Novel concept of the smart NIR-light–controlled drug release of black phosphorus nanostructure for cancer therapy

Introduction

This article explores an innovative cancer treatment method using a drug delivery system that employs near-infrared (NIR) light. This approach controls how drugs are released from a black phosphorus (BP) nanostructure, aiming to target tumor sites more precisely and to enhance treatment effectiveness while minimizing side effects.

Background

Cancer is a major global health challenge and traditional therapies like surgery, chemotherapy, and radiotherapy often fall short in effectiveness. Current methods of drug delivery face challenges like lack of precision and effectiveness. Therefore, new methods for drug delivery are necessary. Localized drug delivery strategies can improve treatment results and alleviate associated pain and complications.

Research Objective

The study's goal is to show how effective BP-based hydrogel systems can be when releasing drugs triggered by NIR light. It leverages BP's unique properties for controlled drug delivery and biodegradability in living systems. A biodegradable drug delivery system (DDS) is proposed that can adjust drug release rates based on various factors like light intensity, exposure duration, BP concentration, and hydrogel composition.

Experimental Design

Development of BP@Hydrogel

BP nanosheets (BPNSs) were created using a modified liquid exfoliation method and incorporated into a hydrogel made from agarose, a safe, FDA-approved material. The hydrogel's thermodynamic properties were tested to develop a suitable drug delivery protocol under different NIR light intensities.

Characterization of BPNSs and Hydrogel

To understand the materials better, transmission electron microscopy (TEM) and atomic force microscopy (AFM) were used for characterization. The BP showed strong absorption of NIR light and high photothermal conversion efficiency of 38.8%. When exposed to NIR, the system was able to release doxorubicin (DOX) in a controlled way, influenced by several parameters.

Results

Drug Release Mechanism

When NIR light was applied, it increased the hydrogel's temperature, causing it to soften and melt. This process facilitated the drug's diffusion and release. The study found that the drug release could be effectively regulated by adjusting the light's power and duration, demonstrating a sophisticated nano-platform for cancer therapy.

In Vitro and In Vivo Experiments

In vitro tests: Various types of human cancer cells (like MDA-MB-231, A549, HeLa, and B16) were used to evaluate the BP@Hydrogel platform’s effectiveness. Results showed no harmful effects on human cells at high BP concentrations, confirming its safety.
In vivo studies: Tests in animal models indicated significant tumor reduction when using BP@Hydrogel with NIR light therapy, outperforming treatments with free DOX or hydrogel alone. The system exhibited low toxicity and showed no significant damage to normal tissues post-treatment, as per histological analysis.

Discussion

The BP@Hydrogel platform represents a substantial advancement in cancer drug delivery technology. Its high biocompatibility, biodegradability, and capability for precise, light-controlled drug release makes it a promising option. The study advocates for the potential of this technology to transform clinical practices in cancer treatment, offering a patient-tailored drug administration method.

Conclusion

The novel BP@Hydrogel system for NIR-light controlled drug release stands out as a promising option for effective cancer treatment because of its excellent biocompatibility, sustained drug release capability, and degradability. Future research will focus on improving synthesis methods and assessing safety and efficacy in broader clinical contexts.