Authors: Raji Heyrovska
Comments: 3 pages
Exactly today fifteen years ago, the author arrived at the unique result that the ground state Bohr radius of the hydrogen atom is divided into two parts pertaining to the electron and proton, the ratio of which was amazingly a constant. This constant turned out to be the Golden ratio, a mathematical constant, known from ancient times to appear in many spontaneous creations of Nature, big and small. Further work showed that the interatomic distances in alkali metals and halogens are divided exactly into their cationic and anionic radii by the Golden ratio, the sums of which accounted precisely for the interionic distances in alkali halides. This cascaded over the years into the additivity rule of atomic and or ionic radii in the structures of small as well as large molecules. This is summarized in this short paper.
In this work, the As(V) sorption onto magnetic separable poly p-phenylenediamine-thiourea-formaldehyde polymer (MpPDTF) published by Elwakeel and Al-Bogami was reevaluated using deactivation kinetics model (DKM). As the result, the reaction order and the activation energies were newly calculated.
Magnesium gluconate is a classical organometallic pharmaceutical compound used for the prevention and treatment of hypomagnesemia as a source of magnesium ion. The present research described the in-depth study on solid state properties viz. physicochemical and thermal properties of magnesium gluconate using sophisticated analytical techniques like Powder X-ray diffraction (PXRD), particle size analysis (PSA), Fourier transform infrared (FT-IR) spectrometry, ultraviolet–visible (UV–Vis) spectroscopy, thermogravimetric analysis (TGA)/differential thermogravimetric analysis (DTG), and differential scanning calorimetry (DSC). Magnesium gluconate was found to be crystalline in nature along with the crystallite size ranging from 14.10 to 47.35 nm. The particle size distribution was at d(0.1)=6.552 µm, d(0.5)=38.299 µm, d(0.9)=173.712 µm and D(4,3)=67.122 µm along with the specific surface area of 0.372 m2 /g. The wavelength for the maximum absorbance was at 198.0 nm. Magnesium gluconate exhibited 88.51% weight loss with three stages of thermal degradation process up to 895.18 °C from room temperature. The TGA/DTG thermograms of the analyte indicated that magnesium gluconate was thermally stable up to around 165 °C. Consequently, the melting temperature of magnesium gluconate was found to be 169.90 °C along with the enthalpy of fusion of 308.7 J/g. Thus, the authors conclude that the achieved results from this study are very useful in pharmaceutical and nutraceutical industries for the identification, characterization and qualitative analysis of magnesium gluconate for preformulation studies and also for developing magnesium gluconate based novel formulation.
In this communication, the adsorption of benzothiophene sulfone (BTO) over clay mineral adsorbents [Fuel 205 (2017) 153–160] was reevaluated using deactivation kinetics model (DKM). As the result, the reaction order and the activation energies were newly calculated.
Keywords: Adsorption, Kinetics, Modeling
Authors: Sulaiman Mujoobe
Comments: 36 Pages. CC-BY LICENCE: Anyone can share, reuse, remix, or adapt this material for any purpose, providing the original authors are credited and cited.
ABSTRACT: The main purpose of this paper is to attempt to give a detailed step by step explanation of how data is collected and statistically treated during an analytical method development and validation protocol for Quality Control of Pharmaceutics. In most cases, modification to a given manufacturing process, formulation or synthetic pathway during a drug development program may necessitate changes to existing analytic methods. As a consequence, this change may require additional transfer and or validation studies. Effective method development in a pharmaceutical industry is aimed at ensuring that analytical methods meet the objectives required at each stage of drug development using the least resources available of which developmental time and cost are the main targets. Method validation involves demonstrating that these methods are suitable for their intended use as required by regulatory agencies. Method transfer is the formal process of assessing the suitability of methods in another laboratory. These studies involve numerous steps taken, according to a given Standard Operating Procedure (SOP) to collect data. Data analysis usually encompasses confusing mathematical manipulations that may require extensive knowledge of statistics. Although most papers and articles on method development and validation indicate how data is collected, very few give the final acceptance result and show how it was calculated. This paper therefore fills this gap by illustrating, following a hypothetical Standard Operating Procedure: MUJ-256-B dated 16th July 2015 from a hypothetical JBXY Pharmaceuticals, how to develop and validate a method to identify and quantitatively determine the concentration of the active pharmaceutical ingredient; (±) 1, 2, 3, 9-tetrahydro-9-methyl-3-[(2-methyl-1H-imidazol-1-yl) methyl]-4H-carbazol-4 one, monohydrochloride, dihydrate (Ondansetron hydrochloride dihydrate) in Ondansetron hydrochloride 4mg/5ml Syrup (Nausetron) by Reversed-Phase High Performance Liquid Chromatography.
Keywords: Acceptance Criteria, Hypothesis Testing, International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use; Method Transfer; Ondansetron; Pharmaceutical; Statistics; Reversed-Phase; Biostatistics; Statistical Treatment; Quality Assurance; Quality Control.
Authors: Raji Heyrovska
Comments: 15 pages
Presented here is a collection of papers by the author with reference data on atomic and ionic radii which account for the chemical bonds in inorganic, organic and biological molecules, and relevant figures.