The present invention relates in a first aspect to a suspension of microbubbles or microparticles in an aqueous liquid medium. Said suspension is usable for diagnostic, therapeutic and analytic purposes comprising microbubbles and/or microparticles and/or nanoparticles whereby said liquid medium contains dissolved shelf material of said microbubbles, microparticles or nanoparticles in a concentration avoiding the dissolution of said microparticles, microbubbles or nanoparticles or avoiding the loss of acoustic properties or other properties of said microbubbles, microparticles or nanoparticles. In another aspect, the present invention relates to a method for preparing a suspension containing microbubbles or microparticles in an aqueous liquid medium to achieve improved shelf life. Moreover, an aqueous liquid storage and handling solution for microbubbles or microparticles as well as for nano-particles is provided. Finally, pharmaceutical compositions containing the same are disclosed.
