Perfluorooctyl bromide

The first heavier than water internal tamponade was introduced in 1987 by Chang with LPFC [1]. The two perfluorocarbons most used are perfluorooctane and perfluorodecaline. Perfluorotributylamine, perfluoropolyether, perfluorooctyl-bromide and perfluorophenanthrene are less used. LPFC are transparent fluids and are not miscible in water and their main characteristic is their high density (1.76-2.03) [2], Their properties are summarised in Table 1. 

PESDA, AI-700, MP 1950) and of perfluorooctyl bromide (liquivent and perflexane) are under clinical development (Figure 8.93). 

Perfluorooctyl bromide is being used very successfully to enhance the contrast between healthy and diseased tissue in H MRl procedures and as a general imaging agent for X-ray and other forms of examination of soft tissue. 

Using a fluorous palladacycle catalyst 10 originating from the corresponding fluorous Schiff base and palladium acetate, a fluorous Mizoroki-Heck reaction was achieved with an excellent turnover number (Scheme 12). A homogeneous catalytic reaction system was obtained when DMF was used as the solvent. After the reaction, perfluorooctyl bromide was added to facilitate the separation of DMF (containing the products and amine salts) from the catalyst phase. The resulting lower fluorous layer was condensed under vacuum and the catalyst residue was used in a second run. In this reaction, the palladacycle catalyst appears to act as a source of palladium nanoparticles, which are thought to be the dominant active catalyst. 

Typical fluorinated solvents are perfluorodimethylcyclohexane, trifluoromethyl-cyclohexane, perfluorodecalin, perfluorooctyl bromide (Perflubron, Imagent), l//-perfluorooctane, and Hostinert 216 (Figure 7.8). 

Diou O, Tsapis N, Giraudeau C, Valette V, Gueutin C, Bourasset F. Long-circulating perfluorooctyl bromide nanocapsules for tumor imaging by FMRI. Biomaterials 2012 33 5593-602. 

Experiments confirm the decrease in the ripening rate on addition of a poorly soluble component to the dispersed phase. Buscall et alP examined emulsions of SDS after adding long chain alkanes. Kabal nov et al showed that eqn. (1.22) was well obeyed for emulsions of SDS and hexane to which small quantities of the alkanes octane to hexadecane were added. Recently, Weers and Arlauskas have provided the first experimental evidence that molecular diffusion in two-component mixtures leads to an increase in the mole fraction of the less soluble component in the smaller drops. Using the technique of sedimentation field-flow fractionation coupled with gas chromatography, the disperse phase composition can be determined for monosized drop fractions. Evidence is also provided for the development of bimodal distributions at low volume fractions of the less soluble component, in excellent agreement with the above predictions. Their system was perfluorooctyl bromide (plus perfluorododecyl bromide) as oil stabilised by egg yolk phospho-lipid.2 ... 

A strong dependence on volume fraction has been observed for fluorocarbon-in-water emulsions. For example, Ni et al, found a ca. three-fold increase in or in going from tp — 0.08 to 0.52 for concentrated emulsions of perfluorooctyl bromide. Trevino et al. also observed the dependence of o) on , and in addition verified the cubic scaling and time independence of the distribution function for similar concentrated perfluorooctyl bromide emulsions. ... 

A second-generation fluorochemical emulsion, Oxygent , contains 60% (w/v) perfluorooctyl bromide stabilized with egg-yolk lecithin [93]. This emulsion can be stored without freezing and the organ half-time is 4 days. 

Meinert et al. [104-106] found that already small quantities [1 or 2% (w/v)] of partially fluorinated alkanes, C, F2 ,+ iC H2h+i, stabilize perfluorodecalin-Pluronic F68 emulsions. Riess et al. [130] deseribed a binary emulsifier system, consisting of a nonfluorinated surfactant in conjunction with a partially fluorinated alkene. Riess et al. [130] named the fluorinated amphiphile a dowel," suggesting that its fluorophilic end adsorbs in the fluorocarbon surface and its lipophilic end penetrates the lipophilic part of the egg-yolk phospholipid. The dowel, C8Fi7CH=CHCsHi7, increased the stability of a perfluorooctyl bromide (PFOB)-egg-yolk lipid emulsion stability considerably. The droplet size (0.25, m) remained constant over 9 months, even at 40 C. In the absence of the dowel, the droplet size more than doubled at 25 C to 0.49 jum. 

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