Determination of radionuclides in samples of middle-aged and older human femurs

Rapid 90Sr quantification method based on the Bateman equation for routine laboratory work

“…Thus, yttrium is transferred to the organic phase, while strontium remains in the aqueous phase . Yttrium is then back-extracted with 25% ammonia solution to form Y(OH) 3 [9,11]. Finally, Y(OH) 3 dissolves in the nitric acid, and yttrium is precipitated as an oxalat e [11,12] and then further purifi ed on ion exchange resin [11].…”

“…Yttrium is then back-extracted with 25% ammonia solution to form Y(OH) 3 [9,11]. Finally, Y(OH) 3 dissolves in the nitric acid, and yttrium is precipitated as an oxalat e [11,12] and then further purifi ed on ion exchange resin [11]. An alternative technique is to co-precipitate interfering radioisotopes with barium chromate, while 90 Y is precipitated as Y(OH) 3 [9,13].…”

“…Challenges related to 90 Sr analysis include the presence of calcium in the matrix, overlapping 90 Sr, 90 Y and 89 Sr -spectra, and the required separation of other radionuclides [7,8,11]. These diffi culties can be resolved by focusing on either 90 Y separation and immediate radioactivity measurements, or 90 Sr separation and waiting for secular equilibrium, at which point, half of the measured radioactivity originates from 90 Sr.…”

“…It is worth to point that elutes which here are considered as waste contain 90 Y which could be used for 89 Sr and 90 Sr calculation as described in Eqs. (10) and (11). This allows to calculate the results much quicker in comparison to methods which require 90 Sr/ 90 Y equilibrium.…”

“…( 11) where t 89 is the time from start to the midpoint of the activity measurement and t Y is the time from yttrium separation to the midpoint of activity measurement, A Sr+Y is the sum of 90 Sr and 90 Y activities and A Y1 is 90 Y activity measured after its ingrowth. This approach is described in detail in [18]: (11)…”