LC/MS/MS method for the determination of trace amounts of cefmetazole and cefpodoxime proxetil contaminants in pharmaceutical manufacturing environments

Cefpodoxime proxetil

A comprehensive profile of cefpodoxime proxetil including the nomenclatures, formulae, elemental composition, appearance, uses, and applications. The methods which were developed for the preparation of the drug substance and their respective schemes are outlined. The physical characteristics of the drug including the ionization constant, solubility, X-ray powder diffraction pattern, differential scanning calorimetry, thermal behavior, and spectroscopic studies are included. The methods which were used for the analysis of the drug substance in bulk drug and/or in pharmaceutical formulations includes the compendial, spectrophotometric, electrochemical and the chromatographic methods. The other studies which was carried out on this drug substance are including the drug stability, pharmacokinetics, bioavailability, drug evaluation, comparison and several compiled reviews. Finally, more than two hundred references are listed at the end of this profile.

Electrophoretic stacking for sensitive determination of antibiotic ceftazidime in human blood and microdialysates from diabetic foot

An electrophoretic stacking method has been developed for monitoring the therapeutic level of the antibiotic ceftazidime in blood plasma and microdialysates taken from peripheral soft tissues of the lower limbs of patients with diabetic foot syndrome. The biological samples are treated by addition of acetonitrile in an amount of 75% v/v and injected into a capillary in a large volume; after turning on the separation voltage, the residual acetonitrile is forced out of the capillary by the application of hydrodynamic pressure. The clinical samples were separated in an optimised background electrolyte composed of 50 mM chloroacetic acid +20% v/v methanol +0.5% v/v INST coating solution. The attained LOD for ceftazidime equalled 0.42 μg mL^-1 (0.8 μM) and the migration time equalled 3.75 min when using a 25 μm capillary with minimum length of 31.5 cm. The separation was controlled by a maximum voltage of +30 kV and the movement of the analyte was accelerated by a pressure of 50 mbar. The RSD values for intra-day repeatability of the migration time and peak area are 0.14% and 3.8%, respectively; the inter-day values equalled 0.25% for the migration time and 7.3% for peak area, respectively. Pharmacological studies revealed that ceftazidime passes from the blood circulation to the peripheral tissues of the lower limbs with an efficiency of 20%. The introduction of CE control of ceftazidime level in diabetic foot represents a very important improvement in achieving the targeted therapeutic effect.

Occurrence, fate, and risk assessment of vancomycin in two typical pharmaceutical wastewater treatment plants in Eastern China

Vancomycin (VCM) is an antibiotic, known medically as the deadline for defending against bacteria. In this study, the removal and fate of VCM were investigated in each treatment unit at two pharmaceutical wastewater treatment plants (PWWTPs) in eastern China. VCM was present in all wastewater and sludge samples of both PWWTPs. After the treatment procedure (the moving bed biofilm reactor technology for PWWTP1 and the modified anaerobic-anoxic-oxic technology for PWWTP2), total removal efficiencies were up to 99 %, corresponding to a reduction of two orders of magnitude of the influent concentrations in both PWWTPs. The aerobic tank dominated VCM removal. Mass balance flow analyses indicated that biodegradation (99.15 % for PWWTP1 and 99.51 % for PWWTP2) was the principle mechanism for removing VCM, while the contribution of sorption by sludge for both PWWTPs was negligible. However, the results of the environmental risk assessment of VCM in the effluents showed that the maximum trigger quotient values were much higher than 1 in both PWWTPs, indicating the non-negligible environmental and health risks. This is the first report of the fate and risks of VCM in pharmaceutical wastewater, and underscores the importance of PWWTPs as antibiotic pollution sources, even though wastewater management appeared efficient.

Mass Spectral Profile for Rapid Differentiating Beta-Lactams from Their Ring-Opened Impurities

High performance liquid chromatography tandem mass spectrometry (HPLC MS) has been widely used for β-lactam antibiotics determination. However, its application to identify impurities of these frequently used drugs is not sufficient at present. In this job, characteristic profiles of the collision induced dissociation (CID) spectra of both β-lactams and ring-opened β-lactams were extracted from the MS data of six β-lactam antibiotics and their forty-five impurities, and were confirmed by the MS data reported in the literature. These characteristics have been successfully applied to rapid differentiation of β-lactam and ring-opened β-lactam impurities in cefixime, cefdinir, and cefaclor. However, these characteristic profiles can only be obtained under low activating voltage. They did not display in the high energy activated CID spectra. Diagnostic fragmentations for determining the localization of double bond and substituents on the thiazine ring and the side chain were also observed. In addition, several characteristic fragmentations are hopeful to be used to differentiate the configurations of C-2 on the thiazine ring of ring-opened impurities, which is generally disadvantageous of mass spectrometry. Taken together, forty-five impurities were identified from the capsules of cefixime, cefdinir, and cefaclor.

Analysis of cephalosporin antibiotics

A comprehensive review with 276 references for the analysis of members of an important class of drugs, cephalosporin antibiotics, is presented. The review covers most of the methods described for the analysis of these drugs in pure forms, in different pharmaceutical dosage forms and in biological fluids.

Verification of cefmetazole and cefpodoxime proxetil contamination to other pharmaceuticals by liquid chromatography-tandem mass spectrometry

Cross-contamination is a critical issue for pharmaceutical manufacturing, especially for beta-lactam antibiotics. Thus, an analytical method for the simultaneous determination of beta-lactam antibiotics cefmetazole (CMZ) and cefpodoxime proxetil (CPDXPR) contaminants in non-beta-lactam pharmaceuticals was developed using high-performance liquid chromatography-tandem mass spectrometry. The developed method was found to be sensitive at the detection limit of 0.002 ppm for both compounds. Mean recoveries of CMZ and CPDXPR from olmesartan medoxomil (OLM) tablets were 96.7 to 102.2% and 88.9 to 94.2%, respectively. The developed method was successfully applied for the verification of CMZ and CPDXPR contamination to actually manufactured OLM tablets.