Aerogelation of Polymer-Coated Photoluminescent, Plasmonic, and Magnetic Nanoparticles for Biosensing Applications

authored by

Laura Altenschmidt, Sara Sánchez-Paradinas, Franziska Lübkemann, Dániel Zámbó, Abuelmagd M. Abdelmonem, Henrik Bradtmüller, Atif Masood, Irene Morales, Patricia de la Presa, Alexander Knebel, Miguel Angel García García-Tuñón, Beatriz Pelaz, Karen D.J. Hindricks, Peter Behrens, Wolfgang J. Parak, Nadja C. Bigall

Abstract

Macroscopic materials with nanoscopic properties have recently been synthesized by self-assembling defined nanoparticles to form self-supported networks, so-called aerogels. Motivated by the promising properties of this class of materials, the search for versatile routes toward the controlled assembly of presynthesized nanoparticles into such ultralight macroscopic materials has become a great interest. Overcoating procedures of colloidal nanoparticles with polymers offer versatile means to produce aerogels from nanoparticles, regardless of their size, shape, or properties while retaining their original characteristics. Herein, we report on the surface modification and assembly of various building blocks: photoluminescent nanorods, magnetic nanospheres, and plasmonic nanocubes with particle sizes between 5 and 40 nm. The polymer employed for the coating was poly(isobutylene-alt-maleic anhydride) modified with 1-dodecylamine side chains. The amphiphilic character of the polymer facilitates the stability of the nanocrystals in aqueous media. Hydrogels are prepared via triggering the colloidally stable solutions, with aqueous cations acting as linkers between the functional groups of the polymer shell. Upon supercritical drying, the hydrogels are successfully converted into macroscopic aerogels with highly porous, open structure. Due to the noninvasive preparation method, the nanoscopic properties of the building blocks are retained in the monolithic aerogels, leading to the powerful transfer of these properties to the macroscale. The open pore system, the universality of the polymer-coating strategy, and the large accessibility of the network make these gel structures promising biosensing platforms. Functionalizing the polymer shell with biomolecules opens up the possibility to utilize the nanoscopic properties of the building blocks in fluorescent probing, magnetoresistive sensing, and plasmonic-driven thermal sensing.

Organisation(s)

Institute of Physical Chemistry and Electrochemistry
Institute of Inorganic Chemistry
PhoenixD: Photonics, Optics, and Engineering - Innovation Across Disciplines

External Organisation(s)

Agricultural Research Institute Giza
Karlsruhe Institute of Technology (KIT)
Universidad de Santiago de Compostela
Universität Hamburg
University of Münster
Philipps-Universität Marburg
Complutense University of Madrid (UCM)
Instituto de Cerámica y Consejo Vidrio (CSIC)
Cluster of Excellence Hearing4all

Type

Article

Journal

ACS Applied Nano Materials

Volume

4

Pages

6678-6688

No. of pages

11

Publication date

23.07.2021

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Materials Science(all)

Electronic version(s)

https://doi.org/10.1021/acsanm.1c00636 (Access: Open)