A tumor microenvironment–induced absorption red-shifted polymer nanoparticle for simultaneously activated photoacoustic imaging and photothermal therapy

Abstract

Tumor microenvironment–responsive therapy has enormous application potential in the diagnosis and treatment of cancer. The glutathione (GSH) level has been shown to be significantly increased in tumor tissues. Thus, GSH can be used as an effective endogenous molecule for diagnosis and tumor microenvironment–activated therapy. In this study, we prepared a tumor microenvironment–induced, absorption spectrum red-shifted, iron-copper co-doped polyaniline nanoparticle (Fe-Cu@PANI). The Cu(II) in this nanoparticle can undergo a redox reaction with GSH in tumors. The redox reaction induces a red shift in the absorption spectrum of the Fe-Cu@PANI nanoparticles from the visible to the near-infrared region accompanying with the etching of this nanoparticle, which simultaneously activates tumor photoacoustic imaging and photothermal therapy, thereby improving the accuracy of in vivo tumor imaging and the efficiency of photothermal therapy. The nanoparticle prepared in this study has broad application prospects in the diagnosis and treatment of cancer.

A Unique Multifunctional Nanoenzyme Tailored for Triggering Tumor Microenvironment Activated NIR‐II Photoacoustic Imaging and Chemodynamic/Photothermal Combined Therapy

“…[22] For example, TME-related overexpressed GSH can simultaneously activate the PAI and photothermal therapy (PTT) functions of specifically designed nanoparticles. [23] TME-activated nanoprobes also present the advantages of accuracy, high efficiency, low interference of background signal, and only slight damage to normal tissue. So far, few studies have reported on TME-activated nanoprobes exploiting the NIR-II biological window.…”

Targeted contrast agents and activatable probes for photoacoustic imaging of cancer

“…275–277 Therefore, developing GSH probes is of interest in understanding its role in cancer development and to facilitate the application of GSH-targeted cancer therapy. Due to the deep tissue penetration of PA imaging, many activatable PA probes have been developed as tools to study the in vivo behavior of GSH, 278–289 and here we introduce some recent progress in this area.…”

“…23c). 290 Utilizing the reductive nature of GSH, the Cu 2+ in the Fe-Cu@PANI probe can undergo a redox reaction to yield NPs with a size reduction and a red-shift of the absorbance maximum. To evaluate the PA imaging performance of Fe-Cu@PANI, the probe was injected into both the normal muscle tissue (bearing no tumor) and the xenograft 4T1 tumor side of the mice.…”

Conjugated Polymers: Optical Toolbox for Bioimaging and Cancer Therapy

“…As a result, the penetration depth and imaging resolution were greatly enhanced compared with optical imaging techniques. [106][107][108] In this process, PA agents, including organic dyes, [109][110][111] metallic nanoparticles, [112][113][114] carbon nanotubes, [115,116] and 2D materials, [117][118][119] have been widely explored in the past decade. However, most of them suffered severely because of their intrinsic imperfections in poor photostability and low biocompatibility.…”