5.1 This practice is applicable to the separation of specific radionuclides of interest as part of overall radiochemical analytical methods. Radionuclides of interest may need to be quantified at activity levels of less than 1 Bq. This may require measurement of less than 1 fg of analyte in a sample which has a mass of a gram to more than several kilograms. This requires concentration of radionuclides into a smaller volume counting geometry or exclusion of species which would impede subsequent chemical separations, or both. MnO₂ has shown good selectivity in being able to concentrate the following elements: actinium (Ac), bismuth (Bi), lead (Pb), polonium (Po), plutonium (Pu), radium (Ra), thorium (Th), and uranium (U) as noted in the referenced literature (see Sections 4 and 8). The MnO₂ can be loaded onto a variety of substrates in preparation for use or generated in-situ in an aqueous solution. The presented processes are not meant to be all encompassing of what is possible or meant to address all limitations of using MnO₂. Some limitations are noted in Section 6, Interferences.

1.1 This practice is intended to provide a variety of approaches in which manganese oxide (MnO₂) can be used to concentrate radionuclides of interest into a smaller volume counting geometry or exclude other species that would otherwise impede subsequent chemical separation steps in an overall radiochemical method, or both.

1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.