Star-shaped magnetite@gold nanoparticles for protein magnetic separation and SERS detection

• Type: Article in International Scientific Journal
• Date: 2014

Authors

Pedro Quaresma (Author) Other; Ines Osorio (Author) Other; Goncalo Doria (Author) Other; Patricia A Carvalho (Author) Other; Andre Pereira (Author) FCUP; Judith Langer (Author) Other; Joao Pedro Araujo (Author) FCUP; Isabel Pastoriza Santos (Author) Other; Luis M Liz Marzan (Author) Other; Ricardo Franco (Author) Other; Pedro V Baptista (Author) Other; Eulalia Pereira (Author) FCUP

Journal

Title: RSC Advances

Vol. 4

Pages: 3659-3667

ISSN: 2046-2069

Publisher: Royal Society of Chemistry

Indexing

ISI Web of Knowledge - 87 Citations

Scopus - 94 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-008-K26

DOI: 10.1039/c3ra46762g

Abstract (EN): A novel synthetic methodology for star shaped gold-coated magnetic nanoparticles is reported. The coating is performed in two steps: formation of gold nuclei at the surface of magnetite nanoparticles followed by growth of the gold nuclei into a complete star shaped shell. The star-shaped gold-coated magnetic nanoparticles thus obtained preserve the magnetic properties of the precursor magnetite nanoparticles, e. g. they can be easily separated with a magnet. In addition, the gold coating provides interesting optical properties while simultaneously allowing for biofunctionalization that may be advantageous for biological applications, such as (bio)detection via surface-enhanced Raman spectroscopy (SERS). As a proof-of-concept, a capping agent terminated with a nickel(II)-nitrilotriacetate group showing high affinity for histidine was used to modify the surface of the nanoparticles. The resulting star-shaped nanoparticles were used to selectively capture histidine-tagged maltose-binding protein from a crude cell extract. Finally, the performance of star shaped gold-coated magnetic nanoparticles as SERS platforms was demonstrated through the detection of Raman active dye (Astra Blue).

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9