Non-Cytotoxic Quantum Dot–Chitosan Nanogel Biosensing Probe for Potential Cancer Targeting Agent

Nanomaterials

Tyler Maxwell²  Tahmina Banu¹  Edward Price²  Jeremy Tharkur¹  Maria Gabriela Nogueira Campos¹  Andre Gesquiere²  Swadeshmukul Santra² 

[1] NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA; E-Mails:;Department of Chemistry, University of Central Florida, 4000 Central Florida Blvd., Orlando, FL 32816, USA; E-Mails:

关键词: quantum dot;    biosensor;    chitosan;    drug delivery;    cancer;    nanogel;   

DOI  :  10.3390/nano5042359

来源: mdpi

【 摘 要 】

Quantum dot (Qdot) biosensors have consistently provided valuable information to researchers about cellular activity due to their unique fluorescent properties. Many of the most popularly used Qdots contain cadmium, posing the risk of toxicity that could negate their attractive optical properties. The design of a non-cytotoxic probe usually involves multiple components and a complex synthesis process. In this paper, the design and synthesis of a non-cytotoxic Qdot-chitosan nanogel composite using straight-forward cyanogen bromide (CNBr) coupling is reported. The probe was characterized by spectroscopy (UV-Vis, fluorescence), microscopy (Fluorescence, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Dynamic Light Scattering. This activatable (“OFF”/“ON”) probe contains a core–shell Qdot (CdS:Mn/ZnS) capped with dopamine, which acts as a fluorescence quencher and a model drug. Dopamine capped “OFF” Qdots can undergo ligand exchange with intercellular glutathione, which turns the Qdots “ON” to restore fluorescence. These Qdots were then coated with chitosan (natural biocompatible polymer) functionalized with folic acid (targeting motif) and Fluorescein Isothiocyanate (FITC; fluorescent dye). To demonstrate cancer cell targetability, the interaction of the probe with cells that express different folate receptor levels was analyzed, and the cytotoxicity of the probe was evaluated on these cells and was shown to be nontoxic even at concentrations as high as 100 mg/L.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.