Molecular imaging of glioblastoma cells using functionalized nanorods and a high resolution optoacoustic microscope

Optoacoustic imaging has been intensively investigated in the last decade in the preclinical imaging research community. In addition of combining high contrast and high resolution, this modality features the advantage of enabling molecular imaging. When combined with suitable contrast agents such as dyes, gold nanoparticles or single-wall carbon nanotubes that are coupled to specifically binding moieties, optoacoustic imaging allows localizing of tissue structures based on their specific molecular signature. This has been proven in various proof-of-concept in-vivo experiments involving different kinds of optoacoustic imaging systems and diseases models. However, for a deeper understanding of the processes involved in optoacoustic molecular imaging (i.e. the binding of the targeted contrast agents to single cells), the phenomena have to be studied on the cellular level. For this purpose, we developed an optoacoustic microscope for high resolution imaging of cells and cell-contrast agent interactions. Using a glioblastoma cell model and chlorotoxin-functionalized nanoparticles, we performed proof-of-concept experiments showing that the approach of molecular optoacoustic imaging can be transferred from in-vivo to the single cell level.