Photo-decomposable Organic Nanoparticles for Combined Tumor Optical Imaging and Multiple Phototherapies

Abstract

Combination of photodynamic therapy (PDT) with photothermal therapy (PTT) has achieved significantly improved therapeutic efficacy compared to a single phototherapy modality. However, most nanomaterials used for combined PDT/PTT are made of non-biodegradable materials (e.g., gold nanorods, carbon nanotubes, and graphenes) and may remain intact in the body for long time, raising concerns over their potential long-term toxicity. Here we report a new combined PDT/PTT nanomedicine, designated SP3NPs, that exhibit photo-decomposable, photodynamic and photothermal properties. SP3NPs were prepared by self-assembly of PEGylated cypate, comprising FDA-approved PEG and an ICG derivative. We confirmed the ability of SP3NPs to generate both singlet oxygen for a photodynamic effect and heat for photothermal therapy in response to NIR laser irradiation in vitro. Also, the unique ability of SP3NPs to undergo irreversible decomposition upon NIR laser irradiation was demonstrated. Further our experimental results demonstrated that SP3NPs strongly accumulated in tumor tissue owing to their highly PEGylated surface and relatively small size (~60 nm), offering subsequent imaging-guided combined PDT/PTT treatment that resulted in tumor eradication and prolonged survival of mice. Taken together, our SP3NPs described here may represent a novel and facile approach for next-generation theranostics with great promise for translation into clinical practice in the future.

A Dual‐Model Imaging Theragnostic System Based on Mesoporous Silica Nanoparticles for Enhanced Cancer Phototherapy

“…Hyperthermia induced by PTT can increase cellular uptake of photosensitizer's and local oxygen's concentration, thus accelerating intracellular ROS production for enhanced PDT efficacy . Meanwhile, ROS produced by PDT can make tumor cells sensitive to the hyperthermia, which is favorable for PTT . Among various photosensitizers, indocyanine green (ICG), which can be activated by 808 nm near‐infrared (NIR) light, has shown extraordinary capacity to induce both hyperthermia and ROS for PTT/PDT combination therapy .…”

Prototypic Heptamethine Cyanine Incorporating Nanomaterials for Cancer Phototheragnostic

“…Cypate incorporating nanomaterials have also been used for cancer PTT/PDT ( Table 4 ) as well as for tumor visualization through NIR fluorescence imaging and PAI (Table ). For this purpose, Cypate (a carboxylated ICG derivative) has been mostly loaded into nanostructures or conjugated to polymers in order to attain materials capable of assembling into nanostructures …”

“…In this context, Miao et al prepared a PEG‐Cypate conjugate that was used in the assembly of micelles for application in cancer PTT/PDT and imaging . In vivo, the PEG‐Cypate micelles achieved a higher tumor uptake than free Cypate, enabling a superior tumor visualization through NIR fluorescence imaging.…”

Nano-Medicine for Thrombosis: A Precise Diagnosis and Treatment Strategy

“…Photo-therapy (photothermal therapy, PTT; photodynamic therapy, PDT) has also been developed as a noninvasive strategy for the treatment of multiple diseases [111][112][113][114]. Photo-therapy agents can convert laser radiation into a local temperature increase or reactive oxygen species (ROS), leading to hyperthermic injury of the treated cells [115].…”