The interplay of long-ranged Coulomb interactions with branched topology leads to a number of distinctive features in conformations of branched polyelectrolytes in aqueous solutions, as compared to those of linear polyelectrolytes. We discuss conformations of branched ionic macromolecules with diverse topologies (star- or comb-like, regular dendritically or randomly branched) in aqueous solutions, with the main emphasis on conformational transitions triggered in such macromolecules by variation in environmental conditions (temperature, pH, ionic strength of the solution). Interactions and complexation of branched macroions with oppositely charged polyelectrolytes and nanocolloids are addressed as well. The predictions of the analytical Poisson-Boltzmann theory are compared to the result of numerical self-consistent field modelling, molecular dynamics and Monte Carlo simulations.
