Poly-amidoamine Dendrimers@Fe3O4based Electrochemiluminescent Nanomaterials for Biosensing of Liver Cancer Biomarkers

Electrochemiluminescence (ECL) of poly-amidoamine (PAMAM) dendrimers functionalized to Fe(3)O(4)nanoparticles (PAMAM@Fe(3)O(4)NPs) based on Ru(bpy)(3)(2+)complex is reported. Different generations of PAMAM dendrimer consisted of 5 (D5), 10 (D10), 8 (D8) and 16 (D16) surface primary amine-terminated groups. D5@Fe(3)O(4)NPs enhanced ECL emission in comparison to others. A possible mechanism is elucidated based on structural functionality of PAMAM with respect to amines, carbonyl, hydroxyl groups and size-based diffusion. ECL biosensing of alpha-fetoprotein (AFP) and glypican-3 (GPC-3) using 1 mM tri-propylamine is demonstrated using D5@Fe3O4NP@antibodies as detection probes. Detection limit for AFP and GPC-3 was 6 pg/mL and 0.03 pg/mL, respectively.