Photoacoustic properties of polypyrrole nanoparticles

0545720 - ÚMCH 2022 RIV CH eng J - Journal Article
Keša, P. - Paúrová, Monika - Babič, Michal - Heizer, T. - Matouš, P. - Turnovcová, Karolína - Mareková, Dana - Šefc, L. - Herynek, V.
Photoacoustic properties of polypyrrole nanoparticles.
Nanomaterials. Roč. 11, č. 9 (2021), č. článku 2457. E-ISSN 2079-4991
R&D Projects: GA ČR(CZ) GA18-05200S; GA MŠMT(CZ) LQ1604
Research Infrastructure: Czech-BioImaging II - 90129
Institutional support: RVO:61389013 ; RVO:68378041
Keywords : photoacoustic imaging * polypyrrole * nanoparticles
OECD category: Medical laboratory technology (including laboratory samples analysis; Neurosciences (including psychophysiology (UEM-P)
Impact factor: 5.719, year: 2021
Method of publishing: Open access
https://www.mdpi.com/2079-4991/11/9/2457

Photoacoustic imaging, an emerging modality, provides supplemental information to ultrasound imaging. We investigated the properties of polypyrrole nanoparticles, which considerably enhance contrast in photoacoustic images, in relation to the synthesis procedure and to their size. We prepared polypyrrole nanoparticles by water-based redox precipitation polymerization in the presence of ammonium persulphate (ratio nPy:nOxi 1:0.5, 1:1, 1:2, 1:3, 1:5) or iron(III) chloride (nPy:nOxi 1:2.3) acting as an oxidant. To stabilize growing nanoparticles, non-ionic polyvinylpyrrolidone was used. The nanoparticles were characterized and tested as a photoacoustic contrast agent in vitro on an imaging platform combining ultrasound and photoacoustic imaging. High photoacoustic signals were obtained with lower ratios of the oxidant (nPy:nAPS ≥ 1:2), which corresponded to higher number of conjugated bonds in the polymer. The increasing portion of oxidized structures probably shifted the absorption spectra towards shorter wavelengths. A strong photoacoustic signal dependence on the nanoparticle size was revealed, the signal linearly increased with particle surface. Coated nanoparticles were also tested in vivo on a mouse model. To conclude, polypyrrole nanoparticles represent a promising contrast agent for photoacoustic imaging. Variations in the preparation result in varying photoacoustic properties related to their structure and allow to optimize the nanoparticles for in vivo imaging.
Permanent Link: http://hdl.handle.net/11104/0323109