We report the first application of a high-pressure electrochemical strategy to study heterogeneous charge transfer (CT) in a room-temperature ionic liquid, [BMIM][BTA]. High-pressure kinetic studies on electron exchange for two redox couples of different charge type, viz. [Fe(bipy)3]3+/2+ and [Fe(cp)2]+/0, at bare Au electrodes within the range of 0.1-150 MPa, revealed large positive volumes of activation that were found to be virtually the same for the two redox couples in terms of the CT rate constants and diffusion coefficients, despite the reactant's charge type. Independent viscosity (fluidity) studies at elevated pressure (up to 175 MPa), were also performed and revealed a pressure coefficient closely resembling the former ones. Complementary temperature-dependent kinetic studies within the range of 298-358 K also revealed the virtual similarity in activation enthalpies for the same kinetic and diffusion processes, as well as the viscosity of [BMIM][BTA]. A rigorous analysis of the complete variety of obtained results strongly indicates that dynamic (frictional) control of CT is operative by way of the full adiabatic mechanism. The contribution of the Franck-Condon term to the activation free energy of the kinetic process seems almost diminished because of the high value of electronic coupling and freezing out of the outer-sphere reorganization energy. Further analyses indicate that frictional control most probably takes place through slow translational modes (implying "minimal volume" cooperative dislocations) of constituent ions. This kind of motion seems further slowed down within the vicinity of the active site presumably located within the diffusive-like zone situated next to the compact (first) part of the metal/ionic liquid junction.

Dosimetric results in treatments of neuroblastoma and neuroendocrine tumors with (131)I-metaiodobenzylguanidine with implications for the activity to administer.MINGUEZ GABINA, PABLO; Flux, Glenn; Genolla, Jose; Guayambuco, Sonia; Delgado, Alejandro; Fombellida, Jose Cruz; Sjögreen Gleisner, Katarina , Flux, G., Genolla, J., Guayambuco, S., Delgado, A., Fombellida, J. C., & Sjögreen Gleisner, K. (2015). Dosimetric results in treatments of neuroblastoma and neuroendocrine tumors with (131)I-metaiodobenzylguanidine with implications for the activity to administer. Medical Physics, 42(7), 3969-3978. DOI: 10.1118/1.4921807General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.• Users may download and print one copy of any publication from the public portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Methods: Nine NB patients and six NET patients were included, giving in total 19 treatments as four patients were treated twice. Whole-body absorbed doses were determined from doserate measurements and planar gamma-camera imaging. For six NB and five NET treatments, red-marrow absorbed doses were also determined using the blood-based method.Results: Dosimetric data from repeated administrations in the same patient were consistent. 30In groups of NB and NET patients, similar whole-body residence times were obtained, implying that whole-body absorbed dose per unit of administered activity could be reasonably well described as a power function of the patient mass. For NB, this functional form was found to be consistent with dosimetric data from previously published studies. The whole-2 body to red-marrow absorbed dose ratio was similar among patients, with values of 1.4±0.6 to 35 1.7±0.7 (1 standard deviation) in NB treatments, and between 1.5±0.6 and 1.7±0.7 (1 standard deviation) in NET treatments. Conclusions:The consistency of dosimetric results between administrations for the same patient supports prescription of the activity based on dosimetry performed in pre-treatment studies, or during the first administration in a fractionated schedule. The expressions obtained 40 for whole-body absorbed doses per unit of administered activity as a function of patient mass for NB and NET treatments are believed to be a useful tool to estimate the activity to administer at the stage when the individual patient biokinetics has not yet been measured.

Simple and consistent procedures for SPECT/CT based whole-volume and maximum-voxel dosimetry have been described, both based on experimentally determined recovery coefficients. Generally the results from the two approaches are consistent, although there is a small, systematic difference in the absorbed dose due to differences in the S-values, and some variability due to differences in the estimated effective half-lives, especially when the effective half-life is long. Irrespective of the method used, the patient absorbed doses obtained span over two orders of magnitude.

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