title: Sonosynthesis of gold nanoparticles from a geranium leaf extract.
abstract: A rapid in situ biosynthesis of gold nanoparticles (AuNPs) is proposed in which a geranium (Pelargonium zonale) leaf extract was used as a non-toxic reducing and stabilizing agent in a sonocatalysis process based on high-power ultrasound. The synthesis process took only 3.5 min in aqueous solution under ambient conditions. The stability of the nanoparticles was studied by UV-Vis absorption spectroscopy with reference to the surface plasmon resonance (SPR) band. AuNPs have an average lifetime of about 8 weeks at 4 °C in the absence of light. The morphology and crystalline phase of the gold nanoparticles were characterized by transmission electron microscopy (TEM). The composition of the nanoparticles was evaluated by electron diffraction and X-ray energy dispersive spectroscopy (EDS). A total of 80% of the gold nanoparticles obtained in this way have a diameter in the range 8-20 nm, with an average size of 12±3 nm. Fourier transform infrared spectroscopy (FTIR) indicated the presence of biomolecules that could be responsible for reducing and capping the biosynthesized gold nanoparticles. A hypothesis concerning the type of organic molecules involved in this process is also given. Experimental design linked to the simplex method was used to optimize the experimental conditions for this green synthesis route. To the best of our knowledge, this is the first time that a high-power ultrasound-based sonocatalytic process and experimental design coupled to a simplex optimization process has been used in the biosynthesis of AuNPs.
authors: Departamento de Química Física, Instituto Universitario de Investigación en Microscopía Electrónica y Materiales (IMEYMAT), Facultad de Ciencias, Universidad de Cádiz, Avda. República Saharaui, S/N, 11510 Puerto Real, Cádiz, Spain; Departamento de Química Analítica, Instituto Universitario de Investigación en Microscopía Electrónica y Materiales (IMEYMAT), Facultad de Ciencias, Universidad de Cádiz, Avda. República Saharaui, S/N, 11510 Puerto Real, Cádiz, Spain.
authors: M
authors: M
authors: Franco-Romano
authors: Departamento de Química Física, Instituto Universitario de Investigación en Microscopía Electrónica y Materiales (IMEYMAT), Facultad de Ciencias, Universidad de Cádiz, Avda. República Saharaui, S/N, 11510 Puerto Real, Cádiz, Spain. Electronic address: almoraima.gil@uca.es.
authors: M L A
authors: ML
authors: Gil
authors: Departamento de Química Analítica, Instituto Universitario de Investigación en Microscopía Electrónica y Materiales (IMEYMAT), Facultad de Ciencias, Universidad de Cádiz, Avda. República Saharaui, S/N, 11510 Puerto Real, Cádiz, Spain.
authors: J M
authors: JM
authors: Palacios-Santander
authors: Departamento de Ciencias de los Materiales e Ingeniería, Instituto Universitario de Investigación en Microscopía Electrónica y Materiales (IMEYMAT), Metalúrgica y Química Inorgánica, Facultad de Ciencias, Universidad de Cádiz, Avda. República Saharaui, S/N, 11510 Puerto Real, Cádiz, Spain.
authors: J J
authors: JJ
authors: Delgado-Jaén
authors: Departamento de Química Analítica, Instituto Universitario de Investigación en Microscopía Electrónica y Materiales (IMEYMAT), Facultad de Ciencias, Universidad de Cádiz, Avda. República Saharaui, S/N, 11510 Puerto Real, Cádiz, Spain.
authors: I
authors: I
authors: Naranjo-Rodríguez
authors: Departamento de Química Analítica, Instituto Universitario de Investigación en Microscopía Electrónica y Materiales (IMEYMAT), Facultad de Ciencias, Universidad de Cádiz, Avda. República Saharaui, S/N, 11510 Puerto Real, Cádiz, Spain.
authors: J L
authors: JL
authors: Hidalgo-Hidalgo de Cisneros
authors: Departamento de Química Analítica, Instituto Universitario de Investigación en Microscopía Electrónica y Materiales (IMEYMAT), Facultad de Ciencias, Universidad de Cádiz, Avda. República Saharaui, S/N, 11510 Puerto Real, Cádiz, Spain.
authors: L M
authors: LM
authors: Cubillana-Aguilera
mesh_terms: D002384:Catalysis; D060326:Chemistry Techniques, Synthetic; D031315:Geranium / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry*; D013010:Sonication / Q000295:instrumentation / Q000379:methods*
chemical_list: D010936:Plant Extracts; D006046:Gold
keywords: Biosynthesis; Experimental design; Gold nanoparticles; Simplex; Sonocatalysis; Ultrasound