New generation of β-cyclodextrin-chitosan nanoparticles encapsulated quantum dots loaded with anticancer drug for tumor-target drug delivery and imaging of cancer cells

The objective of this study was to report the drug delivery system that can integrate the functional building blocks for optical pH-sensing, cancer cell imaging and controlled drug release into a single nanoparticle. The CD/SAHA-QDs-CS/FA nanoparticles were prepared by in-situ immobilization of ZnSe/ZnS quantum dots (QDs) in β-cyclodextrin (CD) and chitosan (CS) polymer loaded with suberoylanilide hydroxamic acid (SAHA). Synthetic CD/SAHA-QDs-CS/FA nanoparticles were approximately 100 nm in size and with blue fluorescence. The drug encapsulation efficiency of nanoparticles was 22.36 % and the encapsulated drug was released via a controlled release mechanism after a 9 h plateau was reached. The efficiency of the drug release in tumor microenvironments (pH 5.3 buffer solutions) was higher than that in physiological pH 7.4. In vitro cytotoxicity assay results showed that the blank nanoparticles had no cytotoxicity and therefore can be used as the fluorescence tracer, and the SAHA-encapsulated nanoparticles expressed an anticancer effect. Confocal microscopy and in vivo imaging studies showed that the developed nanoparticles had cytotoxicity in resistant cancer cells and preferentially accumulated in tumors. CD/SAHA-QDs-CS/FA nanoparticles with excellent long-term optical properties have great prospects for the development of targeting tracers and anti-tumor biomedical research.