Prussian blue nanoparticles for laser-induced photothermal therapy of tumors

Abstract

We describe Prussian blue nanoparticles (PB NPs) for laser-induced photothermal therapy (PTT) of tumors. The PB NPs exhibit strong absorbance at near infrared (NIR) wavelengths, are stable, non-toxic, and have 20.5% photothermal conversion efficiencies. PTT with PB NPs in a mouse model of neuroblastoma resulted in marked tumor debulking, increased tumor-free days, and decreased tumor growth rates in tumor-bearing mice. These findings demonstrate the clinical potential of PB NPs for PTT of tumors.

Composite iron oxide–Prussian blue nanoparticles for magnetically guided T₁-weighted magnetic resonance imaging and photothermal therapy of tumors

“…Additionally, the nanoparticles retained their photothermal heating properties over four cycles of heating and cooling ( Figure 4C) indicating their stability as photothermal agents over multiple heating cycles. Finally, studies conducted to calculate the photothermal conversion efficiency ( Figure 4D) demonstrated that the nanoparticles had a photothermal conversion efficiency of 16.1%, which is consistent with the previously determined photothermal conversion efficiency of Prussian blue nanoparticles (around 20%) 35 despite others). 32,38,39 Similarly, T2W scans demonstrated that the Fe 3 O 4 @GdPB nanoparticles generated increased contrast in a concentration-dependent manner ( Figure 3B), ie, increased darkening with increasing concentrations, similar to Fe 3 O 4 nanoparticles, which have been well-described in the literature.…”

“…35 The PTT capabilities of the Where h is the heat transfer coefficient, A is the surface area of heat transfer of the system, T max is the maximum system temperature, T amb is the ambient temperature, Q 0 is the rate of heat input due to absorption of light energy by water, I is the incident laser power, and A λ is the absorbance of the Fe 3 O 4 @GdPB at 808 nm.…”

“…Our observations of significantly elevated temperatures over basal temperatures even in the Fe 3 O 4 @GdPB-treated group are not unexpected given that our previous studies in the same Neuro2a model have demonstrated that NIR irradiation of tumors even in the absence of PTT agents can elevate tumor surface temperatures by 5°C-10°C. 35 Additionally, when using nanoparticlebased PTT agents particularly at short time intervals after tail-vein injection (ie, ,1 h), further heating is caused by nanoparticles circulating through tumor vasculature that are irradiated by the laser (intravascular heating). The addition of magnet concentrates a larger amount of nanoparticles within the tumors, which accounts for the heating observed in the Fe 3 O 4 @GdPB + magnet-treated group above the Fe 3 O 4 @ GdPB-treated.…”

“…Tumor growth was monitored by routine caliper measurements, as previously described. 35,37 All treatments commenced only after the Neuro2a tumors reached a diameter of at least 5 mm (~60 mm 3 ). Tumor-bearing mice were divided into three groups (n$9 mice/group): 1) untreated group: receiving no further treatment, 2) Fe 3 O 4 @ GdPB group: receiving 100 µL of 1 mg/mL Fe 3 O 4 @GdPB by tail vein injection, and 3) Fe 3 O 4 @GdPB + magnet group: receiving 100 µL of 1 mg/mL Fe 3 O 4 @GdPB by tail vein injection followed by application of an external magnetic field for 10 minutes; by externally affixing a 3,000 Gauss magnet (0.25″×0.25″×0.25″ Nickel-plated neodymium; K&J Magnetics Inc, Pipersville, PA, USA) to the surface of the tumors for mice in this group.…”

Prussian blue/serum albumin/indocyanine green as a multifunctional nanotheranostic agent for bimodal imaging guided laser mediated combinatorial phototherapy

“…PB and its analogues possess magnetic properties, so PB nanoparticles can act as an MRI contrast agent [16]. In addition, recently PB nanoparticles have also emerged as a new generation of photothermal agent owing to its high absorption in the NIR spectrum [17,18]. Since then, several theranostic nanoparticles have been developed using PB nanoparticles.…”