Simple Model for Gold Nano Particles Concentration Dependence of Resonance Energy Transfer Intensity

Abstract

Gold nano particles (GNPs) concentration dependence of the energy transfer occurs between the fluorophores and GNPs is investigated. In the case of theses pairs, GNPs can enhance or quench the fluorescence of fluorophores depending upon the relative magnitudes of two energy transfer mechanisms: i) the plasmonic field enhancement at the fluorophores emission frequencies (plasmon coupled fluorescence enhancement) and ii) the localized plasmon coupled Forster energy transfer from fluorescent particles to gold particles, which quenches the fluorescence. The competition of these mechanisms is depending on the spectral overlap of fluorophores and GNPs, their relative concentration, excitation wavelength. Simple two branches surface plasmon polariton model for GNPs concentration dependence of the energy transfer is proposed. The experimental data and theoretical results confirm our findings.

Molecular beacon anchored onto a graphene oxide substrate

“…The decay rate for linker length higher than 10 nm is almost comparable to the decay rate of the QD without any GO which agrees with the fact that within 10 nm the QD is almost 85% quenched [29]. The expression for the decay rate is given as where QD G =decay rate of the QD emission without GO, ϑ=orientation factor based on parallel and perpendicular orientation of dipoles, 0 l =free-space emission wavelength [27] and appears to be similar to the FRET theory:…”

“…The energy transfers between semiconductor QD and quenchers are mediated by two main methods based on the size of the latter. For a quencher with a radius smaller than 1.5 nm, the donor-acceptor (D-A) pair behaves as FRET (d -6 dependency) and if its higher nanometal surface energy transfer (NSET)-d -4 dependency-prevails because with higher radius the surface area increases [26,27]. Hence, the energy transfer efficiency for CdTe/ZnS core-shell QD and AuNP (1.4 nm) is given as FRET:…”

Role of gold nanoparticles in advanced biomedical applications

“…12). [252][253][254] In a study, single stranded DNA was conjugated to GNPs for the determination of the complementary DNA strand. 255 Upon hybridization between DNA strands, the red color solution of GNPs was changed to violet/blue.…”