Nano-Dosing And Detection To Probe Neurodegenerative Disease Induced By Oligomers Of Beta Amyloid

The earliest molecular events leading to neuronal damage in neurodegenerative diseases, such as Alzheimeru0027s and Parkinsonu0027s diseases, have not been fully understood to date. One reason for this is the lack of suitable methods to dose protein aggregates locally in a controlled fashion on an individual cell and to follow the subsequent changes in cell physiology in the individual cell and neighbouring cells. We have developed a new method based on scanning ion conductance microscopy to address this issue In this work, a homemade two-nanopipette system has been developed. One nanopipette is used for nanodosing of protein aggregates of beta amyloid, the protein associated with Alzheimeru0027s disease, from the tip of a nanopippete. A second nanopipette is used as an adenosine triphosphate (ATP) sensor, fabricated at the tip of a double-barrel carbon-filled nanopipette. The operational principle of this ATP sensor is based on a Hexokinase-modified electrolyte-gated organic field-effect-transistor (EGOFET), where polypyrrole is used as the biocompatible active material, and its conductivity is increased by protonation due to ATP reactions mediated by hexokinases. Using this instrument the transient ATP release from a single astrocyte or neuron, resulting from controlled dosing of oligomers of beta amyloid to the cell, can be recorded. This should allow us to obtain new insights into the molecular mechanism of cellular damage.