Facile Formation of Redox‐Active Totally Organic Nanoparticles in Water by In Situ Reduction of Organic Precursors Stabilized through Aromatic–Aromatic Interactions by Aromatic Polyelectrolytes. Issue 21 (12th September 2016)

• Record Type: Journal Article
• Authors: Flores, Mario E.; Garcés‐Jerez, Pablo; Fernández, Daniel; Aros‐Perez, Gustavo; González‐Cabrera, Diego; Álvarez, Eduardo; Cañas, Ignacio; Oyarzun‐Ampuero, Felipe; Moreno‐Villoslada, Ignacio
• Is Part Of: Macromolecular rapid communications. Volume 37:Issue 21(2016)
• Page Start: 1729
• Page End: 1734
• Publication Date: 2016-09-12
• Subjects: dyes -- pigments -- hydrogels -- nanoparticles -- pigments -- polyelectrolytes -- sensors; Macromolecules -- Periodicals; Polymers -- Periodicals; Chemistry -- Periodicals; 547.705
• DOI: 10.1002/marc.201600339
• Languages: English
• ISSNs: 1022-1336

Abstract

Abstract : The formation of redox‐active, totally organic nanoparticles in water is achieved following a strategy similar to that used to form metal nanoparticles. It is based on two fundamental concepts: i) complexation through aromatic–aromatic interactions of a water‐soluble precursor aromatic molecule with polyelectrolytes bearing complementary charged aromatic rings, and ii) reduction of the precursor molecule to achieve stabilized nanoparticles. Thus, formazan nanoparticles are synthesized by reduction of a tetrazolium salt with ascorbic acid using polyelectrolytes bearing benzene sulfonate residues of high linear aromatic density, but cannot be formed in the presence of nonaromatic polyelectrolytes. The red colored nanoparticles are efficiently encapsulated in calcium alginate beads, showing macroscopic homogeneity. Bleaching kinetics with chlorine show linear rates on the order of tenths of milli­meters per minute. A linear behavior of the dependence of the rate of bleaching on the chlorine concentration is found, showing the potential of the nanoparticles for chlorine sensing. Abstract : Redox‐active, totally organic nano­particles in water are synthesized by complexation through aromatic–aromatic interactions of water‐soluble precursor aromatic molecules with polyelectrolytes bearing complementary charged aromatic rings, and subsequent reduction of the precursor molecule. Colored formazan nanoparticles obtained from tetrazolium salts by this method are efficiently encapsulated in calcium alginate beads, which show potential for sensing in‐time maintained stimuli.