ZnO Quantum Dots

This section focuses on the preparation of novel ZnO-based nanomaterials. Quantum Dots (QDs) available on the market at present contain heavy metals, which limits their use in human organism. A promising alternative are however biocompatible ZnO nanoparticles (NPs). Most of chemical methods of the synthesis of ZnO nanostructures are based on inorganic processes between zinc salts and alkaline metal hydroxides.3 More recent methods include the use of organometallic zinc compounds.Błąd: Nie znaleziono źródła odwołania The main disadvantages of above-mentioned methods lie in the agglomeration processes of these systems. Therefore, a great challenge nowadays is the stabilization of NPs by capping ligands or protecting polymer shells. In the framework of our investigations we develop alternative methods that provide convenient access to functionalized ZnO NPs.

Engineering nanocrystalline ZnO capped with multifunctional ligands

The ligand molecules bound to the nanoparticle surface not only control the growth of the particles during synthesis, but also prevent the aggregation of the nanoparticles.1 We are able to obtain ZnO NPs stabilized by different capping ligands from well-defined organozinc precursors. The synthesis of the nanoparticles is based on the controlled reactions of organometallic precursors with O2, H2O or air. Rational design and preparation of organozinc precursors with various ligands with multi-functional characteristics may contribute to high efficiency and accuracy in ZnO structure tailoring. The control over these factors will lead to QDs with required physicochemical properties and functionality on their surface (e.g., amide or amine groups which are very convenient coupling moieties for biomolecules) and their further conjugation with drugs, synthetic or natural macromolecules, proteins and antibodies. The morphology and physico-chemical properties of the studied systems will be investigated.

Engineering ZnO nanoparticles stabilized by in situ generated polymers

Currently, an intensive research towards the use of polymers as stabilizers of NPs can be observed. However, most of the reported works rely on addition of polymers into solutions containing as-prepared ZnO NPs, thus forming inorganic-organic blends.2 Other strategies employ radical polymerization process to produce polymer matrices as stabilizers.3 Extremely important issue is to obtain bio‑compatible polymeric shells composed of polymers permitted by US Food and Drug Administration and these include poly(ethylene glycol), polylactide, poly(ε-caprolactone), polyglycolide and their copolymers. Recently, we invented novel route of the synthesis of ZnO QDs stabilized by in-situ generated polymers. Our strategy reached high level of applicability as a convenient and attractive route to polymer-coated ZnO nanoparticles.

Encapsulation of ZnO nanoparticles with selected macro- and bioactive molecules

Considerable efforts are nowadays taken to stabilize biocompatible ZnO NPs in aqueous solutions and provide the required functionality onto their surface. Therefore we broadened our investigations on the control of nucleation and growth processes of nanosized ZnO by using macrocyclic encapsulating agents. We also utilize selected model proteins as well as drugs to construct bioconjugates with prepared ZnO QDs through non-covalent and covalent interactions.