Gold Nanostars Bioconjugation for Selective Targeting and SERS Detection of Biofluids

Year: 2021

Authors: Dallari C., Capitini C., Calamai M., Trabocchi A., Pavone F.S., Credi C.

Autors Affiliation: European Laboratory for non-linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Florence, 50019, Italy; Department of Physics, University of Florence, Sesto Fiorentino, Florence, 50019, Italy; National Institute of Optics -National Research Council (CNR-INO), Sesto Fiorentino, Florence, 50019, Italy; Department of Chemistry “Ugo Schiff”, University of Florence, Sesto Fiorentino, Florence, 50019, Italy

Abstract: Gold nanoparticles (AuNPs) show physicochemical and optical functionalities that are of great interest for spectroscopy-based detection techniques, and especially for surface enhanced Raman spectroscopy (SERS), which is capable of providing detailed information on the molecular content of analysed samples. Moreover, the introduction of different moieties combines the interesting plasmonic properties of the AuNPs with the specific and selective recognition capabilities of the antibodies (Ab) towards antigens. The conjugation of biomolecules to gold nanoparticles (AuNPs) has received considerable attention for analysis of liquid samples and in particular biological fluids (biofluids) in clinical diagnostic and therapeutic field. To date, gold nanostars (AuNSts) are gaining more and more attention as optimal enhancers for SERS signals due to the presence of sharp branches protruding from the core, providing a huge number of “”hot spots””. To this end, we focused our attention on the design, optimization, and deep characterization of a bottom up-process for (i) AuNPs increasing stabilization in high ionic strength buffer, (ii) covalent conjugation with antibodies, while (iii) retaining the biofunctionality to specific tag analyte within the biofluids. In this work, a SERS-based substrate was developed for the recognition of a short fragment (HA) of the hemagglutinin protein, which is the major viral antigen inducing a neutralizing antibody response. The activity and specific targeting with high selectivity of the Ab- AuNPs was successfully tested in transfected neuroblastoma cells cultures. Then, SERS capabilities were assessed measuring Raman spectra of HA solution, thus opening interesting perspective for the development of novel versatile highly sensitive biofluids sensors.

Journal/Review: NANOMATERIALS

Volume: 11 (3)      Pages from: 665-1  to: 665-16

More Information: This research was funded by Doptoscreen project “Fondo di Beneficenza Intesa San Paolo 2019” grant number B/2019/0289, and by the European Union´s Horizon 2020 research and innovation programme under grant agreement No 654148 Laserlab-Europe. The APC was funded by Doptoscreen project “Fondo di Beneficenza Intesa San Paolo 2019” grant number B/2019/0289.
KeyWords: gold nanoparticles, gold nanostars, surface-enhanced Raman spectroscopy, SERS, Bioconjugation, neuroblastoma cells, hemagglutinin biofluids
DOI: 10.3390/nano11030665