Optimization and Characterization of Biocompatible Oil-in-Water Nanoemulsion for Pesticide Delivery

Abstract

The formation of promising oil-in-water nanoemulsion suitable for pesticide delivery has been achieved by using methyl laurate as oil phase, and alkyl polyglycoside (APG) and polyoxyethylene 3-lauryl ether (C12E3) as mixed surfactant. Effects of APG and C12E3 mixing ratios, oil weight fraction, and total surfactant concentration on droplet size and distribution of the nanoemulsion were systematically investigated. Long-term stabilities of the nanoemulsions prepared with various surfactant mixing ratios were assessed by measuring droplet size at different time intervals; the results indicated that the main driving force for droplet size increase over time was Ostwald ripening. On this basis, a practical water-insoluble pesticide β-cypermethrin (β-CP) was incorporated into two optimized nanoemulsion systems to demonstrate potential applications. The results of dynamic light scattering (DLS) and transmission electron microscopy (TEM) measurements showed that the nanoemulsions had a nearly monodisperse droplet size distribution (PDI < 0.2) and incorporation of β-CP had no notable effect on the size and stability of the nanoemulsions. For consideration of practical application, dilution stability and spreading properties of the pesticide-loaded nanoemulsion were studied by DLS, contact angle, and dynamic surface tension, respectively. The nanoemulsion was still homogeneous after dilution, although destabilization in droplet size was observed by DLS. The results of contact angle and dynamic surface tension demonstrated the excellent spreading performance of the optimized nanoemulsion.

Preparation of biodiesel oil-in-water nanoemulsions by mixed surfactants for bifenthrin formulation

“…11. The linear variation of r 3 as a function of time indicated that Ostwald ripening was the driving force for instability, which was similar to the results obtained by Du et al 44 It was clearly illustrated that the slope increased with the increase in mR OS , which meant that the more stable nanoemulsions were formed with higher surfactant concentrations. These results were in agreement with previous research results.…”

Bio-Based Nanoemulsion Formulations Applicable in Agriculture, Medicine, and Food Industry

“…The similar herbicidal activities of NE and the commercial formulation, even with the lower NE deposition, could be attributed to potentiation of the biological activity when glyphosate was formulated as NE. In another paper, Du et al (2016) described the preparation and characterization of O/W NEs using laurate as oily phase and a mixture of two surfactants, alkyl polyglycoside (AL) and polyoxyethylene 3-lauryl ether (PLE). In order to evaluate the potential application of the NEs a model insoluble molecule, β-cypermethrin, was incorporated into the NEs.…”

Formulation and physicochemical properties of promising avermectin microemulsion with biodegradable surfactant and oil

“…[30] Second, cosurfactant may diffuse from the interface film into the water phase upon dilution, leading the increase of free energy and decrease of interfacial film strength. [31] The droplet of the oil phase therefore get coalescence to reduce the free energy and interfacial area. Once the systems reach new balance again, the droplet size tend to stable with time.…”