Polymeric nanocapsules with up-converting nanocrystals cargo make ideal fluorescent bioprobes

Abstract

An innovative approach for up-converting nanoparticles adaptation for bio-related and theranostic applications is presented. We have successfully encapsulated multiple, ~8 nm in size NaYF4 nanoparticles inside the polymeric nanocarriers with average size of ~150 nm. The initial coating of nanoparticles surfaces was preserved due to the hydrophobic environment inside the nanocapsules, and thus no single nanoparticle surface functionalization was necessary. The selection of biodegradable and sugar-based polyelectrolyte shells ensured biocompatibility of the nanostructures, while the choice of Tm3+ and Yb3+ NaYF4 nanoparticles co-doping allowed for near-infrared to near-infrared bioimaging of healthy and cancerous cell lines. The protective role of organic shell resulted in not only preserved high up-converted emission intensity and long luminescence lifetimes, without quenching from water environment, but also ensured low cytotoxicity and high cellular uptake of the engineered nanocapsules. The multifunctionality of the proposed nanocarriers is a consequence of both the organic exterior part that is accessible for conjugation with biologically important molecules, and the hydrophobic interior, which in future application may be used as a container for co-encapsulation of inorganic nanoparticles and anticancer drug cargo.

Nanocontainer in der Analytik

“…[38,67,68] Das heißt, wässrige Markermoleküle kçnnen in hohen Konzen-trationen im inneren Hohlraum eingeschlossen werden, während hydrophobe Stoffe in die Membran interkaliert werden kçnnen. [47,85] Fürm esoporçse Siliciumoxid-Nanocontainer kçnnen die Porengrçße und Geometrie eingestellt und entweder hydrophil oder hydrophob gestaltet werden. [1] Die Hydrophilie des Hohlraums von Polymersomen ist abhängig von der Zusammensetzung der Polymermembran.…”

“…In Gegenwart von Phosph(on)at-Substraten kommt es über die Acylierung der Hydroxygruppe von BODIPY zu einer Bildung von Phosph(on)atestern, was wiederum zu einer intramolekularen N-Alkylierung und damit zu einer Bildung eines bizyklischen Rings führt. [47] Es wurden beispielsweise multifunktionelle Liposomen entwickelt, die mit Er 3+ -u nd Yb 3+ -dotierten, aufkonvertierenden NaGdF 4 -Nanopartikeln im wässrigen Kern und mit DOX in ihrer hydrophoben Membran beladen wurden (Abbildung 11). Dieser Mechanismus ermçglicht die Quantifizierung von chemischen Kampfstoffen, die Phosph(on)atgruppen enthalten, z.…”

Förster Resonance Energy Transfer‐Activated Processes in Smart Nanotheranostics Fabricated in a Sustainable Manner

“…In our previous papers we have shown the templating pathways using self-assembled supramolecular aggregates of surfactantm olecules for efficient encapsulation of inorganic lanthanide-doped NaYF 4 NPs [33] and QDs [34,35] insidet he different types of polymeric nanocontainers. These showed good physical stability, biocompatibility,h igh loading capacity of the active cargo,a nd, thus, provedt hemselves as interesting candidates for bioimaging andt reatment of cancer cells.…”

Smart Nanocontainers: Preparation, Loading/Release Processes and Applications

“…Regarding the loading process, active substances can be loaded into nanocontainers during [66] or after [67][68][69] the synthesis process. After the synthesis, nanocontainers could be directly loaded with the active agents [67][68] or using the assisted loading transfer process [69].…”