Doxorubicin-conjugated D-glucosamine- and folate- bi-functionalised InP/ZnS quantum dots for cancer cells imaging and therapy

Abstract

Nanoscaled quantum dots (QDs), with unique optical properties have been used for the development of theranostics. Here, InP/ZnS QDs were synthesised and functionalised with folate (QD-FA), D-glucosamine (QD-GA) or both (QD-FA-GA). The bi-functionalised QDs were further conjugated with doxorubicin (QD-FA-GA-DOX). Optimum Indium to fatty acid (In:MA) ratio was 1:3.5. Transmission electron microscopy (TEM) micrographs revealed spherical morphology for the QDs (11 nm). Energy-dispersive spectroscopy (EDS) spectrum confirmed the chemical composition of the QDs. MTT analysis in the OVCAR-3 cells treated with bare QDs, QD-FA, QD-GA, QD-FA-GA and QD-FA-GA-DOX (0.2 mg/mL of QDs) after 24 h indicated low toxicity for the bare QDs and functionalised QDs (about 80–90% cell viability). QD-FA-GA-DOX nanoparticles elicited toxicity in the cells. Cellular uptake of the engineered QDs were investigated in both folate receptor (FR)-positive OVCAR-3 cells and FR-negative A549 cells using fluorescence microscopy and FACS flow cytometry. The FA-functionalised QDs showed significantly higher uptake in the FR-positive OVCAR-3 cells, nonetheless the GA-functionalised QDs resulted in an indiscriminate uptake in both cell lines. In conclusion, our findings indicated that DOX-conjugated FA-armed QDs can be used as theranostics for simultaneous imaging and therapy of cancer.

Keywords:

• InP/ZnS quantum dots
• folic acid
• solid tumours
• theranostics
• targeted drug delivery

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

Research Centre for Pharmaceutical Nanotechnology

Biomedicine Institute, Tabriz University of Medical SciencesResearch Center for Pharmaceutical Nanotechnology, Tabriz University of Medical SciencesRCPN-95013

This work was supported (Grant No: RCPN-95013) by the Research Centre for Pharmaceutical Nanotechnology (RCPN), Biomedicine Institute, Tabriz University of Medical Sciences.