A Novel Synchronic Estimstion of Metronidazole, Ciprofloxacin and Doxycycline by RP-HPLC in Bulk and Pharmaceutical Formulation

Aim: To design simple, rapid, new analytical method for estimation of Metronidazole, Ciprofloxacin Doxycycline by using RP-HPLC in bulk and pharmaceutical dosage form. Study Design: Estimation of Metronidazole, Ciprofloxacin Doxycycline by using RP-HPLC in bulk and pharmaceutical dosage form was planned and executed. Place and Duration of Study: Chalapathi Drug Testing Laboratory, Chalapathi Institute Of Pharmaceutical Sciences, Lam, Guntur-522034, Andhra Pradesh, India during the period of November 2019 to February 2020. Methodology: Metronidazole is an antibiotic and antiprotozoal medication. It is used either alone or with other antibiotics to treat pelvic inflammatory disease, endocarditis and bacterial vaginosis. Ciprofloxacin is an antibiotic used to treat a number of bacterial infections. Doxycycline is a tetracycline antibiotic that fights bacteria in the body. The study was carried out on SHIMADZU Prominance-i, LC-2030C system equipped with Shim-pack Gist (250 x 4.6 mm, 5μm) column and mobile phase was optimized by using mixture of methanol and 0.25mM potassium phosphate buffer in the ration of 60:40 v/v at a flow rate of 0.8 ml/min. The wavelength was set as 282nm at ambient temperature by injecting 20µl of solution and the run time was fixed for 10 min. Results: Linearity plot was constructed for concentration range of 5-15µg/ml for Metronidazole,5-15µg/ml for Ciprofloxacin and 1-8µg/ml for Doxycycline standard solutions. It shows best regression coefficient and y/s values. The accuracy of the proposed method was determined by performing recovery studies and was found between 98-102%. The repeatability testing for both sample and standard solutions the %RSD was found as <2.0% which is within the acceptable limits showing that the method is precise as well. The LOD and LOQ were found to be 0.33 and 0.99 µg/ml for Metronidazole, 0.33 and 0.99 µg/ml for Ciprofloxacin, 0.08 and 0.25 µg/ml for Doxycycline respectively. The proposed method was successfully applied for the pharmaceutical dosage form of Metronidazole, Ciprofloxacin Doxycycline and it was as economic, eco-friendly with less retention time around 10.0 min. Conclusion: The proposed method was validated in terms of linearity, range, Accuracy, precision, Specificity, Robustness. Method was successfully applied to the estimation of Metronidazole, Ciprofloxacin Doxycycline in combined marketed pharmaceutical dosage form.

A new sensitive HPLC/UV method for simultaneous determination of paclitaxel, sorafenib and omeprazole in standard solutions and spiked plasma: Application to in-vitro and in-vivo evaluation of paclitaxel polymeric nanoformulations

Purpose: To develop a simple, novel, sensitive and rapid reverse phase high performance liquid chromatographic method for simultaneous determination of paclitaxel, sorafenib and omeprazole in standard solutions and spiked human plasma and its application to the in-vitro and in-vivo evaluation of paclitaxel polymeric nanoparticle formulations.Methods: The method was tested for the assessment of paclitaxel, omeprazole and sorafenib using tamoxifen citrate as internal standard. The analysis was performed at a wavelength of 235 nm using Thermo HS C18 column, 40 °C column oven temperature, acetonitrile and water (70:30 v/v, pH 3.37 adjusted with phosphoric acid) as a mobile phase and at a flow rate of 0.8 ml/min. All analytes were extracted by simple protein precipitation method using acetonitrile. The linearity was assessed in the concentration range of 1 - 2000 ng/mL for paclitaxel, omeprazole and sorafenib.Results: The developed chromatographic method effectively separated omeprazole, paclitaxel, sorafenib and IS with retention time of 3.93, 5.18, 6.43 and 9.93 min, respectively. The chromatograms of the three target compounds and IS showed good resolution and peak separation. The LOD of the method was 1, 5 and. 5 ng/mL while the LOQ was 2, 7.5 and 10 ng/mL, for paclitaxel, sorafenib and omeprazole, respectively.Conclusion: The proposed RP-HPLC–UV method for the assessment of paclitaxel, sorafenib and omeprazole in standard solutions and spiked plasma is simple, economical, sensitive and robust. The method is also suitable for the analysis of paclitaxel in nanoformulations and for its pharmacokinetic studies in an animal model.

Development of multispectral optoelectronic system 19ТVА-001 for system 3М47-01

The developed optoelectronic system can be used for detecting a wide range of aircraft. Its performance is based on classical methods of optical detection as well as on non-standard solutions. To determine the product capabilities and meet the customer’s requirements, we conducted simulation modelling of the feasibility of proposed solutions at the development stage. The results of field tests and sea trials promise quite accurate prediction of the system’s performance outcome.

Innovative NSAID dosage forms: lornoxicam suppositories and their standardization

The article presents the studies on the development of a method for the quantitative determination of lornoxime in suppositories using UV spectrophotometry. The optical densities of the test solutions were recorded at a wavelength of 375 nm. The absorption spectra of standard solutions of lornoxicam, as well as of tested solutions of suppositories were obtained. The relative standard deviation was 2.31%.

Development of multi-systems for measurement of radionuclide absolute activity

The development of a multi-systems triple-to-double coincidence ratio (TDCR) and coincidence 4pb-g methods, based on liquid scintillation to radionuclide standardization is presented in this work. The adjustments of multi-systems were made using standards of 3H and 14C and 60Co. The initial stage was performing measurements of pure beta-emitters 3H, 63Ni, and 90Sr90Y standard solutions by TDCR. The results were consistent within the standard uncertainty. Measurements will be performed with a beta-gamma 60Co in a comparison to the SIR / BIPM to assess the multi-system's performance.

CGRP measurements in human plasma – a methodological study

Background Calcitonin gene-related peptide plasma levels have frequently been determined as a biomarker for primary headaches. However, published data is often inconsistent resulting from different methods that are not precisely described in most studies. Methods We applied a well-proven enzyme-linked immunosorbent assay to measure calcitonin gene-related peptide concentrations in human blood plasma, we modified parameters of plasma preparation and protein purification and used calcitonin gene-related peptide-free plasma for standard solutions, which are described in detail. Results Calcitonin gene-related peptide levels are stable in plasma with peptidase inhibitors and after deep-freezing. Calcitonin gene-related peptide standard solutions based on synthetic intercellular fluid or pooled plasma with pre-absorbed calcitonin gene-related peptide influenced the measurements but yielded both comprehensible results. In a sample of 56 healthy subjects the calcitonin gene-related peptide plasma levels varied considerably from low (<50 pg/mL) to very high (>500 pg/mL) values. After a 12-hour exposure of these subjects to normobaric hypoxia the individual calcitonin gene-related peptide levels remained stable. Conclusion Buffering with peptidase inhibitors and immediate freezing or processing of plasma samples is essential to achieve reliable measurements. Individuals show considerable differences and partly high calcitonin gene-related peptide plasma levels without detectable pathological reason. Thus plasma measurements are suited particularly to follow calcitonin gene-related peptide levels in longitudinal studies. The use of data for this study was approved by the Ethics Committee of the Medical University of Innsbruck ( https://www.i-med.ac.at/ethikkommission/ ; EK Nr: 1242/2017).

The Bethe-Ansatz approach to the $$ \mathcal{N} $$ = 4 superconformal index at finite rank

We investigate the Bethe-Ansatz approach to the superconformal index of $$ \mathcal{N} $$ N = 4 supersymmetric Yang-Mills with SU(N) gauge group in the context of finite rank, N. We explicitly explore the role of the various types of solutions to the Bethe-Ansatz Equations in recovering the exact index for N = 2, 3. We classify the Bethe-Ansatz Equations solutions as standard (corresponding to a freely acting orbifold T2/ℤm× ℤn) and non-standard. For N = 2, we find that the index is fully recovered by standard solutions and displays an interesting pattern of cancellations. However, for N ≥ 3, the standard solutions alone do not suffice to reconstruct the index. We present quantitative arguments in various regimes of fugacities that highlight the challenging role played by the continuous families of non-standard solutions.

Determination of adenine nucleotides by the modified method of high-performance liquid chromatography

Adenine nucleotides (ATP, ADP and AMP) play a central role in the regulation of metabolism and energy: they provide the energy balance of the cell, determine its redox state, act as allosteric effectors of a number of enzymes, modulate signaling and transcription factors and activate oxidation or biosynthesis substrates. A large number of methods have been developed to determine the level of ATP, ADP and AMP, but the most universal and effective method for the separation and analysis of complex mixtures is the reversed-phase high-performance liquid chromatography method (RP-HPLC). The aim of this study is to determine the optimal conditions for the qualitative separation and quantitative determination of standard solutions of ATP (1 mmol/l), ADP (0,5 mmol/l) and AMP (0,1 mmol/l) by RP-HPLC. The degree of separation of adenine nucleotides was estimated by the time of peak output in the chromatogram. To achieve the goal, the following tasks were set: assess the effect of the temperature of the analysis on the separation and change of the release time of the analytes in the chromatogram; determine the most optimal composition of the mobile phase for the separation of ATP, ADP and AMP in the chromatogram (the content of the organic solvent in the solution); to identify the effect of pH of the mobile phase on the separation of standard solutions of adenine nucleotides; set the optimal molarity of the mobile phase for the separation of ATP, ADP and AMP in the chromatogram. It was found that the temperature of the analysis does not affect the quality of peak separation, while the composition and pH of the mobile phase have a significant effect on the complete and clear separation of the studied nucleotides in the chromatogram. It was determined that the analysis temperature of 37°C and the mobile phase of 0.05 M KH2PO4 (pH 6.0) are optimal for separating the peaks of adenine nucleotides.

Anti- Parkinsonian Drug Estimation by RP-HPLC

Aim: The main aim of the current study is to give best and simple method for the estimation of antiparkinsonian drugs named Carbidopa, levodopa and entacapone. Study Design: Simultaneous estimation of Carbidopa, levodopa and entacapone was performed by using Quadrapumped (SHIMADZU Prominance-i, LC-2030C) RP-HPLC equipped with PDA detector. Place and Duration of Study: Chalapathi Drug Testing Laboratory, Chalapathi Institute Of Pharmaceutical Sciences, Lam, Guntur-522034, Andhra Pradesh, India during the period of August 2019 to February 2020. Methodology: The assets of the study can determined as the process of qualification and quantification was done on SHIMADZU Prominance-i, LC-2030C system equipped with Phenomenex ODS (150 x 4.6 mm, 5μm) column and mobile phase was optimized using combination of acetonitrile and 0.1% ortho phosphoric acid in the ration of 50:50 v/v at a flow rate 1.0 ml/min. The wavelength was set as 270nm at ambient temperature by injecting 20µl of solution and the run time was fixed for 5 min. Results: Calibration plot shown best regression over the concentration range of 5-160 µg/ml of Carbidopa, Levodopa and Entacapone standard solutions. The LOD and LOQ were found to be 0.85 and 2.54 µg/ml for Entacapone, 0.24 and 0.71 µg/ml for Levodopa, 0.14 and 0.43 µg/ml for Carbidopa respectively. The accuracy of the proposed method was determined by performing recovery studies and was found to be between 98-102%. The repeatability testing for both sample and standard solutions was found as %RSD<2.0% which is within the acceptable limits showing that the method is precise as well. The proposed method was successfully applied for the marketed formulations of Carbidopa, Levodopa and Entacapone tablets. In addition the main feature of proposed method is economic and eco-friendly with less retention time around 5.0 min. Conclusion: Including all the optimized method parameters and statistical results given it can be concluded as a new, simple, sensitive, precise and accurate economical analytical method was developed and validated by RP-HPLC for the detection and quantification of Carbidopa, Levodopa and Entacapone which can be applied to the marketed formulation where there are no official compendial methods reported for this particular combination. The high sensitivity (LOD), mobile phase utilized and run time (=5) can be determined as an important features for this proposal.