PEGylated gold nanoprisms for photothermal therapy at low laser power density

Abstract

This paper developed small-sized PEGylated gold nanoprisms (GNPs) to induce photothermal therapy at low laser power density. Upon irradiation of laser at low power density (2 W cm -2 ), these PEGylated GNPs showed ultrahigh photothermal conversion efficacy (η ≈ 70%) and produced enough heat to kill human breast cancer cells. Figure 3. Representative DLS distribution of PEGylated (a) and CTAC-capped GNPs (b) in water. The dash lines represent the normalized DLS distribution. The spikes represent the raw intensity of DLS distribution. DLS distribution of PEGylated (c) and CTACcapped GNPs (d) reported as the correlation function.Since the localized surface plasmon resonance is highly sensitive to the shape of nanoparticles, the extinction spectrum of GNPs has been simulated by using the finitedifference time-domain (FDTD) method. As shown in Figure 4, when the edge length and thickness of GNPs were set as 55 and 20 nm, the simulation data was consistent with the experimental result in which the extinction peaked at 679 nm. Figure 4. (a) Perspective view of established GNPs model. (b) The scattering, absorption and extinction spectra of GNPs simulated by FDTD solutions. photothermal properties of PEGylated GNPsThe photothermal conversion efficacy of PEGylated GNPs was investigated as a function of concentration under NIR laser at 2 W cm -2 . Upon irradiation for 10 min, we observed that the maximum equilibrium temperature of the solution gradually increased with the concentration. The solution at 40 µg/mL showed a 39.3 ∘ C increase in temperature after irradiation, while no significant change was observed in ultrapure water (Figure 5a).These results demonstrated that PEGylated GNPs generated heat upon NIR laser irradiation with excellent photothermal conversion efficacy. Furthermore, PEGylated GNPs exhibited remarkable photothermal stability under NIR laser irradiation for five cycles (Figure 5b).

Applications of Gold Nanoparticles in Cancer Imaging and Treatment

“…The gold bellflowers showed photothermal conversion efficiency at 74%, which is higher than most reported gold nanoparticles. Ma and coworkers working with our group [40] demonstrated similar photothermal conversion efficiency (~70%) in triangular gold nanoprisms (Figure 3).…”

T 1-Weighted MR/CT dual-modality imaging-guided photothermal therapy using gadolinium-functionalized triangular gold nanoprism

“…This phenomenon has also been reported for other anisotropic particles. 26,30 The zeta potential of bare TGP was 5.59 AE 0.32 mV ( Fig. 1d).…”

“…21,22 Owing to their strong absorption in the near infrared (NIR) region and outstanding photothermal conversion capacity, gold nanostructures are suitable candidates for PTT. [23][24][25][26] In addition, as a high-Z element, gold has a large X-ray attenuation coefficient, which enables it to perform CT enhancement. 14,15 Moreover, by simple chemical modication gold nanostructures can be decorated with various functional groups, such as gadolinium compounds, to achieve MR imaging.…”

High and low molecular weight hyaluronic acid-coated gold nanobipyramids for photothermal therapy

“…The haemolysis assay was performed following the described protocol in our previous report, and the results were repeated 3 times. 42 This journal is © The…”