. | . |
Zn-InsP6 complex can enhance excretion of radioactive strontium from the body by Staff Writers Kanazawa, Japan (SPX) Jun 04, 2018
90Sr (t1/2 = 29.1 y) is one of the most important nuclear fission elements. After the nuclear power plant disasters of Chernobyl and Fukushima Daiichi, 90Sr was released into the atmosphere and the ocean. 90Sr is harmful to humans because 90Sr has a long half-life, and its daughter radionuclide, 90Y (t1/2 = 64.1 h), emits high-energy beta particles. It has been reported that internal exposure to 90Sr could be associated with the development of leukemia and osteosarcoma. Therefore, compounds inhibiting the absorption of radiostrontium from the gastrointestinal tract into the bloodstream and enhancing its elimination after intake can decrease the absorbed radiation dose of people exposed to radiostrontium. Indeed, basic research has shown that alginate can promote the excretion of 90Sr. Myo-inositol-hexakisphosphate (phytic acid: InsP6) is a natural compound that abounds in plants, especially in whole grains, cereals, legumes, seeds, and nuts. Due to its structure, InsP6 exhibits high chelation potential with many kinds of metal cations. Recently, we prepared complexes of InsP6 with zinc or lanthanum ions (Zn-InsP6 and La-InsP6, respectively) and evaluated them as radiocesium decorporation agents, because both complexes are insoluble in water and are spacious enough to potentially accommodate additional metal cations coordinated by chelation. In fact, InsP6 is soluble in water, but chelation with zinc or lanthanum ions decreases the solubility in water, and thereby reduces the absorption in the intestinal tract. In this study, we hypothesized that Zn-InsP6 and La-InsP6 can work as 90Sr decorporation agents and evaluated their potential in vitro and in vivo. Experiments using normal mice were performed to evaluate the influence of Zn-InsP6 on the biodistribution of radiostrontium. In these experiments, we replaced 90Sr with 85Sr (T1/2 = 64.8 d) because 85Sr emits gamma rays, which are easy to measure.
The Results These data meet the requirements of the Langmuir adsorption model, indicating the correctness of the assumption that the adsorbate acts as a uniform surface with finite identical binding sites characterized by monolayer adsorption of the adsorbate. The maximum sorption capacity of Zn-InsP6 and La-InsP6 was estimated as 133.7 and 6.4 mg Sr/g, respectively. To evaluate whether Zn-InsP6 can enhance the elimination of 85Sr from the body in vivo, 85SrCl2 was orally administrated to mice just after oral administration of Zn-InsP6 suspension. As the results, pretreatment with Zn-InsP6 significantly decreased the accumulation of radioactivity in the bone and the blood after oral administration of 85SrCl2. These results indicate that Zn-InsP6 inhibited the absorption of 85Sr2+ from the intestine into the bloodstream and enhanced the excretion of 85Sr2+ in the feces.
Significance and future prospects We suppose that the Zn-InsP6 complex could improve the biodistribution of some radiopharmaceuticals and decrease the unnecessary radiation dose of patients, and it is currently under investigation.
New material detects the amount of UV radiation and helps monitor radiation dose Turku, Finland (SPX) May 23, 2018 UV radiation is known to cause many skin and eye diseases such as cancer. Therefore, it is essential to have a simple method for detecting the quantity and quality of UV radiation from, for example, the Sun. This is currently achieved by using mainly organic molecules that change colour under UV radiation. The downside of using these molecules, however, is their poor durability which is due to the fact that the colour changes involve reorganisation of the molecular structure. Organic molecul ... read more
|
|
The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us. |