Facile synthesis of boronic acid-functionalized magnetic nanoparticles for efficient dopamine extraction

Because dopamine (DA) is one of the most critical neurotransmitters that influence a wide variety of motivated human behaviors, it is necessary to develop a facile diagnostic tool that can quantify the physiological level. In this study, core–shell magnetic silica nanoparticles (Fe(3)O(4)@SiO(2)) were prepared using a modified sol–gel reaction. The Fe(3)O(4)@SiO(2) were functionalized using 3-aminophenylboronic acid (APBA) via a facile and rapid synthetic route, hereafter referred to as Fe(3)O(4)@SiO(2)@APBA The resultant Fe(3)O(4)@SiO(2)@APBA not only adsorbed DA molecules, but also were easily separated from solution using a simple magnetic manipulation. The adsorbed amounts of DA by the Fe(3)O(4)@SiO(2)@APBA were quantified by measuring the changes in fluorescence intensity of polydopamine (at 463 nm) originated from the self-polymerized DA remained in the supernatant before and after the adsorption process. The Fe(3)O(4)@SiO(2)@APBA exhibited two-stage adsorption behavior for DA, and the maximal adsorption capacity was 108.46 μg/g at pH 8.5. Our particle system demonstrated the potential application for extracting compounds with cis-diols (including catechol amines) from the biological fluid. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s40580-019-0200-7) contains supplementary material, which is available to authorized users.