Ultrasound wave assisted removal of Ceftriaxone sodium in aqueous media with novel nano composite g-C3N4/MWCNT/Bi2WO6 based on CCD-RSM model

The aim of this study was ultrasound assisted removal of Ceftriaxone sodium (CS) based on CCD model. Using sonochemical synthesized Bi₂WO₆ implanted on graphitic carbon nitride/Multiwall carbon nanotube (g-C₃N₄/MWCNT/Bi₂WO₆). For this purpose g-C₃N₄/MWCNT/Bi₂WO₆ was synthesized and characterized using diverse approaches including XRD, FE-SEM, XPS, EDS, HRTEM, FT-IR. Then, the contribution of conventional variables including pH, CS concentration, adsorbent dosage and ultrasound contact time were studied by central composite design (CCD) under response surface methodology (RSM). ANOVA was employed to the variable factors, and the most desirable operational conditions mass provided. Drug adsorption yield of 98.85% obtained under these defined conditions. Through conducting five experiments, the proper prediction of the optimum point were examined. The respective results showed that RSD% was lower than 5% while the t-test confirmed the high quality of fitting. Langmuir isotherm equation fits the experimental data best and the removal followed pseudo-second order kinetics. The estimation of the experimentally obtained maximum adsorption capacities was 19.57 mg.g⁻ of g-C₃N₄/MWCNT/Bi₂WO₆ for CS. Boundary layer diffusion explained the mechanism of removal via intraparticle diffusion.     

GC–MS characterisation and antibacterial activity evaluation of Nigella sativa oil against diverse strains of Salmonella

Salmonella resistance is becoming a worldwide serious health issue in these days; therefore, it is an urgent need to develop some alternative approaches to overcome this problem. Twenty bacterial strains were isolated and purified from different environmental sources and confirmed as Salmonella by morphological and biochemical analyses. Further confirmation was done by 16s rRNA sequencing. Antibiotic susceptibility test was performed by well diffusion assay against different concentrations of Ceftriaxone and Ciprofloxacin. The behaviour of both antibiotics was different against diverse strains of Salmonella. Salmonella strains resistant to both antibiotics were analysed for antibacterial activity of natural extracts of Nigella sativa (black seeds). N. sativa oil was found to be more effective against Salmonella species for which even Ceftriaxone and Ciprofloxacin were ineffective. Gas chromatography and mass spectrometry analysis of N. sativa oil was also accomplished, exhibiting 10 compounds including thymoquinone, p-cymene, cis-carveol, thymol, α-phellandrene, α-pinene, β-pinene, trans-anethole, α-longipinene and longifolene.     

Spectrophotometric Determination of Certain Cephalosporins Using Ferrihydroxamate Method

Cephalexin, cefixime, ceftriaxone and cefotaxime were determined spectrophotometrically in the pure form and in pharmaceutical formulations by using ferrihydroxamate method. Reaction optimization with respect to reaction time and temperature has been investigated. Influence of the presence of ester functional group on the determination of cephalosporins as ß-lactams under conditions optimized was evaluated. Using cefotaxime sodiume as model drug with ester functional group, it was shown that proposed method gives equally acurate and precise results even in the presence of ester functional group.     

头孢曲松钠与金属离子作用的光谱研究

研究了头孢曲松钠与Cd2＋、Ce3＋、Eu3＋、Tb3＋金属离子络合体系的紫外光谱和荧光光谱特征。结果表明,头孢曲松钠与金属离子的紫外光谱均发生不同程度的蓝移,甚至吸收峰消失,其吸光度除Cd2＋的升高,其余都下降;荧光强度也有明显的变化,加入Cd2＋、Eu3＋后头孢曲松钠的荧光猝灭,而加入Tb3＋后头孢曲松钠的荧光增强。在此基础上,采用头孢曲松钠与Cd2＋、Ce3＋、Eu3＋、Tb3＋金属离子物质的量之比分别为1∶0.6、1∶1、1∶0.6、1∶3合成络合物,并且利用红外光谱和元素分析对络合物进行验证。     

多光谱技术结合分子模拟研究头孢唑林和头孢曲松与人血清白蛋白的相互作用

头孢唑林(CFZ)属第一代β-内酰胺类半合成头孢菌素,对革兰氏阳性菌和革兰氏阴性菌均有较强的抗菌作用。头孢曲松(CRO)属第三代β-内酰胺类广谱抗生素,对敏感致病菌导致的疾病及手术后期感染预防有一定作用。人血清白蛋白(HSA)作为生物体内循环系统中含量最丰富的蛋白质,可以与多种内源性和外源性化合物可逆性结合,起到储存和转运的作用。因此,研究CFZ和CRO与HSA的相互作用对了解CFZ和CRO的药代动力学行为具有重要意义。在模拟生理条件下,采用多种光谱法和分子对接技术研究CFZ和CRO与HSA的相互作用。结果表明,在298和310 K条件下,CFZ和CRO与HSA分别形成复合物导致内源荧光猝灭,猝灭机制均为静态猝灭。在消除内滤光影响下,HSA-CFZ和HSA-CRO体系的猝灭常数(K_SV)和结合常数(K_a)均随着温度的升高而降低,结合位点数约为1。根据Fster能量转移定律,CFZ和CRO与HSA结合距离分别为2.41和1.40 nm。希尔系数(n_H)值小于1,表明CFZ和CRO分别与HSA结合后存在药物间负协同作用。热力学参数(ΔH_HSA-CFZ=-22.67 kJ·mol-1, ΔH_HSA-CRO=-39.56 kJ·mol-1, ΔS_HSA-CFZ=-4.90 J·mol-1·K-1, ΔS_HSA-CRO=-37.28 J·mol-1·K-1) 揭示,CFZ和CRO能自发地通过氢键和范德华力与HSA相结合。三维荧光光谱和圆二色谱法(CD)显示CFZ和CRO使HSA的微环境和构象发生改变。分子对接技术显示CFZ和CRO均结合在HSA的site Ⅰ结合位点上,与取代实验结果一致。本研究有助于了解CFZ和CRO在机体内的作用机制及对HSA结构和功能的影响。     

Development and Validation of a High-Performance Liquid Chromatographic Determination of Ceftriaxone Sodium and Its Application to Drug Quality Control

Abstract

A reliable and sensitive RP-HPLC method was developed and validated for the quantitative estimation of ceftriaxone sodium (CFTZ) in pure drug and pharmaceutical dosage forms. The separation of ceftriaxone sodium was achieved on a Waters XTerra RP-18 (5 µm, 250 × 4.6 mm i.d.) column using photodiode array detector at 240 nm. The mobile phase consisted of 0.1 M triethylammoniumacetate–acetonitrile (60:40 v/v) mixture delivered at a flow rate of 1.0 ml/min. Accuracy, evaluated by means of the spike recovery method, was excellent, with percent recovery in the range 99.5–102% with precision in the range 0.3–1.2%.     

Simultaneous Determination of Ceftriaxone Sodium and Non Steroidal Anti‐Inflammatory Drugs in Pharmaceutical Formulations and Human Serum by RP‐HPLC

An accurate, sensitive and least time consuming reverse phase high performance liquid chromatographic (RP‐HPLC) method for the estimation of ceftriaxone in the presence of non steroidal anti‐inflammatory drugs in formulation and human serum has been developed and validated. Chromatographic separation was conducted on prepacked Purospher Star, C18 (5 μm, 250 × 4.6 mm) column at room temperature using methanol:water:acetonitrile (80:15:5 v/v/v) as a mobile phase, pH adjusted at 2.8 with ortho‐phosphoric acid and at a flow rate of 1.0 mL/minute, while UV detection was performed at 270 nm. The results obtained showed a good agreement with the declared content. The method shows good linearity in the range of 2.5‐25 μg/mL ceftriaxone serum concentrations with a correlation coefficient 0.999 (inter‐ and intra‐day RSD < 2.0%). The limit of detection and quantification for ceftriaxone and NSAID's in pharmaceutical formulation and serum were in the range 0.51‐1.54 μg/mL. Analytical recovery was >98.1%. The proposed method may be used for the quantitative analysis of commonly administered non steroidal anti‐inflammatory drugs i.e. tiaprofenic acid, naproxen sodium, flurbiprofen, diclofenac acid and mefenamic acid alone or in combination with ceftriaxone from raw materials, dosage formulations and in serum. The established HPLC method is rapid, accurate and selective, because of its sensitivity and reproducibility.     

沉淀浮选铜光度法测定头孢曲松钠

建立了沉淀浮选铜测定头孢曲松钠的新方法。研究表明:pH4.0,头孢曲松钠的降解产物中的巯基能将Cu(Ⅱ)还原成Cu(I),所生成的Cu(I)与降解产物中的巯基生成白色乳状硫化物沉淀。通过测定溶液中剩余Cu(II)的吸光度,可以间接测定头孢曲松钠的含量。线性方程:A=4.803+0.0886ρ(μg/mL),线性范围为0.60～35μg/mL,相关系数r=0.9996,表观摩尔吸光系数ε=5.1×104L·mol-1.cm-1。方法已用于测定头孢曲松钠注射剂中头孢曲松钠的含量。     

Simultaneous Electrochemical Sensing of Ceftriaxone and Piroxicam Using Zeolite Modified Electrode for Medical Applications

The simultaneous sensing of Ceftriaxone (Cef) and Piroxicam (Pir) was presented in detail through the electrochemical method in which carbon paste electrode (CPE) was modified by meso-structured Zeolite for medical application. The results indicated a polycrystalline Zeolite phase with a relatively high surface contact for charge transportation in the sensing process. Electrochemical impedance spectroscopy (EIS) plots also showed better charge transportation parameters for the modified electrode. The effect of analytes concentration, in both individual and simultaneous states, on the electrochemical sensor quality parameters was investigated by different methods and the obtained results were thoroughly discussed.     

Spectrofluorimetric study on the inclusion behavior of p-sulfonated calix arene with cetyltrimethylammonium bromide and analytical application

The characteristics of host-guest complexation between p-sulfonated calix [G. Arena, S. Gentile, F. G. Gulino, D. Sciotto, C. Sgarlata, Tetrahedron Lett. 45 (2004) 7091] arene (SC6A) and cationic surfactant cetyltrimethylammonium bromide (CTAB) were studied by fluorescence spectrometry. A 1:1 stoichiometry for the complexation was established and the complex constant was also calculated by a deduced equation. It was found the fluorescence of the complex could be remarkably quenched by an appropriate amount of ceftriaxone sodium (CTRX). Based on the results, a novel spectrofluorimetric method for determination of CTRX was developed with a linear range of 9.2×10⁻⁷-8.5×10⁻⁵ mol L⁻¹ and a detection of 3.5×10⁻⁷ mol L⁻¹. The proposed method was used to determine CTRX in their commercial preparations with satisfactory results. Moreover, the probable interaction mechanisms of the systems were also discussed.