Non-Dependency of In Vitro Fungicidal Efficiency of Copper Nanoparticles against Fusarium oxysporum upon Particle Size

Abstract

Although many papers have consented that the smaller the size of nanoparticles, the higher their efficiency, this paper sheds light on one potential exception of this rule. The paper shows that the in vitro antifungal efficiency of copper nanoparticles against the fusarium wilt pathogen, Fusarium oxysporum, isolated from the infected date palm, Phoenix dactylifera L., is not size-dependent; instead, as it was found that larger copper nanoparticles have better in vitro antifungal efficiency against the fungal pathogen than smaller ones. Copper nanoparticles were synthesized via chemical reduction method at two different pH values, 6.5 and 10.5. Dynamic light scattering was used to measure their particle sizes, which were 345.1 nm and 278.1 nm, respectively. Transmission Electron Microscopy was used to figure out the shapes of nanoparticles, which were polygonal and spherical, respectively. Poison food essay was used to test their in vitro inhibition efficiencies against the fusarium wilt pathogen, F. oxysporum, isolated from the infected date palm, Phoenix dactylifera L., which were 46% and 19%, respectively; at the same concentration. Ultimately, the paper has proposed and discussed a potential reason beyond these unexpected findings, which relies upon the larger surface area to volume ratio of the polygonal copper nanoparticles compared to the spherical copper nanoparticles. The paper concluded that, despite their larger size, polygonal copper nanoparticles have better in vitro antifungal efficiency than spherical copper nanoparticles against F. oxysporum isolated from the infected date palm, Phoenix dactylifera L. at the same concentration.

Green synthesis of copper & copper oxide nanoparticles using the extract of seedless dates

“…Among various types of nanoparticles, copper and copper oxide nanoparticles attract much attention because of their distinguished catalytic, mechanical, magnetic, electric and thermal properties; in addition to their versatile applicability in many fields including agricultural, industrial, environmental and medical applications [2]. Furthermore, copper and copper oxide nanoparticles can be used in catalysis [3], sensors [4], degradation of dyes [5], fungicidal [6,7] and nematicidal [8] applications.…”

Fighting Phytopathogens with Engineered Inorganic-Based Nanoparticles

“…Thus, different susceptibility of the above fungal species in the tested concentrations showed that the efficient dose and incubation time influence the maximum outcome in fungal growth inhibition [ 82 , 83 ]. Much bigger sizes of Cu NPs (345.1 nm) with polygonal shapes showed better antifungal efficiency (46%) against Fusarium oxysporum compared to spherical-shaped Cu NPs (278.1 nm) at the same concentration [ 84 ]. The polygonal shape exhibits a larger surface area to volume ratio, contributing to the antifungal efficiency.…”

“…The polygonal shape exhibits a larger surface area to volume ratio, contributing to the antifungal efficiency. The large size of Cu NPs, comparable to the targeted fungus entities, was considered as increasing the probability of an effect [ 84 ].…”

Optical properties of copper helical nanostructures: the effect of thickness on the SPR peak position

“…In particular, nanostructured Cu films possess distinctive mechanical, thermal, magnetic, electric and catalytic properties, which make them suitable for application in many fields such as industry, medicine, and the environment [29]. Furthermore, Cu thin films could be used in solar cells [30], diodes [31], catalysis [32], high-speed integrated circuits [33,34], sensors [35], fungicidal and nematicidal applications [36][37][38], etc. The grain size control of nanostructured Cu thin films and its effect on physical properties are very important for electronic applications [39], since the deposition process of semiconductors determines the grain size-band gap dependence [40].…”