Iodine delivery rate

Iodinated nonionic dimers iodixanol, iode-col, iofratol, and iotrol (or iotrolan) have respectively lower osmolalities (200, 320, 140, and 320 mOsm/kg HgO) and higher viscosities (8.7, 7.2, 8.5, and 8.1 mPa-s at 37°C) than those of iodinated nonionic monomers. Felder and de Haen (429) found unexpectedly that solution mixtures of iodinated nonionic monomers and dimers, such as iomeprol and iofratol, have a lower toxicity and a lower viscosity than those of either of the components and can supply a favorable iodine delivery rate through less invasive catheters during the injection, but have an intermediate osmolality compared to that of the pure solutions of the monomer and dimer components. 

Generally speaking, a moderate to high iodine delivery rate (IDR) is needed for CTA of the chest. Therefore, 1.5-2.0 g iodine/s should be administered intravenously. The contrast medium delivery has to be maintained for a longer time, as an opacification of the pulmonary circulation and the systemic circulation is needed at the same time. Dual-head power injectors, individual adaptation of the contrast delivery... 

Knollmann F, Schimpf K, Felix R (2004) [Iodine delivery rate of different concentrations of iodine-containing contrast agents with rapid injection]. Rofo 176 880 884... 

The distribution rates for iodination of monosubstituted benzene derivatives have been reported. Under conditions of thermodynamic control (elevated temperature), meta substitution is observed. Under conditions of kinetic control (room temperature), a significant preference for para substitution is observed for compounds containing oriha- puru-directing substituent groups. Ortho substitution results when chelation of TTFA with the directing substituent permits intramolecular delivery of the electrophile. For example, methyl benzoate gives almost exclusively or/ho-lhallation (95%). 

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