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.
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 milli-meters 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.
Instituto de Ciencias Químicas, Facultad de Ciencias, Universidad Austral de Chile, Las Encinas 220, Valdivia, 5110033, Chile.
Mario E
ME
Flores
Instituto de Ciencias Químicas, Facultad de Ciencias, Universidad Austral de Chile, Las Encinas 220, Valdivia, 5110033, Chile.
Pablo
P
Garcés-Jerez
Instituto de Ciencias Químicas, Facultad de Ciencias, Universidad Austral de Chile, Las Encinas 220, Valdivia, 5110033, Chile.
Daniel
D
Fernández
Instituto de Ciencias Químicas, Facultad de Ciencias, Universidad Austral de Chile, Las Encinas 220, Valdivia, 5110033, Chile.
Gustavo
G
Aros-Perez
Instituto de Ciencias Químicas, Facultad de Ciencias, Universidad Austral de Chile, Las Encinas 220, Valdivia, 5110033, Chile.
Diego
D
González-Cabrera
Instituto de Ciencias Químicas, Facultad de Ciencias, Universidad Austral de Chile, Las Encinas 220, Valdivia, 5110033, Chile.
Eduardo
E
Álvarez
Instituto de Ciencias Químicas, Facultad de Ciencias, Universidad Austral de Chile, Las Encinas 220, Valdivia, 5110033, Chile.
Ignacio
I
Cañas
Departamento de Ciencias y Tecnología Farmaceútica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santos Dumont 964, Santiago, 8380494, Chile.
Felipe
F
Oyarzun-Ampuero
Instituto de Ciencias Químicas, Facultad de Ciencias, Universidad Austral de Chile, Las Encinas 220, Valdivia, 5110033, Chile. imorenovilloslada@uach.cl.
Ignacio
I
Moreno-Villoslada
D004573:Electrolytes / Q000737:chemistry*; D005562:Formazans / Q000737:chemistry*; D006841:Hydrocarbons, Aromatic / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D010084:Oxidation-Reduction; D010316:Particle Size; D011108:Polymers / Q000737:chemistry*; D013499:Surface Properties; D013778:Tetrazolium Salts / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
C510333:1,3,5-triphenylformazan; D004573:Electrolytes; D005562:Formazans; D006841:Hydrocarbons, Aromatic; D011108:Polymers; D013778:Tetrazolium Salts; D014867:Water; C009591:triphenyltetrazolium
dyes; hydrogels; nanoparticles; pigments; polyelectrolytes; sensors