Synthesis and fluorescent properties investigation of CdSe quantum dots embedded in a biopolymer based on poly((2-dimethylaminoethyl) methacrylate) grafted onto κ-Carrageenan

In this work, CdSe quantum dots (CdSe QDs) were successfully synthesized and embedded in a biopolymer based on poly((2-dimethylaminoethyl) methacrylate) grafted onto kappa-Carrageenan (κC) via a facile process. The synthesized samples were studied by transmission electron microscopy (TEM) and it showed that the CdSe quantum dots have an average size of around 3.5 nm which were dispersed in the biopolymer matrix. Fourier transform infrared spectrum (FT-IR) was used to characterize the functional groups on the surface of QDs and the structure of biopolymer samples. UV–vis and FL spectra were employed to study the optical properties of QDs before and after ligand exchange with modified κ-Carrageenan biopolymers. The obtained samples showed significant improvement in their thermal behavior as indicated by thermo gravimetric analysis (TGA). Lastly, the effect of some factors on the fluorescent properties of CdSe quantum dots has been investigated to obtain QDs with highest fluorescent intensities.

A novel approach for obtaining the water soluble and highly stable CdSe-κC-g-PDMA QDs via a facile process at room temperature and in water is described.Figure optionsDownload as PowerPoint slideHighlights
► The conjugated CdSe-biopolymer supramolecules are prepared.
► They are achieved via incorporation of CdSe QDs onto a completely eco-friendly biopolymer via a facile process.
► The biopolymer is based on poly((2-dimethylaminoethyl) methacrylate) grafted onto κ-Carrageenan polysaccharide.
► The CdSe-biopolymer QDs show great optical properties and stability after surface passivation.