Influence on fluorescence properties of hyperbranched poly(amidoamine)s by nano golds

Abstract

The influence of gold nanoparticles (GNPs) and gold nanodots (GNDs) on fluorescence properties of hyperbranched poly(amidoamine)s (HPAMAMs) which were synthesized by Michael addition of 1-(2-aminoethyl) piperazine (AEPZ) and methyl acrylate (MA) was investigated in this study. It was found that GNPs with definite surface plasma absorption can quench the fluorescence of HPAMAMs. With the increasing of the concentration of GNPs, the fluorescence intensity of HPA-MAMs decreased correspondingly, and varied linearly at low concentration of GNPs. This phenomenon was owing to the fluorescence resonance energy transfer (FRET) between the HPAMAMs and GNPs. In contrast, the complex with smaller GNDs encapsulated in the interior of the HPAMAMs presented greatly enhanced emission. Those results show that the size of nano golds may be used to adjust the fluorescence properties of HPAMAMs and may extend potential applications of HPA-MAMs and GNPs.

Facile one-pot synthesis of fluorescent hyperbranched polymers for optical detection of glucose

“…[3][4][5][6][7][8] For example, we have reported the hyperbranched poly (amidoamine)s (HPAMAMs) that synthesized by Michael addition of 1-(2-aminoethyl) piperazine (AEPZ) and methyl acrylate (MA) can emit bright blue fluorescence intensity under excitation wavelength. [9,10] The fluorescence intensity of the polymers increased correspondingly with the increasing tertiary nitrogen in the molecular structure by alkylation of the residual amino protons of HPAMAMs with propylene oxide. [11] In particular, there has been increased research interest in the development of glucose-sensitive polymeric systems that exhibit different fluorescent level in response to changing glucose concentration, so as to mimic the natural response of the body.…”

Imaging and Therapeutic Applications of Optical and Thermal Response of SPION-Based Third Generation Plasmonic Nanodendrimers

“…The shift of fluorescence spectra could be explained by strong interaction between gold crystals and amine groups of dendrimer [35]. Optical properties of Au-NPs are highly sensitive to their particle size and have an effective influence on the fluorescence spectra of dendrimer [39] [40]. This is because of the internal interaction between flexible structure of dendrimer and rigid structure of entrapped Au-NPs, whereas the larger particles damp the fluorescence of dendrimers.…”

“…Other researches indicate that peaks at 280 and 320 nm represent the aggregation of Au-NPs [10] [37] [38]. It should be mentioned that location and shape of surface plasmon resonance is strongly dependent on the particle size of material [39] [40] and the particle aggregation results in reduction of gold plasmon band intensity [38]. As it is seen in Figure 3, the peak ratio of 520 nm to 280 nm increases over the time which indicates the formation of Au-NPs.…”

Multifunctional Nanoplatform for Targeted Laser-induced Hyperthermia and Microscopy of Breast Cancer Cells using SPION-based Gold and Folic Acid Conjugated Nanodendrimers: An in vitro Assay

“…AuNPs have an effective influence on the fluorescence spectra of dendrimer [45,67] due to the internal interaction between flexible structure of dendrimer and rigid structure of entrapped AuNPs, whereas the larger particles damp the fluorescence of dendrimers. These phenomena could be explained in terms of fluorescence resonance energy transfer (FRET) [67].…”

“…Figure 2A shows the TEM images of nanocomposites synthesized by three different reducing agents where those prepared by NaBH 4 (Figure 2a) are larger compared to those obtained by hydrazine sulfate (Figure 2b) and pre-synthesized AuNPs (Figure 2c). This is thought to be due to interaction of such nanoparticles with surface amine group of dendrimers hence forming a larger particles in the expense of smaller particles [44,45]. When hydrazine sulfate was used as a reducing agent, smaller particles with a homogeneous distribution was obtained which could be readily entrapped within the MDs cavity [46].…”