Star-Block Copolymers as Templates for the Preparation of Stable Gold Nanoparticles
-
Filali, Mariam; Meier, Michael; Schubert, Ulrich S.; Gohy, Jean-Francois
- Abstract:
- Gold nanoparticles of improved stability against aggregation were prepared using poly(ethylene oxide)-
block-poly(-caprolactone) (PEO-b-PCL) star-block copolymers.Afive-arm star-shaped macroinitiator (PEO)
was utilized for the automated parallel controlled ring-opening polymerization of -caprolactone to prepare
a series of PEO-b-PCL star-block copolymers with a constant PEO core linked to PCL blocks of variable
length. The PEO core was swelled with KAuCl4 inN,N-dimethylformamide (DMF), and gold nanoparticles
were subsequently obtained by reduction with NaBH4. Since the process was always templated by the
same PEO core for all investigated polymers, the average dimension of the formed gold nanoparticles was
in the same range for all star-block copolymers. In sharp contrast, the size distribution and long-term
stability against aggregation of the gold nanoparticles dispersed in DMF were strongly dependent on the
PCL block length, confirming the role of PCL blocks as stabilizing blocks for these nanoparticles.
- Year:
- 2005
- Type of Publication:
- Article
- Journal:
- Langmuir
- Volume:
- 21
- Pages:
- 7995 - 8000