Jose E. Quiroz-Hernández
◽
Oxana V. Kharissova
◽
Victor E. Aguirre-Arzola
◽
Guillermo C.G. Martinez-Avila
◽
Uziel Castillo-Velazquez
Aims:
To use an agroindustrial waste (orange peels) as a source of polyphenols as a reducing
medium for obtaining silver nanoparticles by greener method.
Background:
Several techniques have been employed for AgNPs synthesis, nevertheless, most of them
involve the use of toxic chemicals in the process. The use of fungi, bacteria, and plant extracts as subtracts
for green synthesis is an ecofriendly alternative, although hypothetic, route for AgNPs large
scale synthesis. In the case of plant extracts, it is believed that polyphenols are the biomolecules responsible
for the reduction and stabilization of the Ag+ ions into AgNPs, being a sustainable and ecological
option; polyphenols could be obtained from plant waste and agroindustrial subproducts.
Objective:
To develop an efficient, greener, and low-cost method of AgNPs production using natural
products.
Methods:
The basic principle of silver nanoparticles synthesis is the interaction in a mixture of silver
nitrate (source of Ag+ ions) and the orange peel extract (reducing and stabilizing agent) under certain
conditions. Five treatments were carried out, evaluating several parameters during AgNPs synthesis
such as pH, orange peel extract-silver nitrate ratio, time and conditions of incubation, irradiation of UV
light, irradiation of microwave, and temperature.
Result:
The synthesis of silver nanoparticles from an agroindustrial waste as the orange peel was successfully
carried out and checked by visual evaluation, UV-Vis spectroscopy, and EDS analysis. The
particle size was estimated between 42.82 nm to 151.75 nm, having a spherical and ovoid morphology.
Discussion:
Through the analysis of several synthesis conditions, it has become possible to establish a
suitable treatment to increase antibacterial yield and evaluate morphology and size traits in order to acquire
the best conditions for a future industrial scale synthesis.
Conclusion:
The orange peel aqueous extract resulted as a great source of polyphenols, allowing the
successful synthesis of silver nanoparticles in mild conditions. Thus, obtained AgNPs revealed an increased
antibacterial effect and potential against Gram-positive bacteria such as Staphyloccocus aureus.
Silver nanoparticles biogenic synthesized using an orange peel extract and their use as an anti-bacterial agent
