Two-step and one-step approach for the in situ synthesis of palladium nanosheets on zein nanoparticle surface using membrane nanoprecipitation

Condello, A. ; Piacentini, E. ; Sebastián, V. (Universidad de Zaragoza) ; Giorno, L.

Resumen: Metal nanostructures with Surface Plasmon Resonance (SPR) properties have garnered interest in applications like optical sensing, photothermal therapy, and optical waveguiding. While synthetic polymers commonly serve as carriers, integrating metal nanostructures with natural-based polymers enhances biocompatibility and biodegradability. With its amine and hydroxyl groups, zein is an ideal material for metal ion interaction enabling efficient surface functionalization of zein nanoparticles (ZNPs). Here, it is demonstrated that zein not only could act as an ideal biopolymeric carrier but also provide an optimal platform for synthesizing anisotropic structures such as palladium nanosheets (PdNS). Two approaches were explored: (i) a two-step approach, involving the preparation of ZNPs via membrane nanoprecipitation (MN) followed by in situ PdNS synthesis using K₂PdCl₄ in a gas-phase carbon monoxide (CO)-confined growth method; and (ii) one-step approach, employing the Pd precursor as the non-solvent during ZNPs nanoprecipitation. For ZNPs-Pd synthesized by the two-step method the influence of variables such as pH, salt, surfactant, and ethanol were evaluated. For one-step approach, to address scalability limitations, ZNPs-Pd nanoprecipitation was performed in a continuous MN process using a 0.2 µm SPG membrane, without using stabilizing agents. TEM imaging confirmed successful, selective PdNS formation on ZNP surfaces without compromising structural integrity. ICP-MS analysis validated the high yield. The ZNPs-Pd demonstrated photothermal activity in the NIR region, achieving temperatures up to 49.6°C. Despite thermal stress, ZNPs-Pd maintained structural stability, marking a significant advancement in the scalable fabrication of biocompatible, photothermally active nanostructures for biomedical and optical applications.

Idioma: Inglés

DOI: 10.1007/s42247-025-01122-8

Año: 2025

Publicado en: Emergent Materials (2025), [13 pp.]
ISSN: 2522-5731

Financiación: info:eu-repo/grantAgreement/ES/MICINN/PDC2022-133866-I00
Financiación: info:eu-repo/grantAgreement/ES/MICINN/PID2021-127847OB-I00

Tipo y forma: Article (Published version)

Área (Departamento): Área Ingeniería Química (Dpto. Ing.Quím.Tecnol.Med.Amb.)