Background: Since there is currently no cure for Alzheimer's disease (AD), it is important to develop methods that could contribute to its diagnosis and propose new therapeutic approaches for its treatment. Positron emission tomography (PET) is a medical imaging technique that can be used to diagnose Alzheimer's disease, as some radiotracers have been developed to detect amyloid plaques, one of the hallmarks of the disease. However, the radiotracers already used for the diagnosis of AD have a low half-life, which limits their use over the time and requires the presence of a cyclotron close to the examination site. The use of copper complexes could be a good alternative for the development of new radiotracers, since they can be used in PET imaging and have a longer half-life than the other radiotracers already used for AD diagnosis. Aim of the study: Design and synthesize copper complexes that could be used as PET radiotracers able to cross the blood brain barrier and detecting amyloid plaques.Material and methods: The first objective was to design a series of new copper complexes with the capacity to target amyloid plaques inside the brain and contribute to the rational synthesis of such complexes. To this end, theoretical models were used to predict the ability of the complex to cross the blood-brain barrier (BBB) which separates brain from de blood and is main gatekeeper for drugs entering the brain. The models employed consider the physicochemical properties of the molecules. Based on these models, one of the molecules was synthesized in ten steps. The key step in the synthetic strategy was the coupling of a monopicolinate-N-alkylated cyclam-based ligand with a moiety capable of recognizing Aβ plaques via a Buchwald-Hartwig coupling reaction. Potentiometric, spectrophotometric and electron paramagnetic resonance spectroscopic studies were performed to determine the structure and thermodynamic stability of the complex. In addition, the ability to target amyloid plaques was evaluated using brain sections from Alzheimer's disease patients and the cytotoxicity was evaluated using human neuronal cells.Results: A first complex has been designed and synthesized. The physicochemical studies performed indicate that this complex seem to be thermodynamically stable. In addition, cytotoxicity tests on human neuronal cells indicate low toxicity and labeling tests on brain sections from Alzheimer's patients suggest that the complex is capable of recognizing amyloid plaques. Conclusion: We have developed a novel copper complex that is able to detect recognize amyloid plaques. In the future this molecule could be used in PET and contribute to the diagnosis of Alzheimer's disease. From these results, we also propose to develop a new copper complex for tau PET imaging.