An Optimized Protocol for the Efficient Radiolabeling of Gold Nanoparticles by Using a <sup>125</sup>I-labeled Azide Prosthetic Group

Here, we demonstrate a detailed protocol for the radiosynthesis of a 125I-labeled azide prosthetic group and its application to the efficient ...

Korea Atomic Energy Research Institute

Much attention is recently gained for Elsholtzia splendens extracts and issue on their usage is raised due to their biological properties. However, there is no sufficient background information on toxicological evaluation of E. splendens extracts to give an assurance of safety for developing dietary supplements and functional foods. The objective of this study was to evaluate safety on E. splendens extracts using acute oral toxicity, bacterial reverse mutation, and chromosome aberration test. Total flavonoids within E. splendens were extracted with 80% of methanol by a reflux condenser. Both female and male mice were orally administrated E. splendens extracts at the dose of 0, 500, 1000, and 2000 mg/kg body weight/day. Mutagenicity of the extracts was evaluated in a bacterial reverse mutation assay using histidine requiring Salmonella typhimurium (TA 98, TA 100, TA 1535, and TA 1537) and tryptophan-requiring Escherichia coli (WP2uvrA). In vitro chromosome aberration assay in Chinese Hamster Lung (CHL) was conducted to evaluate genotoxicity. Single administration of dose levels of 500, 1000, and 2000 mg/kg body weight/day to mice for 15 days did not produce any significant mortality, clinical signs, body weight loss, and gross findings. E. splendens extracts in the range of 156.3-5000 microg/plate did not induce mutagenicity in S. typhimurium and E. coli with and without metabolic activation system. Any significant chromosomal aberration was not observed in CHL cells 6h after treating with the extract at the concentrations of 1250, 2500, and 5000 microg/mL in absence and presence of metabolic activation system. However, frequency of chromosomal aberration in 22 h after treatment without metabolic activation system was increased with showing a pattern of dose-response relationship. The highest concentration of 5000 microg/mL significantly induced chromosomal aberration. E. splendens extracts may induce chromosomal structure abnormality in CHL cells. This study suggests that further study is needed to assess the potential genotoxic effects of E. splendens extracts.

Safety evaluation of Elsholtzia splendens extracts: assessment of acute toxicity and mutagenicity.

The present study was designed to evaluate the radioprotective effect of hesperidin, a citrus flavanoglycone, against γ-radiation-induced cellular damage in the liver, heart, and kidney of rats. Whole-body γ-radiation exposure (5 Gy) of healthy adult rats resulted in cellular damage and oxidative stress manifested as increased levels of serum marker enzymes, lipid peroxidation, and fibrosis in the tissues, accompanied by depletion of cellular glutathione and abnormal alteration in the levels of lysosomal enzymes. Treatment with hesperidin (50 and 100 mg/kg, p.o.) for 7 days was found to offer significant protection against γ-radiation-induced toxicity in the tissues, which was evident by the improved status of most of the parameters investigated. Further, the histological examination of periodic acid-Schiff-stained tissue sections of animals treated with hesperidin following radiation exposure showed minimal necrotic damage with a recovery pattern in a dose-dependent manner compared with radiation-exposed animals. The results of our study show that administration of hesperidin offers effective protection against γ-radiation-induced cellular damage and oxidative stress in rats.

Protective effect of hesperidin, a citrus flavanoglycone, against γ-radiation-induced tissue damage in Sprague-Dawley rats.

Gemcitabine-loaded TSL (Gem-TSL) was used in combination with hyperthermia (HT) to treat the colon adenocarcinoma-bearing BALB/c mice for improved anticancer effect following intravenous administration.

Enhanced antitumor efficacy of gemcitabine-loaded temperature-sensitive liposome by hyperthermia in tumor-bearing mice.

Herein we report the radiosynthesis of a pyridine derived azide prosthetic group for iodine radioisotope labeling of dibenzocyclooctyne (DBCO) conjugated molecules. The radiolabeling of the stannylated precursor 2 was conducted using [(125)I]NaI and chloramine-T to give (125)I-labeled azide ([(125)I]1) with high radiochemical yield (72±8%, n=4) and radiochemical purity (>99%). Using (125)I-labeled azide ([(125)I]1), cyclic RGD peptide and near infrared fluorescent molecule were efficiently labeled with modest to good radiochemical yields. The biodistribution study and SPECT/CT images showed that [(125)I]1 underwent rapid renal clearance. These results clearly demonstrated that [(125)I]1 could be used as an useful radiotracer for in vivo pre-targeted imaging as well as efficient in vitro radiolabeling of DBCO containing molecules.

Synthesis and evaluation of an (125)I-labeled azide prosthetic group for efficient and bioorthogonal radiolabeling of cyclooctyne-group containing molecules using copper-free click reaction.

This study investigated the degree to which instrumental measurements explain the variation in pork loin tenderness as assessed by the sensory evaluation of trained panelists. Warner-Bratzler shear force (WBS) had a significant relationship with the sensory tenderness variables, such as softness, initial tenderness, chewiness, and rate of breakdown. In a regression analysis, WBS could account variations in these sensory variables, though only to a limited proportion of variation. On the other hand, three parameters from texture profile analysis (TPA)-hardness, gumminess, and chewiness-were significantly correlated with all sensory evaluation variables. In particular, from the result of stepwise regression analysis, TPA hardness alone explained over 15% of variation in all sensory evaluation variables, with the exception of perceptible residue. Based on these results, TPA analysis was found to be better than WBS measurement, with the TPA parameter hardness likely to prove particularly useful, in terms of predicting pork loin tenderness as rated by trained panelists. However, sensory evaluation should be conducted to investigate practical pork tenderness perceived by consumer, because both instrumental measurements could explain only a small portion (less than 20%) of the variability in sensory evaluation.

Estimation of Sensory Pork Loin Tenderness Using Warner-Bratzler Shear Force and Texture Profile Analysis Measurements.

In this report, we present a rapid and highly efficient method for radioactive iodine labeling of trans-cyclooctene group conjugated biomolecules using inverse-electron-demand Diels-Alder reaction. Radioiodination reaction of the tetrazine structure was carried out using the stannylated precursor 2 to give (125)I-labeled azide ([(125)I]1) with high radiochemical yield (65±8%) and radiochemical purity (>99%). For radiolabeling application of [(125)I]1, trans-cyclooctene derived cRGD peptide and human serum albumin were prepared. These substrated were reacted with [(125)I]1 under mild condition to provide the radiolabeled products [(125)I]6 and [(125)I]8, respectively, with excellent radiochemical yields. The biodistribution study of [(125)I]8 in normal ICR mice showed significantly lower thyroid uptake values than that of (125)I-labeled human serum albumin prepared by a traditional radiolabeling method. Therefore [(125)I]8 will be a useful radiolabeled tracer in various molecular imaging and biological studies. Those results clearly demonstrate that [(125)I]1 will be used as a valuable prosthetic group for radiolabeling of biomolecules.

Highly efficient method for (125)I-radiolabeling of biomolecules using inverse-electron-demand Diels-Alder reaction.

This study aimed to determine bioactive components and radical scavenging capacity of black raspberry seed extracts as byproducts obtaining during the juice (FSE) and wine (WSE) making process. Cyanidin-3-O-rutinoside was identified as a major anthocyanin and the total anthocyanin contents of fresh and wine seed were 78.24 and 41.61 mg/100 g of dry weight, respectively. The total phenolic and flavonoid contents of FSE and WSE were 2.31 g gallic acid equivalent (GAE) and 360.95 mg catechin equivalent (CE), and 2.44 g GAE and 379.54 mg CE per 100 g dry weight, respectively. The oxygen radical absorbance capacity (ORAC) values were 1041.9 μM TE/g for FSE and 1060.4 μM TE/g for WSE. Pretreatment of the FSE and WSE inhibited the generation of intracellular reactive oxygen species (ROS), DNA and protein damage induced by hydroxyl radicals, and Fe(3+)/ascorbic acid-induced lipid peroxidation in a dose dependent manner. WSE more effectively protected from oxidative damage than FSE. Results from the current study suggest that black raspberry seeds as byproducts from juice and wine processing could be potential sources for natural antioxidants.

Mi Hee Choi

Advanced Radiation Technology Institute

Korea Atomic Energy Research Institute

An Optimized Protocol for the Efficient Radiolabeling of Gold Nanoparticles by Using a ¹²⁵I-labeled Azide Prosthetic Group

Mi Hee Choi

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Advanced Radiation Technology Institute

Korea Atomic Energy Research Institute

An Optimized Protocol for the Efficient Radiolabeling of Gold Nanoparticles by Using a 125I-labeled Azide Prosthetic Group

Advanced Radiation Technology Institute

An Optimized Protocol for the Efficient Radiolabeling of Gold Nanoparticles by Using a ¹²⁵I-labeled Azide Prosthetic Group