Medical Bionanotechnology, Faculty of Allied Health Sciences, Chettinad Hospital & Research Institute (CHRI), Chettinad Academy of Research and Education (CARE), Kelambakkam, Chennai, 603 103, India.
Department of Chemistry and Biochemistry, Georgia Southern University, Statesboro, GA, 30460, USA.
Appl Biochem Biotechnol. 2023 Nov;195(11):6979-6993. doi: 10.1007/s12010-023-04475-0. Epub 2023 Mar 28.
Photodynamic therapy (PDT) has recently become significant as a clinical modality for cancer therapy and multidrug-resistant (MDR) infections, replacing conventional chemotherapy and radiation therapy protocols. PDT involves the excitation of certain nontoxic molecules called photosensitizers (PS), applying a specific wavelength of light to generate reactive oxygen species (ROS) to treat cancer cells and other pathogens. Rhodamine 6G (R6G) is a well-known laser dye with poor aqueous solubility, and lower sensitivity poses an issue in using PS for PDT. Nanocarrier systems are needed to deliver R6G to cancer targets since PDT requires a higher accumulation of PS. It was found that R6G-conjugated gold nanoparticles (AuNP) have a higher ROS quantum yield of 0.92 compared to 0.3 in an aqueous R6G solution, increasing their potency as PS. Cytotoxicity assessment on A549 cells and antibacterial assay on MDR Pseudomonas aeruginosa collected from a sewage treatment plant are the evidence to support efficient PDT. In addition to their enhanced quantum yields, the decorated particles are effective in generating fluorescent signals that can be used for cellular imaging and real-time optical imaging, and the presence of AuNP is a valuable addition to CT imaging. Furthermore, the fabricated particle exhibits anti-Stokes properties, which makes it suitable for use as a background-free biological imaging agent. As a result, R6G-conjugated AuNP is an effective theranostic agent that prevents the progression of cancer and MDR bacteria, along with contrasting abilities in medical imaging with minimal toxicity observed in in vitro and in vivo assays using zebrafish embryos.
光动力疗法（PDT）最近已成为癌症治疗和多药耐药（MDR）感染的重要临床治疗手段，取代了传统的化疗和放疗方案。PDT 涉及激发某些称为光敏剂（PS）的无毒分子，应用特定波长的光产生活性氧（ROS）来治疗癌细胞和其他病原体。若丹明 6G（R6G）是一种众所周知的激光染料，水溶性差，而较低的灵敏度在使用 PS 进行 PDT 时存在问题。需要纳米载体系统将 R6G 递送到癌症靶标，因为 PDT 需要更高的 PS 积累。研究发现，与水溶液中的 R6G 相比，R6G 修饰的金纳米粒子（AuNP）具有更高的 ROS 量子产率 0.92，增加了其作为 PS 的效力。对从污水处理厂收集的 A549 细胞进行细胞毒性评估和对多药耐药铜绿假单胞菌进行抗菌试验是支持有效 PDT 的证据。除了增强的量子产率外，修饰后的颗粒还能有效产生荧光信号，可用于细胞成像和实时光学成像，AuNP 的存在是 CT 成像的宝贵补充。此外，所制备的颗粒具有反斯托克斯性质，使其适合用作无背景的生物成像剂。因此，R6G 修饰的 AuNP 是一种有效的治疗和诊断剂，可预防癌症和 MDR 细菌的进展，并具有在体外和体内斑马鱼胚胎实验中观察到的最小毒性的对比能力，用于医学成像。
