The synthesis of PEI core@silica shell nanoparticles and its application for sensitive electrochemical detecting mi-RNA

• Published in: Talanta (Oxford) Vol. 198; pp. 534 - 541
• Main Authors: Gong, Dandan, Hui, Xiaoning, Guo, Zhihui, Zheng, Xingwang
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.06.2019
• Subjects: Differential pulse voltammetry; DNA probe; High capacity; mi-RNA detection; PEI/Cu2+/SiO2 NPs; PEI/Cu2+/SiO2 NPs; High capacity; DNA probe; Differential pulse voltammetry; mi-RNA detection; PEI/Cu(2+)/SiO NPs
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2019.02.013

Although the silica-based nanoparticles (NPs) have been widely explored as the labels for sensing different targets, the simple and novel scheme, to impose a large number of signal molecules inside silica NPs, is challenge. Herein, a new scheme for this purpose was developed. This new strategy was based on densely doped polyethyleneimine (PEI) inside silica nanoparticles and forming the PEI@silica nanoparticles. Then, the Cu2+ was selected as the electrochemical signal molecule model to be loaded in PEI@silica nanoparticles the based on the strong coordination reaction of Cu2+ with PEI and test its signal amplification ability. Our results showed that 7.6 × 105 Cu2+signal ions could be loaded in a single PEI@silica nanoparticles. Thereafter, based on the discriminating interaction of this PEI/Cu2+/SiO2 NPs towards both ssDNA probes and ssDNA probe/mi-RNA complex, as well as the specific adsorption effect of this NPs on chemically modified electrode, a highly sensitive electrochemical method for detecting mi-RNA was developed and successfully used to detect mi-RNA in the human serum samples. Schematic illustration of the synthetic process of PEI/Cu2+/SiO2 NPs. [Display omitted] •A novel PEI core@silica shell nanoparticle was prepared.•The PEI core @ silica shell Nanoparticles can load a large number of Cu2+.•The PEI/Cu2+/SiO2 nanoparticles can discriminate ssDNA probes and ssDNA probe/miRNA complex.•the Cu2+ ions inside PEI/Cu2+/SiO2 nanoparticles can be used as the electrochemical signal molecules to sensitively detect microRNA.