Nanotechnology and Neuroscience Convergence: A Novel Tool for Neurotransmitters Monitoring

Since neurotransmitters significantly influence the brain activity, our understanding of the human brain will remain imperfect until all aspects relating to them become clear. One of the key challenges in neuroscience researches and therapies is elucidating the mechanisms by which the neurotransmitter release take place and is regulated in quantity and in time. Despite the enormous number of studies carried out to illuminate this function, efficient methods for momentary detection and visualizing these tiny neurochemicals have not been developed yet. Recent advances in nanomaterials have launched a new class of fluorescent labels by conjugating quantum dots (QDs) with biomolecules. Cadmium-based QDs have been by far the most developed in bioimaging; however, their doubtful future owing to high toxicity has turned researchers᾽ attention to more recently ternary nontoxic compounds, CuInS2. In this article a novel application of CuInS2 nanoparticles in neuroscience has been proposed. Accordingly, a newly developed synthesis method have been exploited applying refluxed procedure. The structure and surface analysis taken by TEM and FTIR analyses showed that the resulting nanocrystals have sizes ranging from 1.6 to 3.2 nm while their surface is functionalized with MPA capping ligands. Optical properties of CuInS2, demonstrating broad absorption and narrow emission spectra, 250 nm and 150 nm, respectively, with PL peak of 656 nm and FWHM 49 nm, have also been revealed by spectroscopy. All confirm that QDs are very appropriate for neurotransmitter detection in a small synaptic cleft. It is also suggested that the minimum concentration of [Cu]/[ MPA] required for complete surface coverage is 1:11.