Glycoglycerolipid-coated F/ZnO quantum dots: A biocompatible amphiphilic formulation for fluorescent nanoprobes

Colloidal quantum dots (QDs) represent a versatile class of luminescent nanomaterials whose physicochemical and interfacial properties can be engineered for advanced bio-related applications. Herein, the wet-precipitation synthesis and surface engineering of ultra-small fluorine-doped ZnO quantum dots (F/ZnO QDs) were proposed and their formulation into stable amphiphilic nanosystems using synthetic glycoglycerolipids. To control aggregation and interfacial behavior, the QDs were first capped with oleylamine and subsequently functionalized through an emulsion-based approach with mono-acyl or di-acyl glycoglycerolipids, yielding double-coated amphiphilic nanoformulations. The resulting materials were extensively characterized by TEM, DLS, zeta-potential measurements, XRD, FTIR/ATR, UV-Vis, and fluorescence spectroscopy, allowing to explore correlations between surface chemistry, colloidal stability, and optical properties. Glycoglycerolipid functionalization led to a marked improvement in aqueous dispersibility and long-term colloidal stability while preserving the enhanced fluorescence induced by fluorine doping. Biological assays confirmed the cytocompatibility of the coated QDs and supported their suitability for further biointerface studies. This work highlights glycoglycerolipid-based amphiphilic coatings as an effective strategy to tailor the surface and colloidal properties of ZnO-based QDs, enabling the development of stable luminescent nanomaterials as biocompatible nanoprobes and for bio-interfacial applications.