Luminescent Nanoparticles of Polyelectrolyte Complex of Chitosan With Carrageenan as Perspective Multifunctional Vancomycin Delivery Systems

Nanoparticles of a polyelectrolyte complex of chitosan and κ-carrageenan containing core–shell quantum dots of CdS/ZnS were obtained and characterized as potential biocompatible luminescent delivery systems for the antibiotic vancomycin with an encapsulation efficiency of 95–97%. Quantum dots were obtained by a colloidal synthesis method and hydrophilized with mercaptopropionic acid. The effect of vancomycin encapsulated in particles of the polyelectrolyte complex on the luminescent properties of CdS/ZnS quantum dots was studied. The capabilities of the synthesized quantum dots as analytical nanosensors for determine the incorporation and release of vancomycin from the developed carriers based on their luminescence quenching were demonstrated. The binding of vancomycin to albumin as a model of blood protein was studied, the composition of the complex ([vancomycin]: [albumin] = 1.0 : 2.0) and its stability constant (βκ = 6.0 ⋅ 104 M−1) were determined. Analysis of kinetic data on the release of vancomycin from polymer carriers under in vitro conditions into albumin and tris-buffer solutions within the framework of the Korsmeyer–Peppas mathematical model showed that the release of the antibiotic is controlled by both diffusion and relaxation of the polymer matrix.