Several lines of evidence point to a critical role for specific brain receptors in the pathologic process of Alzheimer's disease (AD) as well as other neurodegenerative diseases. A specific brain receptor known as metabotropic glutamate receptor (mGluR5) is considered by many to play an important mechanistic role in early AD, however this hypothesis has been exceedingly difficult to test. Major breakthroughs in clinical dementia research and drug development followed from the advent of plaque imaging agents using a medical imaging technique known as positron emission tomography (PET). In such studies, radioactive drug molecules (radiopharmaceuticals) are injected and the distributions of those molecules are measured using a PET camera. However, we still lack a means to identify and track the evolution certain receptors that precede plaque formation, a major barrier to the rapid identification of AD drug treatments that engage and modify these events. Here we propose to develop and implement novel radiochemistry procedures, in conjunction with microfluidics (lab-on-a-chip) technology, which will provide much needed tools to probe these receptors in AD and cannot be obtained by any other means. Specifically, we aim to apply these new radiopharmaceuticals to a promising new line of research aimed at detecting mGluR5 that responds to toxic events and mediate brain synapse and cell loss in AD. This work will provide an essential tool for quantitating mGluR5 toward development of new AD pharmaceuticals, and potentially to guide dosing and patient selections in the later stage of clinical trials.