Adenosine-Monophosphate-Assisted Homogeneous Silica Coating of Silver Nanoparticles in High Yield

In this study, we propose a novel approach for the silica coating of silver nanoparticles based on surface modification with adenosine monophosphate (AMP). Upon AMP stabilization, the nanoparticles can be transferred into 2-propanol, promoting the growth of silica on the particle surfaces through the standard Stöber process. The obtained silica shells are uniform and homogeneous, and the method allows a high degree of control over shell thickness while minimizing the presence of uncoated NPs or the negligible presence of core-free silica NPs. In addition, AMP-functionalized AgNPs could be also coated with a mesoporous silica shell using cetyltrimethylammonium chloride (CTAC) as a template. Interestingly, the thickness of the mesoporous silica coating could be tightly adjusted by either the silica precursor concentration or by varying the CTAC concentration while keeping the silica precursor concentration constant. Finally, the influence of the silica coating on the antimicrobial effect of AgNPs was studied on Gram-negative bacteria (R. gelatinosus and E. coli) and under different bacterial growth conditions, shedding light on their potential applications in different biological environments.

Descrição

co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007265), as well as the PROTEOMASS Scientific Society General Funds (Portugal) for funding support. I.P.-S. and J.P.-J. acknowledge financial support from Spanish MINECO grant PID2019-108954RB-I00. J.F.-L. thanks the FCT-UNL for the research contract through the Program DL57/2016 Norma Transitória. C.F.-L. acknowledges Xunta de Galicia for a predoctoral scholarship (Programa de axudas á etapa predoutoral). The authors thank Jamila Djafari for their assistance with the design of the graphical abstract. Publisher Copyright: © 2023 by the authors.

Palavras-chave

adenosine monophosphate bactericidal properties mesoporous silica silica coating silver nanoparticles General Chemical Engineering General Materials Science