Dual-Stimuli-Responsive, Polymer-Microsphere-Encapsulated CuS Nanoparticles for Magnetic Resonance Imaging Guided Synergistic Chemo-Photothermal Therapy

Abstract

Integrating biomedical imaging and multimodal therapies into one platform for enhanced anticancer efficacy is of great significance. Herein, a core/shell structured nanotheranostic (CuS@copolymer) for magnetic resonance imaging (MRI)-guided chemo-photothermal therapy was simply prepared via emulsifier-free emulsion polymerization with the full participation of hydrophilic CuS NPs, styrene (St), N-isopropylacrylamide (NIPAm), methacrylic acid (MAA), and polymerizable rare earth complex (Gd­(AA)3phen). The synthesized multifunctional microspheres with excellent biocompatibility exhibited high loading capacity (15.3 wt %) for DOX·HCl and excellent drug release under low pH and high temperature. The photosensitive CuS cores which can simultaneously efficiently absorb near-infrared (NIR) light and convert NIR light to fatal heat, leading to a synergistic therapeutic effect combined photothermal therapy (PTT) with chemotherapy. Moreover, the temperature sensitive copolymer attached onto the CuS nanoparticles was able to be productively infected by the thermal effect and give rise to a highly controllable DOX release. Furthermore, the CuS@copolymer/DOX showed an enhanced therapeutic efficacy against 4T1 cells than separate photothermal therapy or chemotherapy. Additionally, the drug delivery procedure could be visualized by in vivo MR images and the longitudinal relaxivity (r 1) was calculated to be 10.72 mM–1 s–1. These results suggest the CuS@copolymer microspheres highly attractive candidates for biomedical applications.

Polymer‐Brush‐Grafted Mesoporous Silica Nanoparticles for Triggered Drug Delivery

“…In order to overcome this problem, DDSs capable of responding to near‐infrared radiation (NIR) with higher penetration capacity, have been recently reported. Among them, the combination of photosensitizing agents with temperature responsive polymer “gate‐keeper” draw much attention since the photosensitizing agents can effectively absorb NIR light energy sources and convert luminous energy into local heat, then the temperature sensitive polymer would be continuously affected by the thermal effect, giving rise to a highly controllable DOX release . For example, Yang et al .…”

“…To address these problems, stimuli‐responsive NPs with “smart” gatekeepers, which can respond to local cell microenvironment such as pH, temperature, enzyme, redox and external triggers like light and ultrasound, are regarded as ideal tools to deliver drugs ,. Considerable studies associated with polymer‐based micelles or microspheres, liposomes, silica, titanium dioxide and carbon NPs as stimuli‐responsive drug carriers have been exploited.…”

“…To address these problems, stimuli‐responsive NPs with “smart” gatekeepers, which can respond to local cell microenvironment such as pH, temperature, enzyme, redox and external triggers like light and ultrasound, are regarded as ideal tools to deliver drugs ,. Considerable studies associated with polymer‐based micelles or microspheres, liposomes, silica, titanium dioxide and carbon NPs as stimuli‐responsive drug carriers have been exploited. Among these carriers, MSNs have gained tremendous interest attributed to their remarkable features: (1) MSNs have unique pore characteristics to encapsulate various drugs, overcoming the poor water solubility and stability of drugs and also enhancing their bioavailability; (2) MSNs are biocompatible and can be safely taken up by living cells through endocytosis; (3) their surface active silanol groups make these NPs readily modifiable with different molecules to achieve various functions, e. g., responsive to different stimuli.…”

Recent Advances in Functional Polymer Decorated Two‐Dimensional Transition‐Metal Dichalcogenides Nanomaterials for Chemo‐Photothermal Therapy

“…Recently, more attention has been paid to synergistic therapy by simultaneously combining different modalities of treatment into a single platform . Taking advantages of ultrathin 2D structure and strong optical absorption in the NIR range, 2D TMDCs exhibit great potential as a novel nanoplatform for both photo‐responsive drug delivery and therapy . The combination of PTT and chemotherapy has many advantages.…”

“…[68] Ta king advantages of ultrathin 2D structure and strong opticala bsorption in the NIR range, 2D TMDCs exhibit great potential as an ovel nanoplatform for both photo-responsived rug delivery and therapy. [69] The combination of PTT and chemotherapy has many advantages. Under laser irradiation, PTT agents can transform the light energy into local high temperature and directly ablate tumor cells.…”