Easy and high-throughput model provided for evaluating efficiency of photodynamic agent

Recently, the team led by Prof. HUANG Qing at the Institute of Intelligent Machines, Hefei Institutes of Physical Science (HFIPS) provided a new photodynamic agent and introduces C. elegans as an easy and high throughput model to evaluate the Photodynamic Agent (PDT) efficiency.

Conventional photosensitizers have the drawbacks such as the low singlet oxygen (¹O₂) quantum yield and the problem of photobleaching, which limit the clinical application of Photodynamic therapy (PDT).

In this research, carbon quantum dots (CQDs) derived from broccoli as a natural biomass carbon source were fabricated as a photodynamic agent via a simple hydrothermal method, which showed outstanding Photodynamic ability testified in the Caenorhabditis elegans (C. elegans) models. The as-prepared broccoli-derived CQDs (BCQDs) exhibited high photostability, excellent water solubility, and could generate (¹O₂) effectively under irradiated light with a wavelength 660 nm.

The results revealed the PDT efficiency of BCQDs by causing DNA damage of the worms which eventually induced germline apoptosis, as confirmed by measuring the egl-1 fold induction in the loss function mutants hus-1(op244) and cep-1(w40). In addition, the lack of germline apoptosis in the mutants with the loss of function of the genes for germline apoptosis due to DNA damage like hus-1(op244), cep-1(w40), and egl-1(n487), revealed that PDT efficiency of BCQDs was dependent on the induction of germline apoptosis mediated by the cep-1/p53 pathway upon DNA damage.

This work has not only provided the effective material for the potential PDT application but also introduced a rapid and high-throughput screening model for future PDT research.

The results have been published in Biomaterials Science.