Correlating semiconductor nanoparticle architecture and applicability for the controlled encoding of luminescent polymer microparticles

authored by

Lena Scholtz, J. Gerrit Eckert, Rebecca T. Graf, Alexandra Kunst, K. David Wegner, Nadja C. Bigall, Ute Resch-Genger

Abstract

Luminophore stained micro- and nanobeads made from organic polymers like polystyrene (PS) are broadly used in the life and material sciences as luminescent reporters, for bead-based assays, sensor arrays, printable barcodes, security inks, and the calibration of fluorescence microscopes and flow cytometers. Initially mostly prepared with organic dyes, meanwhile luminescent core/shell nanoparticles (NPs) like spherical semiconductor quantum dots (QDs) are increasingly employed for bead encoding. This is related to their narrower emission spectra, tuneability of emission color, broad wavelength excitability, and better photostability. However, correlations between particle architecture, morphology, and photoluminescence (PL) of the luminescent nanocrystals used for encoding and the optical properties of the NP-stained beads have been rarely explored. This encouraged us to perform a screening study on the incorporation of different types of luminescent core/shell semiconductor nanocrystals into polymer microparticles (PMPs) by a radical-induced polymerization reaction. Nanocrystals explored include CdSe/CdS QDs of varying CdS shell thickness, a CdSe/ZnS core/shell QD, CdSe/CdS quantum rods (QRs), and CdSe/CdS nanoplatelets (NPLs). Thereby, we focused on the applicability of these NPs for the polymerization synthesis approach used and quantified the preservation of the initial NP luminescence. The spectroscopic characterization of the resulting PMPs revealed the successful staining of the PMPs with luminescent CdSe/CdS QDs and CdSe/CdS NPLs. In contrast, usage of CdSe/CdS QRs and CdSe QDs with a ZnS shell did not yield luminescent PMPs. The results of this study provide new insights into structure–property relationships between NP stained PMPs and the initial luminescent NPs applied for staining and underline the importance of such studies for the performance optimization of NP-stained beads.

Organisation(s)

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

External Organisation(s)

BAM Federal Institute for Materials Research and Testing
Freie Universität Berlin (FU Berlin)

Type

Article

Journal

Scientific reports

Volume

14

No. of pages

16

ISSN

2045-2322

Publication date

24.05.2024

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

General

Electronic version(s)

https://doi.org/10.1038/s41598-024-62591-1 (Access: Open)