SIMULTANEOUS ESTIMATION OF RELATED COMPOUNDS IN ESOMEPRAZOLE AND NAPROXEN TABLETS BY USING ION PAIR REVERSE PHASE HPLC

Objective: To develop and validate a novel gradient reverse phase HPLC method for quantitative estimation of Naproxen and Esomeprazole impurities in pharmaceutical dosage form.Methods: Chromatographic separation was achieved on X-Bridge C18,150x4.6 mm, 3.5 µm column. Detection wavelength was set at 302 nm. The mobile phase A consists of Buffer and Acetonitrile in the ratio of 90:10, where Buffer was prepared by dissolving di ammonium hydrogen phosphate (2.64 gm per Liter) and 1-hexane sulphonic acid sodium salt (1.0 gm per Liter), pH adjusted to 6.5±0.05 with orthophosphoric acid. A mixture of acetonitrile and 1-propanol in the ratio of 90:10 was used as mobile phase B. Flow rate was set to 0.7 mL/minute in gradient elution mode, with a retention time for Naproxen and Esomeprazole 29 and 46 minute respectively.Results: The calibration curve was linear over the concentration range of 4.621 µg/mL – 99.026 µg/mL for Naproxen and 0.254 µg/mL–3.806 µg/mL for Esomeprazole (r= 0.999). The proposed method was found to be (considered)accurate and precise and linear within the desired range. The limit of quantitation (LOQ) was calculated. The purity angle was found less than purity threshold for forced degradation peaks, which shows there was no interference from the common excipient, known impurities and degradents indicating separation, accuracy and reliability of the method. The method was validated as per ICH guidelines and found to be specific, accurate, linear, precise and stability indicating.Conclusion: A Novel, simple, selective and rapid reversed phase high performance liquid chromatographic (HPLC) method was developed and validated for the estimation of Naproxen and Esomeprazole impurities in pharmaceutical dosage form. Hence, the method can be used for routine analysis in various pharmaceutical industries.Â

Visualisation of stabilising particles at the gas solid interface of metal foams

In this article, we demonstrate a technique to visualise the stabilising particles at the gas solid interface of metal foams by employing metallographic etching. This technique is easy to perform and can be applied on a relatively large sample size. The particles present at the gas solid interface of five different types of foams were investigated. Information on the type of particles and the particle coverage could be obtained from this stud

Inactivation of Chk2 and Mus81 Leads to Impaired Lymphocytes Development, Reduced Genomic Instability, and Suppression of Cancer

Chk2 is an effector kinase important for the activation of cell cycle checkpoints, p53, and apoptosis in response to DNA damage. Mus81 is required for the restart of stalled replication forks and for genomic integrity. Mus81Δex3-4/Δex3-4 mice have increased cancer susceptibility that is exacerbated by p53 inactivation. In this study, we demonstrate that Chk2 inactivation impairs the development of Mus81Δex3-4/Δex3-4 lymphoid cells in a cell-autonomous manner. Importantly, in contrast to its predicted tumor suppressor function, loss of Chk2 promotes mitotic catastrophe and cell death, and it results in suppressed oncogenic transformation and tumor development in Mus81Δex3-4/Δex3-4 background. Thus, our data indicate that an important role for Chk2 is maintaining lymphocyte development and that dual inactivation of Chk2 and Mus81 remarkably inhibits cancer

Open Source, 3D-Printed TrapGuard to Protect Oil-Sealed Vacuum Pumps from Cold Trap Warming

Clean pump oil is critical to the performance and longevity of oil-sealed vacuum pumps. Cold traps charged with cryogens can protect pump oil from solvent contamination but are subject to operator error. Notably, cold traps with evaporated or warmed cryogens do not protect the vacuum pump. Here, we report an open source device to automatically protect oil-sealed vacuum pumps from cold trap warming and facilitate the daily maintenance of cold traps