An electrochemiluminescence aptasensor for tumor cells assay based on signal amplification of Ru(II) covalently doped silica nanoparticles

A sensitive and stable aptasensor for the assay of tumor cells based on signal amplification with novel ruthenium(II) covalently doped silica nanoparticles (Si NPs) was presented for the first time. For the proposed aptasensor, one target signal could be transformed into multiple ECL signals of Ru(II) markers since a single Si NP could be loaded with multiple of Ru(II) markers. The binding of Si NPs on the electrode further increased the sensor sensitivity. The advantage of extraordinary stability of covalently doped Si NPs made the sensor exhibit excellent reproducibility. The new method for the assay of tumor cells is reliable. (C) 2011 Elsevier B.V. All rights reserved.