Abstract
The drug delivery application of carbon-based quantum dots is a new platform in the medical field. We report a unique morphological structure called carbon-dots clathrates (C-dots(cL)) conjugated with folic acid (FA) for targeted delivery of methotrexate (MTX), an anti-cancer drug under physiological conditions followed by photothermal (PIT) and photodynamic (PDT) treatment on cancer cells. Under physiological milieu, the C-dots(cL)-MTX-FA complex are pH-dependent and it can control release the anti-cancer drug in vitro. Furthermore, in vivo studies were also performed by using genetically-induced pancreatic cancer model to comprehend the in vivo pharmacokinetics and tissue distribution pattern of C-dots(cL)-MTX-FA complex. The results demonstrated that the CQD was able to deliver high concentration of MTX in tumour tissues in contrast to the non-tumour tissues. The impact of near-infrared (NIR) laser (1064 nm; Nd-YAG) on the CQDs system was found to be extremely effective for the rapid release of MD (in tumour tissues. The generation of reactive oxygen species (ROS) by C-dots(cL) upon irradiation of NIR laser was evaluated using flow cytometry. After conjugation with the C-dots(cL), the half-life of the MTX drug (t(1/2)), elimination constant (K-e1), area under the curve (AUC) was drastically improved to prove the efficacy of C-dot(cL) as a powerful drug vehicle. This study has significantly improved the cancer theranostics research using C-dots(cL) to act as a multi-functional nanomaterial for imaging and as a drug delivery agent. (C) 2017 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.