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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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Journal of Thermal Analysis and Calorimetry
Authors: A. Apicella, C. A. Beretta, M. A. Castiglione-Morelli, E. Martuscelli, L. Nicolais, and M. R. Nobile

Calorimetric and rheological characterizations of thermosetting resin formulations containing a novalac epoxy resin hardened with 60 to 120 parts per hundred of methylated maleic acid adduct anhydride are described. The calorimetrically determined epoxy conversion has been related to the gelation limits theoretically calculated from Flory's non-linear copolymerization theory and experimentally verified in rheological tests.

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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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, 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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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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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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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  

N-[11C]methyl-1-(1,3-benzodioxol-5-yl)-2-butanamine ([11C]MBDB) 3 was prepared by methylation of the demethyl precursor BDB with [11C]CHI. The radiosynthesis was optimized with regard to temperature, reaction time and amount of precursor, best results (i.e., 84% radiochemical yield, based on [11C]CH3I activity) were obtained using 3 mg BDB at a reaction temperature of 130 °C in 8 minutes. With respect to a facilitated workup routine, productions were performed with 0.6 mg BDB at 110 °C for 10 minutes, yielding more than 50% of 3. The radiochemical purity of the final tracer solution was >98%, the specific activity was determined to be 300 GBq/mol (8000 Ci/mmol). Biodistribution, studies in rats showed two major metabolic pathways as indicated by an increasing liver uptake (9.1% ID/organ at 5 minutes to 21% ID/organ at 30 minutes) and a high urine activity (up to 16% ID/g). In brain tracer uptake was more than 1%, with a brain to blood ratio of almost 12 resulting from a very rapid blood clearance of 3.

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