Simultaneous extraction of enrofloxacin and ciprofloxacin from chicken tissue by molecularly imprinted matrix solid-phase dispersion

An ofloxacin molecularly imprinted polymer was synthesized and used as a dispersant of matrix solid-phase dispersion for the determination of enrofloxacin and ciprofloxacin in chicken tissue. The selected dispersant shows high affinity to enrofloxacin and ciprofloxacin in aqueous environment and could selectively enrich them from chicken tissue matrix. The extract was sufficiently clean for further chromatographic analysis without interferences from template leakage or chicken tissue matrix. Linearity ranged from 0.03 to 200 μg/g with the correlation coefficient r² > 0.9993. The recoveries of spiked chicken tissues were in the range of 82.7–96.6% for enrofloxacin and 88.7–102% for ciprofloxacin.     

Toxicity of Senecio vernalis to laying hens and evaluation of residues in eggs

Diets with 0.0, 0.5,2.0, or 4.0% ground-aerIal parts of Senecio vernalis were fed to groups of 10 laying hens for 210 d. Plant alkaloid content was 0.14% with 8.57% in the basic form and 91.43% in the N-oxide form. Specific alkaloids were senecionin (66.65%), senecivernin (10.37%), seneciphylline (8.51%), integerrimine (8.44%), retrorsine (3.03%), senkirkine (2.35%) and hydroxysenkirkine (0.65%). At the end of the feeding period, no mortality or clinical signs occurred in any test group. However, decreases in egg production, feed efficiency, feed intake and body weight occurred on diets containing 2 or 4% of the plant. Serum gamma-GT was significantly elevated and serum albumin and protein were significantly decreased in hens fed the 2 and 4% diets. Total bilirubin was significantly higher in the 4% group. No free pyrrolizidine alkaloids were detected in eggs indicating that at these rates of dietary exposure, they did not produce residues at the level of detection or that they were bound irreversibly to egg proteins. Hens fed 2 or 4% plant diets had mild to moderate chronic liver changes of periportal or septal fibrosis, megalocytosis, bile duct hyperplasia and early regenerative nodule formation.     

Effects of inducers of cytochrome P450s on enrofloxacin N-deethylation in crucian carp Carassius auratus gibelio

In this study with crucian carp (Carassius auratus gibelio), the effect on enrofloxacin (EF) and its metabolite ciprofloxacin (CF) and on the activity of cytochrome P450 1A (CYP1A) and cytochrome P450 3A (CYP3A) was estimated following the oral administration of rifampicin (RIF) (12 mg/kg) and β-naphthoflavone (BNF) (12 mg/kg), respectively. First, reversed-phase high-performance liquid chromatography (RP-HPLC) was used to detect the pharmacokinetics of EF with continual blood sampling. In RIF-treated, BNF-treated and control groups, the value of the C_maxCF/C_maxEF ratio was 4.41, 0.81 and 0.95, and the corresponding value of the AUC_0-t-CF/AUC_0-t-EF ratio was 3.69, 1.84 and 1.76, respectively. In the RIF-treated, BNF-treated and control groups, the MRT values of EF were 26.57, 27.45 and 30.88 h, and the corresponding values for CF were 5.79, 35.18 and 38.11 h, respectively. Based on these results for crucian carp, the accumulation and elimination of EF and CF in the RIF-treated group were more rapid than in BNF-treated and control groups. Second, liver microsomes were pretreated with the inducer of CYP1A for BNF and that of CYP3A for RIF, and then the enzymatic activities of CYP1A and CYP3A were measured, respectively. The activities of ethoxyresorufin-O-deethylation (EROD) and erythromycin-N-demethylation (ERND) increased significantly (P < 0.05) for CYP1A and CYP3A, respectively. However, in further experiments on the formation of CF, the level of EF N-deethylation was significantly induced by RIF and inhibited by ketoconazole (KTZ) for CYP3A but had no influence for CYP1A, BNF and berberine chloride (BER). We concluded that CYP3A might be responsible for the N-deethylation of EF and because of this activity, could also serve as a toxicity biomarker in crucian carp.     

荧光法快速测定鸡血清中环丙沙星的残留量

目的建立快速测定鸡血清中环丙沙星(Cpfx)残留量的方法。方法采用荧光光度法。结果用甲醇沉淀蛋白对血清进行预处理,利用Cpfx-Al3 -CTMAB体系,鸡血清中Cpfx浓度在1.00~3.00μg.ml-1范围时,荧光强度与浓度呈线性关系,其回归方程为:F=37.6201 14.1576C(r=0.9991),平均回收率为100.4%,RSD=0.22%。结论所用方法简便、准确、快速,可用于鸡血清中环丙沙星的测定。     

Aflatoxin deposition and clearance in the eggs of laying hens

Hens fed a diet containing 3310 μg of AFB₁ and 1680 μg of AFB₂ per kg feed for 28 days showed a significant decrease in egg production and egg weights by wk 3 and 4 of feeding, respectively. Transfer of aflatoxins to the eggs occurred rapidly, reaching maximum levels after 4–5 days, and remained relatively constant throughout aflatoxin feeding. The mean values for combined residue levels in eggs were less than 0.5 μg/kg. Levels of AFB₂, AFM₁ and AFM₂ were similar in yolk and albumen while levels of B₁ and B_2a were higher in the yolk. Upon removal of the aflatoxin-containing diet, residues in eggs decreased rapidly. Clearance of aflatoxin residues from the albumen occurred faster than from the yolk. Thus, no residues were detected in the albumen and in the yolk after 5 and 7 days of withdrawal, respectively. No aflatoxin residues could be recovered from whole eggs after feeding the aflatoxin-free diet for 4 days.     

鸡蛋中抗菌药物残留消除规律研究进展

抗菌药在预防和治疗家禽疾病、减少饲料消耗、提高经济效益方面发挥着重要作用,但抗菌药的不合理使用导致禽类产品(尤其是鸡蛋)中出现残留,对我国养殖业的发展以及人类健康带来了重大风险和安全隐患。本文通过对国内外相关文献、资料、数据进行查阅和整理,对比分析了7大类抗菌药(包括磺胺类、喹诺酮类、四环素类、酰胺醇类、β-内酰胺类、大环内酯类、氨基糖苷类)在鸡蛋中的残留规律,为避免鸡蛋药物残留、促进蛋鸡养殖业发展、保证鸡蛋食用安全性、保障人体健康提供科学参考。     

鸡蛋中抗菌药物残留消除规律研究进展

Antimicrobial agents play an important role in preventing and treating poultry diseases, reducing feed consumption and improving economic benefits of poultry breeding industry. However, due to the unreasonable use of antimicrobial agents, the antimicrobial residues in poultry products (especially eggs) have brought great risks and safety risks to the development of China’s livestock industry and human health. Through consulting and sorting out the relevant literature data in the published papers, the residue elimination of seven kinds of antimicrobial agents (including sulfonamides, quinolones, tetracyclines, amido alcohols, β-lactams, macrolides and aminoglycosides) in eggs were compared and analyzed in order to avoid residues of antimicrobial agents in eggs and ensure the safety of eggs. Our review will provide scientific reference for promoting the development of poultry breeding industry and protecting human     

Application of terbium sensitized fluorescence for the determination of fluoroquinolone antibiotics pefloxacin, ciprofloxacin and norfloxacin in serum

A simple, rapid and sensitive spectrofluorimetric method for the determination of fluoroquinolone antibiotics, norfloxacin (NOR), ciprofloxacin (CIP) and pefloxacin (PEF) is described. The method is based on the radiative energy transfer from fluoroquinolones to terbium ions (Tb³⁺) in the presence of tri-n-octylphosphine oxide (TOPO) in weakly acidic (pH 5.5) micellar solution of cetylpyridinium chloride (CPCI). Optimum conditions for the formation of the fluoroquinolone-Tb³⁺-TOPO ternary complexes have been investigated. Under optimized conditions the detection limits are 1.7, 1.2 and 4.4 nM for NOR, CIP and PEF, respectively, while the range of application for all three drugs is 0.05–10 μM. The method has been successfully applied to the determination of NOR, CIP and PEF in serum samples after deproteinization with acetonitrile (serum-acetonitrile; 1:2, v/v). The mean recoveries from serum samples spiked with NOR, CIP and PEF (5.0–50.0 μM) were (90.3 ± 4.9), (105.0 ± 3.6) and (95.3 ± 1.5)%, respectively. Within-run and day-to-day s_r values for 5.0, 25.0 and 50.0 μM of each fluoroquinolone varied from 1.7 to 5.4% and from 3.3 to 12.8%, respectively. The influence of several usually coadministered drugs on the determination of fluoroquinolones in serum has been investigated.     

LC determination of enrofloxacin

A simple, rapid and sensitive high-performance liquid chromatographic (HPLC) method was developed for the assay of enrofloxacin in raw material and injection. The validation method yielded good results and included the range, linearity, precision, accuracy, specificity, recovery, limit of detection (LOD) and limit quantification (LOQ) values. The HPLC separation was carried out by reversed phase chromatography on a C-18 absorbosphere column (150×4.6 mm i.d. 5 μm particle size) with a phase composed of sodium acetate (pH 4.7; 0.1 M): acetonitrile (60:40, v/v; pH 5.0), pumped isocratically at a flow rate of 1.5 ml min⁻¹. The effluent was monitored at 278 nm with the eluting solvent. The calibration graph for enrofloxacin was linear from 10.0 to 80.0 μg ml⁻¹.     

Study of danofloxacin depletion in eggs of laying hens after oral administration

Danofloxacin was administered to 15 laying hens via drinking water for 12 days. Egg white and yolk from each egg were separated and danofloxacin residues were analysed by a high performance liquid chromatography method with fluorescence detection. Danofloxacin was detectable on the first day in egg white and on the second day in egg yolk after the beginning of administration, and higher danofloxacin residues accumulated in egg yolk than in egg white. Danofloxacin in egg white decreased fairly rapidly and was detectable up to 4 days after withdrawal of the drug. In egg yolk the residues declined slowly and were detectable up to 11 days after withdrawal of the drug.     

大鼠血浆中环丙沙星的HPLC荧光分析检测法及其体内药物动力学研究

建立测定大鼠血浆中环丙沙星的RP HPLC荧光检测法和研究其体内的药物动力学。以格帕沙星为内标 ,血浆样品经乙腈沉淀蛋白 ,取上清夜进行HPLC检测。流动相为 0 0 5mol/L磷酸盐缓冲液( pH3 0 )—乙腈—甲醇 ( 77∶13∶10 ,v/v/v) ,荧光检测 ,λEX=2 76nm ,λEM=448nm。血浆样品在 0 0 0 2 5～ 0 5μg/ml范围内线性关系良好 ,平均提取回收率为 97 1% ,日间和日内精密度RSD均小于 8 0 % ,最低检测限达到 1 0ng/ml。环丙沙星在大鼠体内的过程符合双隔室开放型一级吸收动力学模型、药动学参数分别为 :T1/2(ka) =0 44h ,T1/2 (α) =0 92h ,T1/2 ( β) =5 6 6h ,Tmax=1 0 4h ,Cmax=0 35 μg/ml,AUC =1 86h·μg/ml。     

Physicochemical properties of enrofloxacin

The physicochemical properties of enrofloxacin, a fluoroquinolone that inhibits the activity of bacterial DNA gyrase, are described. Its spectral, solubility and related physicochemical characteristics are discussed. The dissociation behaviour of enrofloxacin was examined by UV spectrophotometry at 25°C in a series of buffers ranging from pH 1 to 10. The corresponding macro- and microscopic dissociation constants were calculated. The apparent n-octanol-water partition coefficients were measured from pH 2 to 10.     

Influence of the cell wall on ciprofloxacin susceptibility in selected wild-type Gram-negative and Gram-positive bacteria

The susceptibility of several wild-type bacteria to ciprofloxacin and accumulation of the drug in these bacteria were evaluated. Species studied included Escherichia coli, Serratia marcescens, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis and Bacillus cereus. Ciprofloxacin susceptibility was measured for each strain using two different methods: the minimal inhibitory concentration and the bactericidal index. Significant differences were observed between the results derived from these two methods. Whereas the minimal inhibitory concentration was low in all strains tested, ciprofloxacin’s bactericidal activity, as indicated by the bactericidal index, varied with the species studied. To determine whether this finding was due to variations in cell envelope permeability to ciprofloxacin (i.e. to combined cell uptake and efflux), we studied ciprofloxacin accumulation using spectrofluorometry. In Gram-negative bacteria, differences in permeability can lead to altered susceptibility to antibiotics. In fact, the combination of slow uptake and efficient efflux seems to be crucial to the characteristic poor susceptibility of P. aeruginosa to ciprofloxacin. However, the low level of activity of ciprofloxacin against S. aureus and two Bacillus species may have resulted from the drug’s interaction with its target enzymes (i.e. topoisomerase IV in S. aureus and DNA gyrase in Bacillus spp.) rather than diminished permeability.     

A reverse-phase HPLC assay for the simultaneous determination of enrofloxacin and ciprofloxacin in pig faeces

A reverse-phase HPLC assay is described for the simultaneous assay of enrofloxacin (ENR) and ciprofloxacin (CPX) in pig faeces. Extraction used dichloromethane, 2-propanol and 0.3M ortho-phosphoric acid (1:5:4 v/v/v). Separation was achieved using a Spherisorb S5 C8 column, heated to 50 degrees C and a mobile phase of 0.16% ortho-phosphoric acid (adjusted to pH 3.0 with tetrabutylammonium hydroxide solution) with 20 ml acetonitrile per litre solution. The method used fluorescence detection (Ex 310 nm; Em 445 nm), a flow rate of 1 ml/min and a 20 microl injection volume. Retention times were approximately 6 min for ciprofloxacin and 10 min for enrofloxacin. The linearity range for both compounds was 0-20 mg/kg, lowest limit of quantification 0.3 mg/kg and recoveries were >92%.     

盐酸环丙沙星栓剂的处方改进及质量控制

目的改进盐酸环丙沙星栓的处方并建立其质量控制方法。方法采用热熔法制备栓剂,采用高效液相色谱法测定环丙沙星的含量。结果以醋酸缓冲液制备的盐酸环丙沙星栓处方较好,含量合格。结论改进的处方及制备工艺合理,质量控制方法简单、快速、准确。     

Effects of aflatoxin B1 on tissue residues of enrofloxacin and its metabolite ciprofloxacin in broiler chickens

The impact of subchronic exposure of aflatoxin B1 on the tissue residues of enrofloxacin and its metabolite ciprofloxacin was examined in broiler chickens. Broiler chickens given either normal or aflatoxin B1 (750 μg/kg diet) supplemented diets for 6 weeks received enrofloxacin (10 mg/kg/day, p.o.) for 4 days and thereafter, residue levels were determined. Aflatoxin B1 induced alterations in serum marker enzymes. As compared to unexposed broiler chickens, enrofloxacin concentrations in aflatoxin B1-exposed broiler chickens were significantly higher in all tissues (0.62-4.53 μg/g) analyzed except muscle 24h after termination of enrofloxacin administration. Ciprofloxacin was detectable in tissues of only mycotoxin-exposed broiler chickens. Enrofloxacin residues in liver, kidney and skin plus fat persisted for 10 days in mycotoxin-exposed broiler chickens whereas it was detectable only in liver of unexposed broiler chickens. Our results indicate that subchronic aflatoxin B1 exposure markedly influences the residue levels of enrofloxacin and ciprofloxacin in tissues of broiler chickens.     

Preparation and characterization of enrofloxacin/carbopol complex in aqueous solution

Since the bitter taste of enrofloxacin apparently limit the patient compliance in the oral formulations of the antibacterial agent, the masking of the taste is essential for the improvement of the therapeutic effectiveness. Therefore, this study was carried out to examine the feasibility of taste masking of enrofloxacin by the retardation of its dissolution rate using the formation of complex between the drug and Carbopol. The complexation between Carbopol and enrofloxacin was confirmed by turbidity, UV spectrophotometry, wide angle X-ray diffraction, and differential scanning calorimetry. The enrofloxacin content in the complexes was 34% (Carbo-enrofloxacin complex I) and 57% (Carbo-enrofloxacin complex II) depending on the preparation method. The dissolution rate of enrofloxacin from the complex increased as the pH was reduced. The dissolution rate of enrofloxacin from the Carbo-enrofloxacin complex I was significantly lower than that of the enrofloxacin powder. Therefore, these observations suggest that Carbo-enrofloxacin complex I can be used to mask the taste of enrofloxacin.     

硫酸镁在恩诺沙星注射液无菌检查中的应用#br#

目的 探讨恩诺沙星注射液无菌检查的方法。方法 参照《中国兽药典》2015版第一部附录1101无菌检查方法,采用薄膜过滤法,样品过滤后使用含不同浓度硫酸镁溶液的缓冲液冲洗,随后加入含不同浓度硫酸镁的培养基,根据硫酸镁的浓度设置4组试验对恩诺沙星注射液进行无菌检查。结果 按薄膜过滤法,样品过滤后使用0.1%无菌蛋白胨水溶液(含0.1mol/L MgSO4)冲洗4次,每次100mL,冲洗后向集菌器中加入100mL培养基(含0.05mol/L MgSO4),可消除恩诺沙星注射液的抑菌活性,试验菌均可正常生长。结论 该方法可用于恩诺沙星注射液的无菌检查。     

硫酸镁在恩诺沙星注射液无菌检查中的应用#br#

目的 探讨恩诺沙星注射液无菌检查的方法。方法 参照《中国兽药典》2015版第一部附录1101无菌检查方法,采用薄膜过滤法,样品过滤后使用含不同浓度硫酸镁溶液的缓冲液冲洗,随后加入含不同浓度硫酸镁的培养基,根据硫酸镁的浓度设置4组试验对恩诺沙星注射液进行无菌检查。结果 按薄膜过滤法,样品过滤后使用0.1%无菌蛋白胨水溶液(含0.1mol/L MgSO4)冲洗4次,每次100mL,冲洗后向集菌器中加入100mL培养基(含0.05mol/L MgSO4),可消除恩诺沙星注射液的抑菌活性,试验菌均可正常生长。结论 该方法可用于恩诺沙星注射液的无菌检查。     

Effects of some quinolone antibiotics on malondialdehyde levels and catalase activity in chicks

In this study, the effects of enrofloxacin, ciprofloxacin and norfloxacin at therapeutic doses and over therapeutic periods on plasma malondialdehyde (MDA) levels and erythrocyte catalase (CAT) activity were investigated. For this purpose, a hundred and sixty 3-day-old female Ross breed broiler chicks were used. Four groups, each comprising 40 were established. While group 1 was maintained as control, groups 2, 3 and 4 were administered enrofloxacin, ciprofloxacin and norfloxacin, respectively, at 10 mg/kg bw/day in drinking water. On days 1, 3, 5 and 7, ten animals were killed from each group, and plasma MDA levels and erythrocyte CAT activity were measured spectrophotometrically. The data obtained demonstrated that CAT activity was statistically decreased in groups 2 and 4, and increased in group 3 on day 1. In conclusion, it was determined that neither of the three drugs generated free radicals, in other words, caused lipid peroxidation physiologically when given at therapeutic dosage.