Novel ultrasound contrast agents

摘要

New ultrasound contrast agents that comprise microbubbles encapsulating a gas within a shell made from a blend of bipolar compounds having mixed carbon chain length. The compounds have hydrophobic groups selected from the group consisting of straight-chained alkyls, alkylethers, alkylthiolethers, alkyldisulfides, polyfluoroalkyls, and polyfluoroalkylethers having a carbon chain length greater than or equal to 16 and less than or equal to 32. The polar groups are connected to the hydrophobic groups by means of a linker. The polar head groups are selected from the group consisting of CO₂-M⁺, SO₃^-M⁺, SO₄^-M⁺, PO₃^-M⁺, PO₄^-M⁺₂, N(R)₄⁺, a pyridinium or substituted pyridinium group, and a zwitterionic group; R is selected from the group consisting of -H, -CH₃, alkyl, cycloalkyl, substituted cycloalkyls containing one or more heteroatoms, and benzyl and can be the same or different; and Z' is a nonionic and M is a cation.