Laser Synthesized Core-Satellite Fe-Au Nanoparticles for Multimodal In Vivo Imaging and In Vitro Photothermal Therapy

Abstract

Hybrid multimodal nanoparticles, applicable simultaneously to the noninvasive imaging and therapeutic treatment, are highly demanded for clinical use. Here, Fe-Au core-satellite nanoparticles prepared by the method of pulsed laser ablation in liquids were evaluated as dual magnetic resonance imaging (MRI) and computed tomography (CT) contrast agents and as sensitizers for laser-induced hyperthermia of cancer cells. The biocompatibility of Fe-Au nanoparticles was improved by coating with polyacrylic acid, which provided excellent colloidal stability of nanoparticles with highly negative ζ-potential in water (−38 ± 7 mV) and retained hydrodynamic size (88 ± 20 nm) in a physiological environment. The ferromagnetic iron cores offered great contrast in MRI images with r2 = 11.8 ± 0.8 mM−1 s−1 (at 1 T), while Au satellites showed X-ray attenuation in CT. The intravenous injection of nanoparticles enabled clear tumor border visualization in mice. Plasmonic peak in the Fe-Au hybrids had a tail in the near-infrared region (NIR), allowing them to cause hyperthermia under 808 nm laser exposure. Under NIR irradiation Fe-Au particles provided 24.1 °C/W heating and an IC50 value below 32 µg/mL for three different cancer cell lines. Taken together, these results show that laser synthesized Fe-Au core-satellite nanoparticles are excellent theranostic agents with multimodal imaging and photothermal capabilities.

Multifunctional tunable ZnFe2O4@MnFe2O4 nanoparticles for dual-mode MRI and combined magnetic hyperthermia with radiotherapy treatment

“…23 The possibility of tuning the thermal properties of the nanoparticles by varying their structural and magnetic properties is an important aspect that determines the possibility of their use in hyperthermia and MRI. 39–41 To determine the effective anisotropy constant ( K eff ), the magnetization curves of the samples were measured at 90 K in accordance with Akulov's law. 42 Upon saturation, the field dependence of magnetization can be described using eqn (2):where M S is the saturation magnetization, a is the parameter responsible for the orientation of the anisotropy axes, and H is the external magnetic field.…”

Smart Chemical Oxidative Polymerization Strategy To Construct Au@PPy Core–Shell Nanoparticles for Cancer Diagnosis and Imaging-Guided Photothermal Therapy

“…The temperature was recorded every 30 s. Before and after the 5 cycles, the UV–vis–NIR spectra were recorded. The photothermal conversion efficiency was evaluated according to the previously reported methods. , Briefly, 1 mL, 300 mg/L Au@PPy dispersion in a quart cuvette was irradiated with an 808 nm NIR laser for 15 min and then cooled naturally for 15 min. The temperature was monitored by a thermocouple probe every 30 s. Then, the photothermal conversion efficiency was calculated by the next equation.…”

“…Among them, computed tomography (CT) is an imaging technique extensively used in the clinic due to its inherent merits like noninvasion, high resolution, deep tissue penetration capability, and low-cost effectiveness. , With the assistance of contrast agents, CT can make a clear distinction between soft tissue and provide complementary anatomical information for tumors. The materials with large atomic numbers (Ta, 73; Au, 79; Bi, 83) and X-ray attenuation coefficients (Ta, 4.30; Au, 5.16; Bi, 5.74 cm 2 g –1 at 100 keV) can be potentially applied as CT contrast agents. ,, Among the various metal elements, Au is an ideal candidate for constructing CT contrast agents with strong X-ray attenuation. − Furthermore, due to Au nanoparticles possessing negligible toxicity, prominent biocompatibility, easily controlled in morphology, and simple surface modification with a variety of polymers, the Au-based nanoparticles can be utilized for combined treatment, which significantly enhanced the therapeutic effect of tumors …”

A tissue-mimicking phantom with flexible optical properties for studying photoacoustic response of nanoparticles

“…Moreover, this nanomaterial is very biocompatible, especially when its colloidal solutions are synthesized without using of potentially toxic chemical compounds. In particular, we recently introduced new laser-synthesized colloidal solutions of bare TiN NPs and a variety of other NPs [22][23][24][25] . and demonstrated their good biocompatibility both in vivo and in vitro as well as high photothermal effect in vitro even at very low concentrations 20,26,27 .…”