Water-assisted synthesis of stable and multicolored CsPbX₃@SiO₂ core-shell nanoparticles as fluorescent probes for biosensing

Autores de IIS La Fe

• Sergi Morais Ezquerro

  Autor

• Ángel Maquieira Catalá

  Autor

Participantes ajenos a IIS La Fe

• Collantes, Cynthia
• Teixeira, William
• Gonzalez-Pedro, Victoria
• Banuls, Maria-Jose
• Quintero-Campos, Pedro

Grupos

• Unidad Mixta de Investigación en Nanomedicina y Sensores

  Leader

  Ramón Martínez Máñez

Abstract

Colloidal lead halide perovskite nanocrystals are highly luminescent materials with great promise as fluorescent probes in biosensing as long as their intrinsic instability in aqueous media is effectively addressed. In this study, we successfully prepared stable and multicolored CsPbX3@SiO2 (X = Cl/Br, Br and I) core-shell nanoparticles through a simple method based on the water-induced transformation of Cs4PbX6 into CsPbX3, combined with sol-gel procedures. We observed that the concentration of the Cs4PbX6 precursor plays a crucial role in the formation of isolated nanospheres with uniform silica coating and in controlling the number of core-free particles. Furthermore, our research expands this approach to other halide compositions, resulting in multicolored core-shell nanoparticles with emission wavelengths ranging from 490 to 700 nm, average sizes below 30 nm, and photoluminescence quantum yields close to 60%. Unlike in previous reports, the silica coating boosts the photoluminescence quantum yields compared to uncoated counterparts and provides increased structural stability for more than four days. Moreover, a controlled thermal treatment confers water stability to the as-synthesized nanoparticles. To establish the feasibility of the developed materials as fluorescent probes, we successfully demonstrated their specific recognition of a humanized antibody (omalizumab) used in treating patients with severe allergic asthma. This work paves the way to develop in vitro tests using CsPbX3@SiO2 core-shell nanoparticles as fluorogenic probes.

Keywords

• HALIDE PEROVSKITE NANOCRYSTALS; CS4PBBR6 NANOCRYSTALS; I NANOCRYSTALS; CSPBBR3; TRANSFORMATION; CSPBX3; BR; CL; EFFICIENT