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Abstract  

Radio TLC has been used for determining the radiochemical purity and composition of two99mTc-radiopharmaceuticals, available as kits and commonly used for diagnostic imaging. Moreover, the same technique has been applied to detect impurities which decrease the specific activity of131I-derivatized dermatan sulfate, a new potential radiopharmaceutical, and for establishing the best labeling conditions.

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Thermal diesel-like analysis

Quality control by thermal and chemometric analysis

Journal of Thermal Analysis and Calorimetry
Authors: Alexandre G. S. Prado, Rômulo D. A. Andrade, Jez W. B. Braga, and Paulo A. Z. Suarez

pretreatments of the fuel samples. The results for accuracy, uncertainty, and CC β were promising, indicating that the developed model by thermogravimetric analysis is one alternative to be used in the quality control of biofuels. The

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A simple and sensitive high-performance thin-layer chromatographic (HPTLC) method was developed for the evaluation of biomarker lupeol in the leaves of five different species of genus Ficus (Ficus carica, Ficus nitida, Ficus ingens, Ficus palmata, and Ficus vest) belonging to family Moraceae. Chromatography was performed on glass-backed silica gel 60 F254 precoated HPTLC plates with solvents toluene-methanol (9:1, v/v) as the mobile phase. After development, the HPTLC plate was derivatized with p-anisaldehyde reagent, scanned, and quantified at 540 nm. The system was found to give compact spot for lupeol at R F = 0.32 ± 0.01. The precisions and accuracy (n = 6) for lupeol were found to be 1.47–1.64% and 1.63–1.86%, and 99–100% and 99.4–99.7%, respectively, for inter-day and intra-day. Lupeol was found to be present in four species, i.e., F. carica (0.4%, w/w), F. nitida (1.4%, w/w), F. palmata (0.33%, w/w), and F. vest (0.59%, w/w), while it was absent in F. ingens. The statistical analysis proved that the developed method is reproducible and selective. The developed method can be used as an important tool to assure the therapeutic dose of active ingredients in herbal formulations as well as for standardization and quality control of bulk drugs and in-process formulations. This method can also be employed for the further study of degradation kinetics and determination of lupeol in plasma and other biological fluids.

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Abstract  

The use of serpentine as a potential nuclear shielding material necessitates a chemical quality control of the samples before its use in reactors. With this in view, characterization of these mineral samples was carried out using inductively coupled plasma atomic emission spectrometry (ICP-AES) and Instrumental neutron activation analysis (INAA) methods. The analytical results obtained by both ICP-AES and NAA techniques were found to be comparable. Na, Cr, Co, Zn, and Cu were found to be present in all samples of Indian origin while Ga, Ag, Ni, and Cd were found to below the limits of detection. A comparison on the detection limits of elements of interest was also carried out by both the analytical techniques and found to be in good agreement. An infrared spectroscopic investigation was also carried out on all the mineral samples. Bands at 3,689 and 3,648 cm−1 were attributed to inner and outer hydroxyl stretching of Mg–OH, respectively. The weak and broad band centered around 3,416 cm−1 was assigned due to the stretching vibrations of the adsorbed water molecules while three bands at 1076, 1022 and 968 cm−1 were prescribed to the vibrations of the SiO4 tetrahedra.

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Abstract  

The effectiveness of the neutralization process on heavy metals precipitated in sludge has been evaluated using instrumental neutron activation analysis (INAA) facilities at the South African Nuclear Energy Corporation (Necsa). The elemental concentrations of Th, Fe, Ag, Co, Cr, As, Au and K were reduced after the neutralization process with the exception of Mn and Sn which appeared to be enhanced by the neutralization process. Even though the neutralization process was targeted at the basic ferric arsenate compound, it was found to be effective in reducing other elemental concentrations. The variations in the geochemical compositions of the sulphidic ores during treatment at various stages also showed that physical processing stages do not significantly alter the elemental concentrations in the feed materials, however, the chemically active processing stages do. Also, the enhancement of the elements at the chemical stages depends on total quality control, where the application was not very repeatable the pattern of variation of elements at some stages was found to be irregular irrespective of the ore grade. The elements; Sn, Fe, Th, K, Au, Ag, As, Cr, and Co were enhanced in almost all the chemically active stages. Au was much more enhanced during flotation and bio-oxidation processes. Correlation analysis performed to determine the distribution patterns show that Fe, As, Ag and Co are geochemically associated and might be enriched simultaneously.

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Summary

Background: The fruits of Benincasa hispida (Thunb.) Cogniaux, a ‘rasayana’ in ‘Ayurveda’, are enriched with several secondary metabolites, and rutin is one of them. Fruits are used for their anabolic, brain tonic, carminative, diuretic, memory enhancer, refrigerant, and vitalizer properties. Objective: In view of the fact that herbal medicines and/or products are facing challenges towards global acceptance due to the lack of universally accepted standardization method (s), the aim of the current investigation was to develop and validate a high-performance thin-layer chromatography (HPTLC)-densitometry method for the quantification of rutin in the hydroalcoholic extracts of the fruit pulp of B. hispida (HABH). Materials and methods: The separation was achieved in a solvent system consisting of ethyl acetate-formic acid-acetic acid-water at a ratio of 7.2:0.7:0.7:1.4 by volume on a TLC aluminum plate pre-coated with silica gel 60 F254. Quantifications were performed by densitometric scanning under a deuterium lamp at a wavelength of 268 nm in the absorbance mode. The precision, accuracy, and reproducibility of the HPTLC method were validated by the International Conference on Harmonization (ICH) guidelines. Results: The mobile phase employed for HPTLC/TLC resulted in good separation for rutin (R F = 0.357). The limit of detection and limit of quantification of the analysis were found to be 0.1 and 0.3 µg per band, respectively. The rutin concentration in the HABH was found to be 178.28 ± 3.62 µg in 10 mg of the extract. Conclusion: The method developed here is simple, fast, reliable, and sensitive and can be implemented in the analysis and routine quality control of B. hispida formulations containing rutin.

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Abstract  

The increasing concentration of Pt, Pd and Rh in the environment is mainly due to the release of these elements from the catalytic converters of the motorvehicles. This situation makes it necessary to carry out metallotoxicological experiments on both cell cultures and laboratory animals, in order to assess their impact on living organisms after a Long Term and Low Level Exposure (LLE). Both nuclear reactionsnatIr(p,xn) andnatOs(α,xn) were investigated in the energy range up to 45 MeV for protons and 38 MeV for alpha-particles, in order to optimize the irradiation parameters for the production of188,189,191Pt. Several sets of thin- and thick-target excitation functions were determined experimentally by cyclotron irradiation at both Milano and Ispra cyclotrons. This paper reports the irradiation parameters studied and adopted and two radiochemical procedures for the separation of radio-Pt from an Os target, as well as from ruthenium, iridium and gold impurities. These procedures were used to obtain very high specific activity Pt radionuclides in No Carrier Added (NCA) form. Radionuclidic, radiochemical and chemical purity measurements were carred out by the use of several techniques like ψ-spectrometry, ion-exchange radio-chromatography, atomic absorption spectrometry and neutron activation analysis.

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Abstract  

DTPA-Octreotide(Pentetreotide), a somatostatin analogue which can bind specifically and with high affinity to somatostatin receptor in vitro and vivo, labeled with99mTc by tin reduction in acetate buffer, has been characterized by Reverse-phase High performance Liquid Chromatography. The effect of different solvents, mobile phase pH, linear gradient and the injected volume on the separation efficiency was evaluated. The results show that the separation efficiency is best using μBondapak-C18 (300×3.9 mm2), linear gradient of 40% to 80% methanol (1.0 ml/min) in 0.05M acetate buffer (pH 5.5) over a 30 min period and maintaining for another 10 min. The labeled product is a mixture which mainly consists of five components (a, b, c, d, e) successfully proved by HPLC. Paper chromatography is also evaluated in this paper. It may be used to determine the radiochemical purity of the labeling product, but is not a good choice for the verification each components.

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The quality assessment of commercial soybean oils was evaluated on the basis of chemical and thermal analyses. The most substantial chemical parameters, viz. the density, refractive index and saponification, iodine and acid numbers were estimated. The thermal parameters were determined on the grounds of the TG and DTG curves. There are temperatures for the onset, end and successive mass losses. To find the relation between the chemical and thermal parameters, regression and principal component analyses were applied. The results of principal component analysis indicate that the TG and DTG techniques are at least in equal degree useful in defining the quality of soybean oils, as compared with the chemical analyses.

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