Plasmonic Nanocomposite Implants for Interstitial Thermotherapy: Experimental and Computational Analysis

Abstract

The ferromagnetic implant (thermoseeds) technique offers desirable features for interstitial thermotherapy. However, its efficacy has been reported to be limited by issues that are related to the properties of the metal alloys that are used to fabricate them and the high number of thermoseeds needed to achieve therapeutic temperature levels. Here, we present the results of a combination of experimental and computational analysis of plasmonic nanocomposite implants (photoseeds)—a combination of Au nanoparticles (NPs) and poly-dimethylsiloxane (PDMS)—as a model material. We performed structural and optical characterization of the Au NPs and repared Au-PDMS nanocomposites, followed by an elucidation of the heat generation capabilities of the Au-PDMS photoseeds in aqueous solution and in-vitro cancer cell suspension. Based on the experimental results, we developed a three-dimensional (3D) finite element method (FEM) model to predict in-vivo thermal damage profiles in breast tissue. The optical absorbance of the Au-PDMS photoseeds were increasing with the concentration of Au NPs. The photothermal measurements and the in-vivo predictions showed that the photothermal properties of the photoseeds, characteristics of the laser sources, and the duration of heating can be tuned to achieve therapeutic temperature levels under in-vitro and in-vivo conditions. Collectively, the results demonstrate the feasibility of using photoseeds for interstitial thermotherapy.

Laser‐induced heating of polydimethylsiloxane‐magnetite nanocomposites for hyperthermic inhibition of triple‐negative breast cancer cell proliferation

“…The type of laser applied in many photothermal investigations was near infrared, with wavelength spectra of 785 nm up to 1046 nm, with 808 nm wavelength used more frequently, according to a review by Fekrazad et al 76 Hence, the 808 nm wavelength was the most effective in prior studies [77][78][79] of the photothermal destruction of cancer cells. 76 In addition, the current results suggest that the magnetitereinforced PDMS nanocomposites reinforced with 5% weight percentage of MNPs exhibit the best heating characteristics for controlled laser-induced hyperthermia at depths up to 8 mm below the surface, when the power of the incident laser is 0.6 W. However, for laser power above 0.6 W, the current work also suggests that the higher temperatures that result from laser illumination at higher incident powers (above 0.6 W).…”

“…The type of laser applied in many photothermal investigations was near infrared, with wavelength spectra of 785 nm up to 1046 nm, with 808 nm wavelength used more frequently, according to a review by Fekrazad et al 76 Hence, the 808 nm wavelength was the most effective in prior studies 77–79 of the photothermal destruction of cancer cells 76 …”

Mechanical and thermal properties of polydimethylsiloxane/magnetite nanocomposites for cancer treatment by localized hyperthermia and photothermal ablation

“…31 It has also been reported that iron oxide nanoparticles are more widely used than other magnetic nanoparticles due to their biocompatibility and chemical inertness that make them suitable for medical, pharmaceutical and therapeutic applications. 16,32,33 Also magnetite/PDMS nanocomposites are biocompatible, inert and nontoxic, 34 making them excellent candidates for applications in biomedical devices for breast cancer treatment.…”