when given orally at a daily dose of 10 mg/kg , while GRNX completely inhibited at a daily dose of 60 mg/kg. Both in vitro and in vivo tests indicated that MFLX was equal or superior to SPFX, but GRNX was equipotent to LVFX, in terms of anti-M. leprae activities.

Antacid interaction with new quinolones: dose regimen recommendations based on pharmacokinetic modeling of clinical data for ciprofloxacin, gatifloxacin and norfloxacin and metal cations

New quinolones (NQs) are widely used to treat various infections. However, concomitant oral administration of metal cations may decrease absorption of NQs and consequently decrease their blood concentration and pharmacological effect. A convenient approach to avoid this interaction is to separate the dosages by a certain interval. In this study, we aimed to develop a novel pharmacokinetic model to describe NQs-metal cation interactions in order to estimate the optimal dosing interval. Plasma concentration-time profiles of NQs after administration without or with metal cations at various dosing intervals were collected from the literature and analyzed with a pharmacokinetic model incorporating the formation ofNQs-metal cations complex. The model was fitted to the reported time profiles ofciprofloxacin (CPFX) plasma concentration after concomitant administration with aluminum hydroxide/magnesium hydroxide antacid (Al/Mg antacid; Maalox, Maalox70) at various dosing intervals to obtain the pharmacokinetic parameters of CPFX. Model analysis was also carried out for gatifloxacin (GFLX) and norfloxacin (NFLX). The developed model could adequately explain the interactions in all the combinations investigated. The model predicted, in the cases of usual doses of CPFX with Maalox, GFLX with Maalox70 and NFLX with sucralfate, that the NQ should be administered 4.5, 4.5 and 3.5 hours after, or 1, 1 and 0.5 hours before the administration of metal cations, respectively, to ensure 90% of control absorption. The developed model can adequately describe the extent of interaction between NQs and metal cations, and should be clinically useful to design dosage regimens to circumvent the interaction.

Sensitive Spectrophotometric Methods for the Determination of Gatifloxacin in Pharmaceuticals Using Bromate‐Bromide, Methylene Blue and Rhodamine‐B as Reagents

Two new simple, precise, rapid and extraction‐free spectrophotometric methods are proposed for the determination of gatifloxacin(GTF) using bromate‐bromide mixture and two dyes, methylene blue and rhodamine B, as reagents. Spectrophotometric methods entail the addition of a known excess of bromate‐bromide mixture to GTF in hydrochloric acid medium followed by determination of residual bromine by reacting with a fixed amount of either methylene blue and measuring the absorbance at 665 nm (Method A) or rhodamine B and measuring the absorbance at 555 nm (Method B). Beer᾽s law is obeyed in the ranges, 0.5‐5.0 and 0.2‐1.5 μg mL-1 for method A and method B, respectively. The apparent molar absorptivities are calculated to be 5.6×104 and 9.6×104 L mol-1cm-1 for method A and method B, respectively, and the corresponding Sandell sensitivity values are 0.0071 and 0.0042 μg cm-2. The methods were successfully applied to the assay of GTF in pharmaceutical formulations with satisfactory results.

Rapid Detection of Point Mutations Conferring Resistance to Fluoroquinolone in gyrA of Helicobacter pylori by Allele-Specific PCR

Helicobacter pylori strains with reduced susceptibility to fluoroquinolones have a mutation at either codon 87 Asn or 91 Asp of the gyrA gene. A rapid test based on an allele-specific PCR (AS-PCR) was designed to detect the gyrA mutations. Clinical H. pylori isolates were obtained from the stomachs of 51 patients with H. pylori infections who showed treatment failure. The MICs of gatifloxacin (GAT) were determined by the agar dilution method. Identical genotyping results were obtained with AS-PCR and conventional PCR. The gyrA mutations of H. pylori causing reduced susceptibility to fluoroquinolones could be detected successfully by this method. A significant association was observed between the presence of mutations, as detected by AS-PCR, and the resistance of the strains to GAT. Moreover, genotyping by AS-PCR took less than 3 to 4 h. The AS-PCR method for the detection of gyrA mutations in H. pylori is useful for easy identification of fluoroquinolone-resistant strains of H. pylori.

O-Carboxymethylchitosan-based novel gatifloxacin delivery system

The increase in the treatment efficacy due to the enhanced permeability and retention properties and the decrease in the minimum inhibitory concentration (MIC) are the vital challenges related to the administration of the antibiotic drugs. In the present paper, we describe a novel delivery system of gatifloxacin (GFLX) from O-carboxymethylchitosan (OCMCS). GFLX is a fourth-generation fluoroguinolone, which has shown promise with excellent activity against both Gram-positive cocci and Gram-negative bacteria both in vitro and in vivo. OCMCS is a biocompatible amphiphilic derivative of chitosan. GFLX could be entrapped into OCMCS by the interaction between OCMCS and GFLX, which was characterized by fluorescence spectrum, transmission electron microscope, and dynamic light scattering techniques. The release behaviors of GFLX from this proposed delivery system in phosphate-buffered saline (PBS) solution at 37 °C were studied by fluorescence spectroscopy. The MIC of OCMCS formulation was evaluated. The results demonstrate that the release of GFLX from OCMCS formulation is slower than that from GFLX solution. In vitro bacteria antiproliferative activity assay confirms that the MIC of OCMCS formulation against Gram-negative bacteria is fourfold lower than the system without OCMCS. However, it seems that OCMCS has insignificant effect against Gram-positive bacteria. These results suggest that OCMCS matrix has obvious “transmission effect” on Gram-negative bacteria.

The concentrations of fluoroquinolones in prevention of Staphylococcus epidermidis from mutant in ocular surface

To examine the mutant prevention concentration (MPC) of the four fluoroquinolones to Staphylococcus epidermidis from ocular in vitro, and to compare the MPCs to the minimal inhibitory concentrations (MICs). The MICs of the ciprofloxacin, ofloxacin, levofloxacin and gatifloxacin were determined by the standard twofold agar dilution methods of the National Committee for Clinical Laboratory Standards (NCCLS). The single colony of Staphylococcus epidermidis on the blood agar plate was inoculated into Muller Hinton broth. The turbidity of the actively growing broth culture was adjusted to 1 x 10(8) cfu/ml and then the broth was diluted 1:10 and 1 microl of the diluted broth was inoculated on the Muller Hinton agar surface for each drug in different concentrations. The final inoculum was approximately 10(4) cfu. The MPCs were measured by mix-bacterial methods. The concentrations of the drugs used in MPC's determination were determined according to the drug's MIC(50) to the bacteria. 1 ml of drug's broth and 19 ml suspension of the bacteria and Muller Hinton agar were added into one plate with the final 10(10) cfu of inoculum. The lowest MIC(90) was gatifloxacin at 0.25 mg/L, the medium MIC(90) is levofloxacin at 0.50 mg/L, the highest MIC(90) at 1.00 mg/L was detected in ciprofloxacin and ofloxacin. The MPC(50) and MPC(90) for gatifloxacin were 1.00 mg/L and 2.00 mg/L respectively, which were the lowest concentration among the four drugs tested. The same parameter of the MPC(50) (2.00 mg/L) and MPC(90) (4.00 mg/L) was obtained in levofloxacin and ciprofloxacin, the MPC(50) for ofloxacin was as high as levofloxacin and ciprofloxacin at 2.00 mg/L but its MPC(90) was 8.00 mg/L. The new fluoroquinolones shows high effect on anti-bacterial Staphylococcus epidermidis. Gatifloxacin and levofloxacin may play a role in prevention Staphylococcus epidermidis from mutation.