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Abstract  

The separation of Tc(VII) from Mo(VI) by thin-layer and paper-chromatography is discussed. Some aspects concerning the formation and identification of lower oxidation states of Tc(VII) are also mentioned. Finally, a spot test is recommended for the determination of Mo(VI) and Al, which can be contaminants in the Tc(VII) solution eluted from the99Mo column, filled with Al2O3.

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Abstract  

Cefotaxime, a cephalosporin antibiotic, used to treat bacterial infections was investigated to label with 99mTc. Labeling was performed using sodium dithionite as a reducing agent at 100 °C for 10 min and radiochemical analysis involved ITLC and HPLC methods. The stability of labeled antibiotic was checked in the presence of human serum at 37 °C up to 24 h. The maximum radiolabeling yield was 92 ± 2%. Bacterial binding assay was performed with S. aureus and the in vivo distribution was studied in mice. Images showed minimal accumulation in non-target tissues, with an average target/non-target ratio of 2.89 ± 0.58.

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Abstract  

Analysis of lichens and mosses were routinely performed by 17 laboratories from 15 countries around the world, participating in a project coordinated by the International Atomic Energy Agency (IAEA). To improve and control the quality of such determinations, the IAEA organized a two-round interlaboratory exercise, which allowed the detection and removal of most of the pitfalls observed in the determination of 27 elements. The application of instrumental neutron activation analysis helped reveal poor recoveries in some laboratories due to incomplete digestion for a number of elements. The exercise emphasized the importance of achieving comparability of chemical measurements to a recognized reference.

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An HPTLC method has been established for analysis of α-solanine and α-chaconine in potatoes during industrial processing. Chromatography is performed on silica gel plates in a horizontal developing chamber. Post-chromatographic derivatization by dipping the plates into antimony(III) chloride solution and subsequent heating results in red chromatographic bands. The reaction products are detected and quantified densitometrically by reflectance scanning at 560 nm. The limit of quantification is approximately 30 ng per zone. Depending on the matrix of the sample, the detection limit for both compounds is between 5 and 20 ng per zone. The calibration plots for α-solanine and α-chaconine are linear in the range 30 to 700 ng. Polynomial regression with low relative standard deviation is possible from 30 to 1500 ng. Easy sample preparation, ruggedness, and high selectivity are outstanding advantages of this method. The method is applicable to samples at all stages of processing — raw, peeled, blanched, cooked, and dried potatoes, and byproducts such as peel, waste mash, and processing waters. After steam-peeling, the total glycoalkaloid (TGA) concentration in the analyzed cultivar Karlena was reduced to approximately 25% of its original content in the whole potato, which can increase to more than 1000 mg TGA kg −1 fresh weight. Because of further leaching during processing, the commercial potato flakes tested contained less than 6 mg TGA kg −1 reconstituted mashed potatoes. Food with TGA concentrations of up to 100 mg kg −1 is regarded as completely safe. The ratio of α-chaconine to α-solanine was between 4:1 to 2:1 for all the samples analyzed.

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, A Concise Quality Control Guide on Essential Drugs and Other Medicine , Global Pharma Health Fund (GPHF) , 2008 . [19] International Conference on Harmonisation, Harmonised Tripartite Guideline: Validation of

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Abstract  

fac(S)-[Rh(aet)3] (aet = 2-aminoethanethiolate) is N3S3 metalloligand which can coordinate to transition metal ions to form S-bridge polynuclear complexes. The reaction was carried out between 99mTcO4Na and fac(S)-[Rh(aet)3] in the presence of SnCl2·2H2O. A complex analogous to [Re{Rh(aet3)}2]3+ is formed.6 A simple method for radiolabeling of fac(S)-[Rh(aet)3] with 99mTc has been developed and radiolabeling efficiency was higher than 99%. Effect of SnCl2·2H2O concentration, electrophoresis, HPLC, UV-Visible absorption spectra and biodistribution studies in rats were performed. Higher uptake by kidneys showed rapid distributions of the labeled fac(S)-[Rh(aet)3]. Liver uptake was significant, stomach, lungs and intestine uptake was high at 4 hours post injection time.

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A new, simple, reliable, and validated high-performance thin-layer chromatographic (HPTLC) method has been developed for the simultaneous quantitation of four bioactive markers, ursolic acid (1), betulinic acid (2), β-sitosterol (3), and lupeol (4) in the stem and root barks of Alstonia scholaris. Extraction efficiency of the targeted markers from the bark matrixes with organic solvents using cold percolation, hot extraction, and ultrasonic extraction were studied, which showed that ultrasonic extraction was best for sample preparation. The separation was achieved on silica gel 60F254 HPTLC plates using chloroform-methanol (99:1 v/v) as mobile phase. The quantitation of four markers was carried out using the densitometric reflection/absorption mode at 680 nm after post chromatographic derivatization using vanillin-sulphuric acid reagent. The linear regression analysis data for the calibration plots showed a good linear relationship (r 2 ≥ 0.998) in the concentration range 2–10 μg per spot for the ursolic acid and lupeol and 4–20 μg per spot for the betulinic acid and β-sitosterol with respect to area. The method was validated for peak purity, precision, accuracy, robustness, limit of detection (LOD), and quantitation (LOQ). Method specificity was confirmed using retention factor (R F) and visible spectral (post chromatographic scan) correlation of marker compounds in the samples and standard tracks.

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Summary

To control the quality of Euonymus fortunei (Turcz.) Hand.-Mazz., a simple and reliable method of high-performance liquid chromatography (HPLC) coupled with photodiode array detector (PAD) was developed for both fingerprint analysis and quantitative determination. Four representative flavonoids, namely, kaempferol-3-O-β-D-glucopyranosyl-(1→4)-α-L-rhamnopyranosyl-7-O-β-D-glucopyranosyl-(1→4)-α-L-rhamnopyranoside (I), kaempferol-3,7-O-α-dirhamnopyranoside (II), apigenin-7-O-β-D-glucopyranoside (III), and kaempferol-3-(4″-O-acetyl)-O-α-L-rhamnopyranoside-7-O-α-L-r hamnopyranoside (IV) isolated from E. fortunei, were used as reference compounds and simultaneously determined by the validated HPLC method. The unique properties of the chromatographic fingerprint were validated by analyzing 11 batches of E. fortunei, E. japonicus, E. laxiflorus, E. myrianthus, and E. hamiltonianus samples. Our results revealed that the chromatographic fingerprint combined with similarity measurement could efficiently identify and distinguish E. fortunei from the other investigated Euonymus species.

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Abstract  

The Radiochemistry Department of Rotem Industries produces 131I hard gelatin capsules for the treatment and diagnosis of different thyroid disorders. Each capsule is designated for a specified patient according to the physician's decision that is based on the patient's morbid status. GMP (Good Manufacturing Practices) requirements have been implemented throughout the production process resulting in the accreditation by the Israeli Ministry of Health. A computerized system has been developed and is used as a QC tool throughout the process of 131I capsule production. The request by the physician for capsules of various activities are introduced into the system and the process from production through packaging and external radiation monitoring is computer-controlled. The system prevents the possibility of double orders, out of specification production and enables documentation of data regardless of production date.

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