Development and validation of a LC-MS/MS method for simultaneous quantification of Ivabradine and Metoprolol in rat plasma.

The combination of Ivabradine (IVA) and Metoprolol (MET) was approved by US-FDA for symptomatic treatment of chronic stable angina pectoris. Hence, a potential analytical method that can simultaneously quantify these two drugs is required. In view of this, a novel and fully validated LC-ESI-MS/MS method has been established for the quantification of IVA and MET in rat plasma. Analytes and their deuterated analogues were quantitatively extracted from rat plasma by protein precipitation technique. The analytes were separated using acetonitrile-water consisting 0.1% orthophosphoric acid buffer (30:70 v/v) as a mobile phase with a flow-rate of 1.0 mL/min and 5 min run time on Waters, X-Bridge-C18 (150× 4.6 mm, 3.5 µm) analytical column. The multiple reaction monitoring transitions, m/z 638.14 â†’ 124.22 for IVA, 498.33 â†’ 110.59 for MET; 644.37 â†’ 130.41 for IVA-D6 and 504.46 â†’ 116.28 for MET-D6 were chosen to achieve high selectivity in the analysis. The method exhibited great improvement in sensitivity and good linearity over the concentration range of 0.1-1.5 ng/mL for IVA, 1.0-15.0 ng/mL for MET, with satisfactory precision and accuracy according to USFDA guidelines. Accuracy was within 99.71-100.3% and 99.9-100.31% for IVA and MET. The intra- and inter-day precision ranged between 0.048 and 12.68% and 0.1-2.66% CV for IVA and MET respectively. Further, the results of the pharmacokinetic parameters including Cmax, tmax, AUC0-t, AUC0-∞ and t1/2 values of drugs indicated that the method is useful for successful quantification of the drugs in rat plasma. The developed method is significant and is useful for simultaneous quantification of IVA and MET.

Synthesis, Characterization and Antimicrobial Activities of Copper Derivatives of NHC-II Complexes.

BACKGROUND: Caffeine, 1, 3, 7-trimethylxanthine is one of the xanthine derivatives that are for the most part utilized as a part of solutions as diuretics. The Cu (II) complexes have been synthesized from the N-heterocyclic carbene ligands. MATERIALS AND METHODS: The Cu (II) NHC complexes were characterized using analytical and spectral techniques. Antibacterial and antifungal activities of the Cu (II) NHC complexes were determined using the reported techniques. The SOD activity was assayed using nitrobluetetrazolium as O2 scavenger. RESULTS: The X-band ESR spectra of the copper complexes in DMSO solution at 300 and 77 K were recorded and their salient features are reported. The in vitro biological screening effects of the investigated compounds were tested against the bacterial species, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris and Pseudomonas aeruginosa and fungal species, Aspergillus niger, Rhizopus stolonifer, Aspergillus flavus, Rhizoctonia bataicola and Candida albicans by serial dilution method. CONCLUSION: The Cu (II) complexes exhibit square planar geometry. A comparative study of inhibition values of the individual metals and their complexes indicate that the complexes exhibit higher antimicrobial activity than the individual metals. Superoxide dismutase and reducing power activities of the copper complexes have also been studied. Depending on the molecular structure, the Cu (II) NHC complex possess promising SOD mimetic activities. Further we are trying to explore more biological properties of Cu (II) NHC complexes in vitro and in vivo.

Development and Validation of Stability-indicating High Performance Liquid Chromatographic Method for the Estimation of Everolimus in Tablets.

The present study depicts the development of a validated reversed-phase high performance liquid chromatographic method for the determination of the everolimus in presence of degradation products or pharmaceutical excipients. Stress study was performed on everolimus and it was found that it degrade sufficiently in oxidizing and acidic conditions but less degradation was found in alkaline, neutral, thermal and photolytic conditions. The separation was carried out on Hypersil BDS C18 column (100×4.6 mm, 5 µ) column having particle size 5 µ using acetate buffer:acetonitrile (50:50 v/v) with pH 6.5 adjusted with orthophosphoric acid as mobile phase at flow rate of 1 ml/min. The wavelength of the detection was 280 nm. A retention time (Rt) nearly 3.110 min was observed. The calibration curve for everolimus was linear (r(2)=0.999) from range of 25-150 µg/ml with limit of detection and limit of quantification of 0.036 µg/ml and 0.109 µg/ml, respectively. Analytical validation parameters such as selectivity, specificity, linearity, accuracy and precision were evaluated and relative standard deviation value for all the key parameters were less than 2.0%. The recovery of the drug after standard addition was found to be 100.55%. Thus, the developed RP-HPLC method was found to be suitable for the determination of everolimus in tablets containing various excipients.