Ana Maria Percebom

  • Citations Per Year
Learn More
Janus gold nanoparticles are of high interest because they allow directed self-assembly and display plasmonic properties. We succeeded in coating gold nanoparticles with two different polymers that form a Janus shell. The spontaneous segregation of two immiscible polymers at the surface of the nanoparticles was verified by NOESY NMR and most importantly by(More)
Gold patchy nanoparticles (PPs) were prepared under surfactant-free conditions by functionalization with a binary ligand mixture of polystyrene and poly(ethylene glycol) (PEG) as hydrophobic and hydrophilic ligands, respectively. The interfacial activity of PPs was compared to that of homogeneous hydrophilic nanoparticles (HPs), fully functionalized with(More)
Introduction The directed self-assembly of nanoparticles is increasingly relevant in the study of nanotechnology. The ability to control the size, shape, and arrangement of nanoparticles is expected to better control the properties of materials on the nanoscale. Gold nanoparticles have unique optical and electrical properties that give them potential(More)
The presence of acid groups with different pK(a) values in the anionic copolymer poly(4-styrene sulfonic acid-co-maleic acid), P(SS-Ma), allowed the preparation of complex salts with a variable fraction of anionic groups neutralized by cationic surfactant in the copolymer via controlled titration with hexadecyltrimethylammonium hydroxide, C(16)TAOH. Two new(More)
Chemicals Tetrachloroauric acid (HAuCl4∙3H2O), trisodium citrate dehydrate, anhydrous tetrahydrofuran (THF), HPLC-grade chloroform (CHCl3), O-[2-(3mercaptopropionylamino)ethyl]-O’-methylpoly(ethylene glycol) (PEG-SH 5 kDa), tetraethylorthosilicate (TEOS), and ammonium hydroxide solution (NH4OH 29%) were purchased from Sigma-Aldrich. Thiol terminated(More)
Phase behavior of complex salts formed by a cationic surfactant and different ethoxylated polyions was investigated in water and with addition of two n-alcohols of different chain lengths: n-butanol and n-decanol. The polyion possesses a main chain of methacrylic acid randomly grafted with oligo(ethylene oxide) chains. Strong electrostatic interaction(More)
A cationic surfactant and different anionic copolymers randomly grafted with side chains of ethylene oxide were used to prepare stoichiometric complex salts. Variations in the length or proportion of side chains were shown to be responsible for affecting the surfactant phase behavior in water, resulting in the observation of a number of structures(More)
  • 1