Probing the interior of synaptic vesicles with internalized nanoparticles.

Synaptic vesicles are subcellular organelles that are found in the synaptic bouton and are responsible for the propagation of signals between neurons. Synaptic vesicles undergo endo- and exocytosis with the neuronal membrane to load and release neurotransmitters. Here we discuss how we utilize this property to load nanoparticles as a means of probing the interior of synaptic vesicles. To probe the intravesicular region of synaptic vesicles, we have developed a highly sensitive pH-sensing polymer dot. We feel the robust nature of the pH-sensing polymer dot will provide insight into the dynamics of proton loading into synaptic vesicles.