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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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Abstract  

Good manufacturing practices specify that a well-type scintillation NaI(Tl) crystal detector has to be validated in order to detect radioactivity from any radiopharmaceutical used to obtain radiopharmacokinetic parameters. A 5 cm well-type NaI(Tl) scintillation detector was coupled to a multi-channel analyzer centered at the 140 keV 99mTc peak with a 20% window. The area represents counts per minute (cpm). All the net cpm were decay corrected. The activity source was 99mTc-glucarate developed as an imaging agent for acute myocardial infarction. Wistar rats were injected in a tail vein with 0.1 ml (3.7 MBq) of 99mTc-glucarate solution and 13 blood samples were taken. The cpm were the input data for the WINNONLN program which calculates radiopharmacokinetic parameters. The detector's efficiency for 99mTc was 15.03% and the sensitivity 1.12 kBq/ml in plasma. The response was linear between 0.31-14.3 kBq/ml of 99mTc-glucarate. The maximum assay variation coefficient was 2.79 and recovery of 99mTc-glucarate in plasma was 99.8%±0.2%. LOD was 0.31 kBq and LOQ = 1.12 kBq in plasma samples. 99mTc-glucarate follows a two-compartment model of distribution with Vd of 21.74 ml±2.71 ml; a Vdss of 74.36 ml±12.67 ml; t 1/2 a0.74 h±0.19 h; t 1/2 b 18.98 h±4.36 h; AUC = 32.75 mCi/min.ml ± 3.73 mCi/min.ml; MRT = 24.35 h±5.51 h and total clearance 3.05 ml/h±0.35 ml/h. The well-type detector fulfills the quality system requirements and the radiopharmacokinetic parameters for 99mTc-glucarate in rats are reliable.

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on complete and correct citations, reinforcing quality control through the whole journal publication chain. However, it appears that the 2010 JCR merely tallies up for each journal, all the citations made to papers published in 2008–2009, irrespective

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By use of near infrared (NIR) spectroscopy hyphenated to thinlayer chromatography (TLC) for analysis of methoxylated flavones in a phytomedicine we sought to achieve two objectives: first, to establish a method for rapid, qualitative identification of five methoxylated flavones, denoted G1, G2, G3, G4, and G5, in order of their R F values in normal-phase TLC, and, second, to produce a quantitative model for analysis of G4 (3′,4′,5′-trimethoxyflavone), the compound most representative of Primula veris flowers in phytomedicine. To provide appropriate reference analytical data for building the multivariate cluster and partial least-squares regression (PLS) model, TLC was performed on alumina with n-hexane-ethyl acetate 70:30 (v/v) as mobile phase. Forty-four spectra of eleven independent phytomedicine samples were analyzed with five scans to generate a qualitative cluster model based on PCA (principle-components analysis) that enabled differentiation between G1-G5 on the basis of their methoxylation pattern. This PLS model, in the calibration range between 0 and 1000 mg L−1, enabled quantification of G4 with a standard error of cross validation (SECV) ,54.61 mg L−1. The possibility of conducting qualitative and quantitative analysis simultaneously by use of this method revealed NIRS to be an efficient alternative to conventional modes of detection used for analysis of G1-G5, especially in phytomedicines.

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Abstract  

2-[18F]-nicotinic acid diethylamide was prepared by nucleophilic aromatic substitution in an acetamide melt of the corresponding chloro-compound and purified by high pressure liquid chromatography. Optimization of the reaction conditions led to a maximum radiochemical yield of about 50% within less than one half-life of18F. Tissue distribution of 2-[18F]-nicotinic acid diethylamide in various organs of mice showed a very fast accumulation of activity in the brain (mean body concentration MBC-239%) with a brain to blood ratio of 1.34.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: D. Bagatti, M. C. Cantone, A. Giussani, S. Ridone, C. Birattari, M. L. Bonardi, F. Groppi, A. Martinotti, S. Morzenti, M. Gallorini, and E. Rizzio

Summary  

The nuclear properties of 186gRe make it a useful agent for radionuclide therapy and imaging. The coordination compound [186gRe]Re-HEDP has proved to be a successful bone seeking agent for palliation of metastatic bone pain. Chemical, radiochemical and radionuclidic purity of commercial radiopharmaceutical [186gRe]Re-HEDP have been checked by means by γ- and β-spectrometries, INAA and paper radio-chromatography. The results indicate a good radionuclidic purity, with levels of contamination from the short-lived 188Re well below the required specifications. After injection of the radiopharmaceutical, the radiochemical measurements conducted in vivo, on biological matrices, blood, plasma and urine, have shown that, entering the systemic circulation, 186gRe dissociates from the bis-phosphonate complex as hydrosoluble [186gRe]ReO4-, and the two chemical species follow different biokinetics.

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A simple, rapid, and effective high-performance thin-layer chromatographic (HPTLC) method has been established for differentiating among the polysaccharides present in six traditional Chinese medicines (TCM), Cordyceps sinensis, Ganoderma lucidum, Astragalus memberanaceus, Panax ginseng, Panax quinquefolii , and Panax notogiseng . Acid hydrolyzates of the polysaccharides were analyzed by HPTLC with two detection reagents, aniline-diphenylamine-phosphoric acid and ninhydrin, and scanning densitometry. The compounds were separated on silica gel plates with chloroform- n -butanol-methanol-acetic acid-water 4.5:12.5:5:1.5:1.5 ( v/v ) as mobile phase. Seven monosaccharides and two glucuronic acids were used as reference compounds. The results showed that hydrolysis of polysaccharides can release specific molecules present in the herbal species in addition to the monosaccharides present. This is useful for distinguishing the origins of the polysaccharides in Chinese medicines.

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Qualitative and quantitative analysis of the organic components of composite modified double-base (CMDB) propellants have been performed by HPTLC. The method enabled analysis of a five-component mixture in less than 10 min. The relative distribution of the components of the mixture was determined by means of a UV absorbance detector capable of monitoring at several different wavelengths and of providing UV spectra which could be used to assess peak purity. Detection limits were at nanogram levels.

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Abstract  

In this study, superparamagnetic iron oxide nanoparticles (SPION) embedded by folic acid (SPION-folate) were prepared by a modified co-precipitation method. The structure, size, morphology, magnetic property and relaxivity of the SPION-folate were characterized systematically by means of XRD, VSM, HRSEM and TEM and the interaction between folate and iron oxide (Fe3O4) was characterized by FT-IR. The particle size was shown to be ≈5–10 nm. To ensure biocompatibility, the interaction of these SPION with mouse connective tissue cells (adhesive) was investigated using an MTT assay. Consequently, gallium-67 labeled nanoparticles ([67Ga]-SPION-folate) were prepared using 67Ga with a high labeling efficiency (over 96%, RTLC method) and they also showed an excellent stability at room temperature for at least 2 days and were evaluated for their biodistribution in normal rats up to 24 h compared with free Ga3+ cation and [67Ga]-SPION biodistribution. The biodistribution of the tracer among 3 other folate tracers were compared, showing lower liver uptake and higher blood circulation after 24 h leading to better bioavailability. The bone:muscle, kidney:muscle, lung:muscle, stomach:muscle ratios were 9.3, 9.32, 7.6 and 5.83 respectively. The developed folate-containing nano-system can be an interesting folate receptor tracer, capable of better cell membrane permeability while possessing paramagnetic properties for thermotherapy.

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