Search Results
Abstract
Biodistribution of EDTA derivatives99mTc-Sn-DOTA, DDDTA, DHDTA /1,2-dinitriloalkane-tetraacetic acids/ individually and bound to liposome in rats is described. The obtained results are compared with99mTc-Sn-EDTA.
Abstract
99mTc-labelled methionine was prepared by ligand substitution reaction. Methionine was reacted with99mTc-citrate under physiological conditions, to form a radiochemically pure, neutral Tc complex. Labelling parameters involving incubation period of methionine in99mTc-citrate solution were studied by paper and thin-layer chromatography.
Abstract
Carboxymethyl chitosan, (CMC), and N-lauryl-carboxymethyl chitosan (LCMC), have been prepared as water soluble derivatives of chitosan. These biodegradable chitosan derivatives were characterized and investigated for nuclear imaging and body distribution. They were labeled with 99mTc to use them as targeted delivery to some organs in vivo for nuclear imaging and to follow their biodistribution within the body. The factors controlling the labeling efficiency have been investigated. The percent labeling yield was determined by using ascending paper chromatographic technique. In vivo biodistribution studies of radiolabeled chitosan derivatives were carried out in groups of female Wistar rats, the body distribution profile in rat was recorded by gamma scintigraphy and the biodistribution of 99mTc-labeled compounds in each organ was calculated as a percentage of the injected dose per gram of tissue (%ID/g). It has been found that the biodistribution of the two compounds and the pattern of their liver uptake were markedly different. The present study demonstrates a high potential approach for liver imaging using 99mTc-LCMC. An intriguing finding of this study was that the three samples were excreted rapidly via the kidneys because of the water-soluble nature of chitosan derivatives. This suggests that water-soluble chitosan derivatives are good polymeric carriers for radioactive element that overcomes accumulation in the body. Moreover, the easy and inexpensive availability of chitosan could be beneficial for applications in scintigraphic imaging.
Abstract
The self life of the freeze-dried formulation kits utilized for the preparation of the new bone imaging radiopharmaceutical99mTc-1,2-dihydroxy-1,2-bis/dihydroxyphosphinyl/ethane /99mTc-DHPE/ has been investigated as well as the toxicity of the DHPE. In a biodistribution investigation of99mTc-DHPE in rats, in comparison to99mTc-methylenediphosphanate /99mTc-MDP/,99mTc-DHPE exhibited a certain extent higher skeleton uptake, a higher blood clearance rate, a very low concentration in other organs, a satisfactory biological stability and excretion primarily through the kidneys. These properties demonstrate that99mTc-DHPE is a new promising skeleton imaging radio-pharmaceutical.
ligand 99 mTc-MIP-1404 for whole-body primary staging of patients with prostate cancer. Clin Nucl Med. 2018; 43: 225–231. 20 Perera M, Papa N, Christidis D, et al. Sensitivity, specificity
Abstract
The possible effects of several protecting procedures on the quality of99mTc eluates were investigated. The content of99Mo in the eluates (99Mo breakthrough) was expressed in (%) with respect to the total adsorbed99Mo radioactivity and in (
) i.e. as the ratio of99Mo and99mTc radioactivities in each particular eluate. The radiochemical purity was expressed in (%) of99mTc(VII) in the eluates. The content of Al3+ and Cu2+ as chemical impurities was also determined.
Abstract
This paper addresses the development of two new radiopharmaceuticals for infection imaging. The optimization of the labeling yield of ciprofloxacin analogous, lomefloxacin and ofloxacin, with 99mTc is described. 99mTc-lomefloxacin was obtained with a radiochemical yield of 93.6% by adding 99mTc to 2.5 mg lomefloxacin in the presence of 50 μg SnCl2 while 99mTc-ofloxacin was obtained (96.6%) by adding 99mTc to 2 mg ofloxacin in the presence of 50 μg SnCl2. Biodistribution studies in rats were carried out in experimentally induced infection in the left thigh using Staphylococcus aureus. Both thighs of the rats were dissected and counted and the ratio of bacterial infected thigh/contralateral thigh was then evaluated. 99mTc-lomefloxacin showed higher uptake (T/NT = 6.5±0.5) in the infectious lesion than 99mTc-ofloxacin (T/NT = 4.3±0.6) and abscess-to-muscle ratios for both preparations were higher than that of 99mTc-ciprofloxacin (T/NT = 3.8±0.8), indicating that 99mTc-lomefloxacin could be used for infection imaging.
Abstract
The purpose of this work was to label polyclonal antibodies with99mTc such as photoactivated IgG and to check the radiochemical and biological behavior of the labeled product. Experiments were carried out to found the formulation of optimal binding of99mTc to polyclonal IgG. In addition animal studies in normal mice and in mice bearing a promoted inflammation foci were performed. The labeled product was analyzed by size-exclusion HPLC and ITLC. Higher amount than 23μg of tin per 500μg of protein gave between 87% and 93% labeling. Protein concentrations between 1.5 and 5 mg/ml gave 90% labeling yields.
Abstract
The aim of this work is the development of new radiopharmaceuticals for imaging infection and inflammation in human. Gatifloxacin (fluoroquinolone derivative) and cefepime (cephalosporine derivative) are antibiotics used to treat bacterial infections were investigated to label with one of the most important radioactive isotopes (technetium-99m). The reaction parameters that affect the labeling yield such as substrate concentration, stannous chloride dihydrate concentration, pH of the reaction mixture, and reaction time were studied to optimize the labeling conditions. Maximum radiochemical yield of 99mTc–gatifloxacin (90 ± 1.8%) complex was obtained by using 50 μg SnCl2·2H2O and 2.5 mg gatifloxacin at pH 10 while 99mTc–cefepime was prepared at pH 8 with a maximum radiochemical yield of 98 ± 1.4% by adding 99mTc to 5 mg cefepime in the presence of 50 μg SnCl2·2H2O. Biological distribution of 99mTc–gatifloxacin and 99mTc–cefepime was carried out in experimentally induced infection rats, in the left thigh, using Escherichia coli. Both thighs of the rats were dissected and counted and the ratio of bacterial infected thigh/contralateral thigh was then evaluated. T/NT for both 99mTc–gatifloxacin and 99mTc–cefepime was found to be 4.5 ± 0.3 and 8.4 ± 0.1, respectively, which was higher than that of the commercially available 99mTc–ciprofloxacin. The abscess to normal muscle ratio indicated that 99mTc–cefepime could be used for infection imaging. Besides, in vitro studies showed that 99mTc–cefepime can differentiate between bacterial infection and sterile inflammation.
Abstract
A modified sorbent for99mTe generators of higher activities has been developed. The sorbent consists of two layers. The layer in which (F.P.)99Mo is adsorbed contains alumina and silica gel mixture in the weight ratio 40
60%. The underlaying layer contains 0.5% g of pure alumina. The performances of the columns filled with this sorbent are compared to these containing pure alumina with respect to the total elution efficiency of99mTc and the elution efficiency ratio of subsequent elutions. Radiochemical and radionuclidic purities (99Mo breakthrough) of eluates from both kinds of columns have also been determined and compared.
