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Arapid and simple method for simultaneous quantitative analysis of the natural carbohydrates fructose, glucose, and sucrose in different types of wine (white and red; dry, semi-dry, semi-sweet, and sweet) by OPLC in overrunning mode is presented. The compounds were separated on precoated silica gel F254 OPLC plates with acetonitrile-water 26:4 (v/v) as mobile phase. Visualization was by spraying with a mixed solution of aniline and diphenylamine, then densitometry in absorbance mode was performed at 420 nm. Linear regression analysis of the calibration data was indicative of a good linear relationship between the peak area and the concentration in the range 0.5–5.0 μg per band (r glucose 0.99051, r fructose 0.98547, r sucrose 0.99506). In this paper we give the results obtained from analysis of 49 samples of white and red wines. In the most of the samples we did not find sucrose, only fructose and glucose in different ratios depending on the type of the wine. We found few white and red wine samples for which the content of reducing sugars was not in agreement with the label description. The results obtained for the wines show this OPLC method can be useful for routine monitoring of the quality of commercial wine. Amajor advantage of the method is that it enables simultaneous analysis of approximately 20 samples in less than 2 h.

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Abstract  

The methods used for control of radiochemical purity of99mTc-MDP are presented. TLC method on silica gel, developed with methanol and acetone (11 v/v), was convenient for determination of99mTcO 4 with the content of 2.6±1.2%. The reliable results on detection of99mTc hydrolyzate (2.2±1.3%) and for another99mTc-MDP complex (13.2±2.8%) were obtained by application of ITLC (SA), developed with Sn-MDP. By Sephadex G-25 column chromatography (1.5 cm×5 cm) the separation of99mTcO 4 was not achieved. The range of normal99mTc-MDP biodistribution values in the organs of experimental animals have been determined. The mean value of bone distribution was 8.4±1.13%/g, in muscles 0.071±0.033%/g, while uptake in liver and kidneys was below 5%. Chi-square test and P show that the results on biodistribution of99mTc-MDP in liver, bones and muscles are arranged around their mean values, which is statistically allowed.

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Abstract  

The synthesis of 188Re-MAG3 is described using 188Re, which was obtained from the alumina based 188W/188Re generator. Dependence of the radiolabeling yields of 188Re-MAG3 on reducing agent concentration, Bz-MAG3 concentration, pH, temperature and incubation time was examined. In the case of optimum conditions the yield of 188Re-MAG3 was 98%. TLC and HPLC techniques were employed to monitor the different species formed. Biodistribution study of 188Re-MAG3 was carried out in rats and compared with behavior of 99mTc-MAG3.

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The subject of the article is the evaluation of three acoustical algorithms on industrial production lines. The algorithm is used for the inspection of work-pieces in a noisy industrial environment. High efficiency performance requirements restricted running time and expected precise results make these inspections problematic. A sequential and two parallel algorithms and processing methods for these measurements were developed. These algorithms are real-time and multi-channel processing methods on industrial production lines. They carry out series of precision measurements in the time frame available. After the inspection the quality class and usability of the pieces are determined. These computer-aided inspections are more effective than human measurements because they are more precise, can be repeated multiple times, even with different quality requirements. They are usable on high-speed industrial production lines to obtain results in digital format.

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Abstract  

DSC was used together with other methods of pharmaceutical analysis (spectrophotometry, thin-layer chromatography) to estimate the quality and standardization of two drugs—lipoic acid (polymerization upon melting, purity) and progesterone (melting temperature, polymorphism).

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JPC - Journal of Planar Chromatography - Modern TLC
Authors: Agnė Kučinskaitė, Loretta Pobłocka-Olech, Mirosława Krauze-Baranowska, Vitalis Briedis, Aruñas Savickas, and Małgorzata Sznitowska

SPE and TLC have been used for qualitative and quantitative analysis of salidroside, rosavin, rosarin, and rosin in commercially available dry extracts from Rhodiola rosea roots. The best separation of all the compounds was achieved on silica gel TLC plates with ethyl acetate-methanol-water, 77 + 13 + 10 ( v / v ), as mobile phase. UV detection was performed at λ = 215 nm for salidroside and at λ = 245 nm for the rosavins (rosavin, rosarin, and rosin). Detection limits for salidroside and the rosavins were 90 ng and 60 ng per spot, respectively. Results from quantitative analysis confirmed the manufacturer’s declaration of the amounts of salidroside and the rosavins in the extracts.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Alireza Khorami-Moghadam, Amir Jalilian, Kamal Yavari, Bahram Bolouri, Ali Bahrami-Samani, and Mohammad Ghannadi-Maragheh

Abstract  

Antiangiogenic monoclonal antibodies in combination with therapeutic radionuclides are potential targeted therapy agents in cancer. In this study, bevacizumab was successively labeled with [166Ho]HoCl3 after conjugation with DOTA-NHS-ester with a radiochemical purity of higher than 95% (RTLC). The conjugates were purified by molecular filtration, the average number of DOTA conjugated per mAb was calculated and total concentration was determined by spectrophotometric method and the average chelate to antibody ratio (c/a) for the conjugate used in this study was 5.8:1 and protein integrity experiments (SDS-PAGE). The biodistribution studies in wild-type rats demonstrate a similar pattern to the other radiolabeled anti-vascular endothelial growth factor A (VEGF-A) immunoconjugates. 166Ho-DOTA-bevacizumab is a potential compound for therapy/imaging of VEGF-A expression in oncology.

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Abstract  

The results obtained for radiochemical purity of ITLC (SA) and (SG) using different solvent systems and low voltage electrophoresis are presented in the paper. Radiochemical purities obtained for99mTc-dimethyl IDA (99mTc-HIDA) and99mTc-diethyl IDA (99mTc-EHIDA) are 98.1±0.6% and 98.7±0.5%, respectively. Variable99mTc hydrolyzate contents, depending on the ionic strength of the eluents and on the time interval between labelling and analysis, have been obtained by Sephadex chromatography. The eluent containing Sn-EHIDA inhibits dissociation of99mTc-EHIDA due to dilution of the preparation during elution of the column and yielding only a small percent of Sephadex bound fraction, as compared to other investigated eluents. The range of normal99mTc-IDA biodistribution values in the organs of experimental animals and statistical significance of the difference between these two preparations have also been determined. The results obtained for99mTc-HIDA and99mTc-EHIDA in the liver are 33.9±5% and 25.7±4.7%, respectively p<0.01.

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Summary  

In the present work an improvement of radiochemical neutron activation analysis for determination of nanogram levels of vanadium is described. The method is based on post-irradiation wet ashing and solvent extraction of vanadium with N-benzoyl-N-phenyl-hydroxylamine (BPHA) forming a violet chelate complex in strongly acidic medium. For quality assurance purposes a procedure for determination of the overall chemical yield using spectrophotometry of the V-BPHA complex is described, and possible interferences are evaluated. The procedure was applied to the determination of vanadium in reference materials and selected food samples from Slovenia.

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Abstract  

The radiochemical purity of the three osteopatic ligands:99mTc(Sn)-PyP,99mTc(Sn)-DPD and99mTc(Sn)-MDP has been determined by gel chromatography on Sephadex. The results of the analyses strongly depend on the composition of the eluent. The dilution effect of pure saline as eluent was observed in all the preparations examined. The most sensitive was found to be99mTc(Sn)-PyP. The retention of99mTc activity bound to the gel matrix (99mTc-hydrolyte) was over 30%. The diphosphonates were found to be more stable (retention 10–15%). The retention is substantially lower, i.e. a high recovery of the labeled complexes is obtained when the eluent contains the ligand. The best results are obtained when the eluent contains the same concentrations of ligand and reductant as in the labeled complex. There was no significant difference in the behavior of the given radiopharmaceuticals prepared as a fresh solution and in the freeze-dried kit.

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