Numerical Simulation of Enhancement of Superficial Tumor Laser Hyperthermia with Silicon Nanoparticles

Biodegradable and low-toxic silicon nanoparticles (SiNPs) have potential in different biomedical applications. Previous experimental studies revealed the efficiency of some types of SiNPs in tumor hyperthermia. To analyse the feasibility of employing SiNPs produced by the laser ablation of silicon nanowire arrays in water and ethanol as agents for laser tumor hyperthermia, we numerically simulated effects of heating a millimeter-size nodal basal-cell carcinoma with embedded nanoparticles by continuous-wave laser radiation at 633 nm. Based on scanning electron microscopy data for the synthesized SiNPs size distributions, we used Mie theory to calculate their optical properties and carried out Monte Carlo simulations of light absorption inside the tumor, with and without the embedded nanoparticles, followed by an evaluation of local temperature increase based on the bioheat transfer equation. Given the same mass concentration, SiNPs obtained by the laser ablation of silicon nanowires in ethanol (eSiNPs) are characterized by smaller absorption and scattering coefficients compared to those synthesized in water (wSiNPs). In contrast, wSiNPs embedded in the tumor provide a lower overall temperature increase than eSiNPs due to the effect of shielding the laser irradiation by the highly absorbing wSiNPs-containing region at the top of the tumor. Effective tumor hyperthermia (temperature increase above 42 °C) can be performed with eSiNPs at nanoparticle mass concentrations of 3 mg/mL and higher, provided that the neighboring healthy tissues remain underheated at the applied irradiation power. The use of a laser beam with the diameter fitting the size of the tumor allows to obtain a higher temperature contrast between the tumor and surrounding normal tissues compared to the case when the beam diameter exceeds the tumor size at the comparable power.

1550nm Infrared Laser Heating NaYF4:Er3+ Nanoparticle In Isolated Pig Liver and Up-conversion Fluorescence Intensity Ratio Temperature Measurement

Hyperthermia is an important means of cancer treatment which is called “tumor green therapy”. The clinical heat therapy heating sources include ultrasound, microwave, alternating magnetic field, infrared laser. However, it is still difficult to accurately measure the temperature of tumor hyperthermia and the dose of hyperthermia. Here, NaYF4:Er3+ nanoparticles were injected into a small part of isolated pig liver, and heated it with 1550nm infrared laser. At the same time, the laser excited the NaYF4:Er3+ nanoparticles to generate up-conversion green fluorescence. The fluorescence intensity ratio was used to measure the temperature of the heating part in real time.

Influence of Magnetic Scaffold Loading Patterns on their Hyperthermic Potential against Bone Tumors

Magnetic scaffolds have been investigated as promising tools for the interstitial hyperthermia treatment of bone cancers, to control local recurrence by enhancing radio- and chemotherapy effectiveness. The potential of magnetic scaffolds motivates the development of production strategies enabling tunability of the resulting magnetic properties. Within this framework, deposition and drop-casting of magnetic nanoparticles on suitable scaffolds offer advantages such as ease of production and high loading, although these approaches are often associated with a non-uniform final spatial distribution of nanoparticles in the biomaterial. The implications and the influences of nanoparticle distribution on the final therapeutic application have not yet been investigated thoroughly. In this work, poly-caprolactone scaffolds are magnetized by loading them with synthetic magnetic nanoparticles through a drop-casting deposition and tuned to obtain different distributions of magnetic nanoparticles in the biomaterial. The physicochemical properties of the magnetic scaffolds are analyzed. The microstructure and the morphological alterations due to the reworked drop-casting process are evaluated and correlated to static magnetic measurements. THz tomography is used as an investigation technique to derive the spatial distribution of nanoparticles. Finally, in silico multiphysics experiments are used to investigate the influence on the loading patterns on the interstitial bone tumor hyperthermia treatment.

Influence of Magnetic Scaffold Loading Patterns on their Hyperthermic Potential against Bone Tumors

Magnetic scaffolds have been investigated as promising tools for the interstitial hyperthermia treatment of bone cancers, to control local recurrence by enhancing radio- and chemotherapy effectiveness. The potential of magnetic scaffolds motivates the development of production strategies enabling tunability of the resulting magnetic properties. Within this framework, deposition and drop-casting of magnetic nanoparticles on suitable scaffolds offer advantages such as ease of production and high loading, although these approaches are often associated with a non-uniform final spatial distribution of nanoparticles in the biomaterial. The implications and the influences of nanoparticle distribution on the final therapeutic application have not yet been investigated thoroughly. In this work, poly-caprolactone scaffolds are magnetized by loading them with synthetic magnetic nanoparticles through a drop-casting deposition and tuned to obtain different distributions of magnetic nanoparticles in the biomaterial. The physicochemical properties of the magnetic scaffolds are analyzed. The microstructure and the morphological alterations due to the reworked drop-casting process are evaluated and correlated to static magnetic measurements. THz tomography is used as an investigation technique to derive the spatial distribution of nanoparticles. Finally, in silico multiphysics experiments are used to investigate the influence on the loading patterns on the interstitial bone tumor hyperthermia treatment.

Hyperthermia-mediated changes in the tumor immune microenvironment using iron oxide nanoparticles

Iron oxide nanoparticles (IONPs) have often been investigated for tumor hyperthermia. IONPs act as heating foci in the presence of an alternating magnetic field (AMF). It has been shown that...

Study on array antennas combined with nanoparticles for enhanced microwave hyperthermia of breast cancer

Tumor hyperthermia is to heat tumor tissue with biological thermal effect that can kill cancer cells when achieved effective treatment temperature. However, the temperature distribution of hyperthermia is uneven and it can not be accurately oriented to the tumor region. In this paper, an array antenna which can realize large-scale heating was designed for tumor microwave hyperthermia. ZrMOF-Cys nanoparticles (ZMC NPs) were prepared as the sensitizer of microwave hyperthermia. In the experiment of hyperthermia, array antenna and ZMC NPs are combined to achieve the goal of conformal hyperthermia and enhance the effect of hyperthermia. ZMC NPs have excellent heating effect, biodegradability and low cytotoxicity. ZMC NPs were injected into tumorbearing BALB/c mice by tail vein. Due to enhanced permeability and retention effect (EPR), ZMC NPs can enrich tumor sites to the greatest extent at 6 h. After 6 h of injection, the mice were treated with array antenna. The experimental results indicate that the combination of array antenna and ZMC NPs makes the temperature of tumor site higher than that of surrounding normal tissue, which has an excellent therapeutic effect, and the tumor inhibition rate reaches 87.52%. Phantom models experiments are also proved that the combination of array antenna and ZMC NPs can achieve the effect of conformal thermotherapy. This work provides a new direction for the development of conformal hyperthermia.

Preparation and Characterization of Active Targeting Dual-Functionalized Liposome with Anti-Tumor Ability and Optimized Fluorescent Intensity

Although the preparation of Indocyanine Green (ICG) liposomes obtained stronger performance than free ICG. With increase in depth of tissue, ICG exhibits limited background (SBR) and blurs structure characteristics. In this research, a Stearylamine-Bearing cationic liposome was prepared for improved fluorescence performance (higher SBR and deeper imaging depth). In addition, the effect of ICG and lipid interactions was explored. Hyaluronic acid is subsequently modified on the liposomes for prolonging blood circulation time and active tumor targeting. In vitro study confirmed that the liposome (HA-ICG-SA-LP) was capable of reversing surface zeta potential under acidic conditions in the presence of HAase which might enhance cellular uptake. Additionally, the photothermal heating of liposomes was investigated. The MTT assay showed that the liposome has strong cancer cell inhibition ability. In summary, HA-ICG-SA-LP exhibited a great potential for high sensitivity imaging and tumor hyperthermia.