超高效液相色谱法测定水产品中3种喹诺酮类药物残留量

提出了应用超高效液相色谱法测定水产品中诺氟沙星、环丙沙星和恩诺沙星等3种喹诺酮类药物残留量的方法。样品采用酸化乙腈提取,减压蒸干后用流动相溶解,经正己烷脱脂。以ACQUITY UPLCTMBEH C18色谱柱为分离柱,以乙腈与甲酸(0.1+99.9)溶液按体积比10比90混合作为流动相,在激发波长280nm、发射波长450nm的条件下进行荧光光度检测。3种药物的线性范围均为1.25～500μg.L-1,检出限(3S/N)均为0.1μg.kg-1,测定下限(10S/N)均为0.3μg.kg-1。以鲳鱼、对虾、河蟹等空白样品为基体做加标回收试验,测得回收率均大于80%。     

Synthesis of N-aryl-2,2,2-trifluoroacetimidoyl piperazinylquinolone derivatives and their antibacterial evaluations

N-substituted trifluoroacetimidoyl chlorides were used for the synthesis of new piperazinylquinolone derivatives. These reactions provided N-aryl-2,2,2-trifluoroacetimidoyl piperazinylquinolone derivatives in good yields. Two selected compounds were evaluated for their antibacterial activities. These compounds displayed good antibacterial activities.     

刚果红分光光度法测定盐酸环丙沙星

在pH 4.39的乙酸钠-盐酸缓冲溶液中,盐酸环丙沙星与刚果红发生离子缔合反应,其最大吸收波长位于500nm处,表观摩尔吸光系数ε=9.46×104L/（mol.cm）,盐酸环丙沙星浓度在0.8—3.2mg/L范围内呈良好的线性关系,线性回归方程为A=0.3635＋0.01113C（mg/L）,相关系数r=0.9966;检出限为9ng/L;RSD为1.6%,据此建立了测定盐酸环丙沙星的新方法。优化了对盐酸环丙沙星的测定条件。本法仪器设备简单,操作简便,体系稳定,回收率测定结果较满意。     

A Rapid Total Synthesis of Ciprofloxacin Hydrochloride in Continuous Flow

Within a total residence time of 9 min, the sodium salt of ciprofloxacin was prepared from simple building blocks via a linear sequence of six chemical reactions in five flow reactors. Sequential offline acidifications and filtrations afforded ciprofloxacin and ciprofloxacin hydrochloride. The overall yield of the eight‐step sequence was 60 %. No separation of intermediates was required throughout the synthesis when a single acylation reaction was applied to remove the main byproduct, dimethylamine.     

Enzymatic rotating biosensor for ciprofloxacin determination

The high sensitivity that can be attained using an enzymatic system and mediated by catechol has been verified by on-line interfacing of a rotating biosensor and continuous flow/stopped-flow/continuous-flow processing. Horseradish peroxidase, HRP [EC 1.11.1.7], immobilized on a rotating disk, in the presence of hydrogen peroxide, catalyzed the oxidation of catechol, whose back electrochemical reduction was detected on a glassy carbon electrode surface at −200 mV. Thus, when ciprofloxacin (CF) was added to the solution, this piperazine-containing compound participate in Michael addition reactions with catechol to form the corresponding piperazine-quinone derivatives, decreasing the peak current obtained, in proportion with the increase of its concentration. The highest response for CF was obtained around pH 7. This method could be used to determine CF concentration in the range of 0.02-65 μM (r = 0.999). The determination of CF concentration was possible with a detection limit of 0.4 nM, in the processing of as many as 25 samples per hour. Application of this analysis to different pharmaceutical samples containing CF supports the utility of the HRP-rotating biosensor.     

HPLC determination of ciprofloxacin, cloxacillin, and ibuprofen drugs in human urine samples

This paper reports, for the first time, a liquid chromatographic method for the simultaneous determination of three frequently co-administered active principles, two antibiotics, ciprofloxacin (CIPRO) and cloxacillin (CLOXA) belonging to the fluoroquinolones and beta-lactam families, respectively, and ibuprofen (IBU), a non-steroidal anti-inflammatory drug. The chromatographic separation was performed on a C-18 analytical column, using isocratic elution with methanol-acetonitrile-pH 3 formate buffer (CT = 0.1 M) (15:12:73, v/v/v) for 3 min and, after that, a linear gradient with methanol-acetonitrile (88:12, v/v) for 8 min. Several absorption spectra were obtained for each peak using a DAD detector. Chromatograms at the maximum absorption wavelength for each analyte, 220 nm for both IBU and CLOXA, and 280 nm for CIPRO were selected as the most suitable. The proposed chromatographic method requires about 15 min per sample. The presence of a urine background was tested and no interference was found. The method was satisfactorily applied to the determination of CIPRO, CLOXA, and IBU, in fortified urine, and in urine samples from a patient undergoing treatment with these three active principles, among others. Limits of quantification in urine were 1.00, 1.70, and 2.87 microg/mL for CIPRO, CLOXA, and IBU, respectively.     

高效液相色谱同时测定鸡蛋中4种氟喹诺酮类药物残留

建立了固相萃取—反相高效液相色谱同时分析鸡蛋样品中4种氟喹诺酮类药物残留量的方法。对鸡蛋样品的提取及其在C18固相萃取柱上的净化条件进行了研究,采用高效液相色谱分离,荧光检测器检测(λex=280nm,λem=450nm),外标法定量。4种沙星标准曲线的线性回归系数均在0．9999以上,环丙沙星、恩诺沙星、沙拉沙星的线性范围为2．5～500μg／L;达诺沙星为0．5～100μg/L。鸡蛋样品中4种沙星的加标回收率为78．1％～95．7％;相对标准偏差为4．1％～16．2％。环丙沙星、恩诺沙星、沙拉沙星的最低检出限为10μg／kg;达诺沙星的最低检出限为2μg/kg。     

磁性伊利石表面分子印迹材料的制备及其对环丙沙星识别特性研究

利用溶剂热法制备磁性伊利石(MILT),以乙烯基功能化的磁性伊利石(MILT-MPS)为基质材料,通过表面引发原子转移自由基聚合法在甲醇/水的混合溶液中制备表面分子印迹材料(MMIPs)。通过 FT-IR、TEM、TGA、XRD 和 VSM 等方法对其物理化学性质进行了表征,其比表面积为109.58 m2/ g,且具有热稳定性、超顺磁性(Ms =3.866 emu/ g)。吸附实验研究表明,Langmuir 等温模型能较好地拟合 MMIPs 对 CIP 的吸附平衡数据,25℃时 MMIPs 的单分子层吸附容量为86.58 mg/ g。选择性识别实验表明,MMIPs 对 CIP 具有较好地选择性识别性。结合高效液相色谱分析技术,将所制备的 MMIPs 应用于环境样品中 CIP 的分离富集和分析测定,方法回收率为93.4%~98.3%,检出限达0.01 mg/ L。     

环丙沙星荷移反应及荧光光谱性质研究

研究了环丙沙星（CPFX）与电子受体2，3－二氰－5，6－二氯－1，4对苯酯（DDQ）之间的荷移反应。实验结果表明：DDQ与CPFX的荷移反应需在丙酮－甲醇（1：4）介质中进行。两者于40℃水浴中恒温30min即可形成1：1络合物，其荧光发射较CPFX有显著的增强。在0．107．2mg/L浓度范围内，荧光强度与质量浓度呈良好线性关系；其检出限为0．1mg/L。本方法用于片剂中环丙沙星的含量测定，其回收率为96．6％－100．2％；标准偏差为1．3％－2．6％。     

Differential electrolytic potentiometric titration method for the determination of ciprofloxacin in drug formulations

A simple and rapid differential electrolytic potentiometric titration method for the determination of ciprofloxacin was developed. The work is based on the fast complexation reaction between iron(III) and ciprofloxacin in a ratio of 1:3, respectively, in sulfuric acid media of 0.09 mol dm⁻³. Among the electrodes tested silver amalgam electrodes were found to be a suitable indicating system. By applying a current density of 0.5 μA cm⁻² to these electrodes and using iron(III) solution of 0.097 mol dm⁻³ as a titrant, normal titration curves were obtained. The method was successfully applied for the determination of ciprofloxacin in drug formulations as low as 4.0 ppm.