“…This ideal time is when the 10 B concentration in tumour is higher than the concentration in blood and surrounding healthy tissues to prevent damage to these regions. Previous studies carried out in order to estimate brain-to-blood (Br:Bl), T:Br and T:Bl 10 B concentration ratios using kinetic models (Ryynanen et al, 2000; and Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) (Laakso et al, 2001) techniques, gave different results. Up to now several techniques (Wittig et al, 2008b) have been used to determine the spatial distribution and pharmacokinetics of 10 B agents (Elowitz et al, 1998;Ryynanen et al 2000, Laakso et al, 2001, Kabalka et al, 2003, Wang et al, 2004.…”