Gold nanostar-enhanced chemiluminescence probe for highly sensitive detection of Cu(II) ions

Abstract

Gold nanostars have interesting and unique surface plasmonic properties originating from their multi-branched shape with sharp tips. We demonstrate here the first use of gold nanostars in chemiluminescence (CL) field by studying their effect on H2O2-IO4− reaction. Nanostars, prepared by seed-mediated growth in poly(vinylpyrrolidone) solution in DMF, remarkably enhance the CL intensity of this reaction. On the basis of some evidence- we show that the enhancing effect of gold nanostars is most probably due to the coupling of CL emission to surface plasmons of nanostar tips. We applied the gold nanostar-based CL system as an ultrasensitive and selective probe for detection of nM levels of Cu(II) ions. The probe has a linear calibration range from 2.0nM to 9.0μM with a detection limit of 0.9nM. The developed CL method was validated by analysis of a certified reference material and applied for real environmental and biological samples.