Preparation and Characterization of Zein-Based Nanoparticles via Ring-Opening Reaction and Self-Assembly as Aqueous Nanocarriers for Pesticides

Abstract

Herein, we prepared and compared two water-soluble amphiphilic zein-based nanocarrier systems with avermectin (AVM) payload to enhance pesticide's water-dispersity, foliage wettability, adhesion, anti-UV, and pH-responsive controlled release property. Ethylene glycol diglycidyl ether (EGDE) and diethanolamine (DEA) were utilized to conjugate with hydrophobic zein via a ring-opening reaction and then encapsulated with AVM via a hydrophobic interaction to fabricate a nanopesticide marked as AVM@Zein-EGDE/DEA. For the sake of further improving the nanocarrier's performance, sodium carboxymethyl cellulose (CMC) was grafted with methyl methacrylate (MMA) and 2-hydroxyethyl methacrylate (HEMA) to form a kind of copolymer CMC-g-P(HEMA-MMA), which was applied to conjugate with Zein-EGDE via a ring-opening reaction. Likewise, another nanopesticide system named AVM@Zein-EGDE/CMC-g-P(HEMA-MMA) was obtained through hydrophobic interactions as well as the electrostatic effect. Various techniques were utilized to confirm chemical interaction, thermal behavior, structural characteristics, and stability. The results showed that AVM encapsulated in Zein-EGDE/CMC-g-P(HEMA-MMA) possessed a larger particle size with an average value of 180−254 nm than AVM loaded in Zein-EGDE/DEA with 144−175 nm but had better stability in aqueous solution. Also, AVM loaded in Zein-EGDE/CMC-g-P(HEMA-MMA) enhanced the encapsulation efficiency, and both of them exhibited excellent pH-responsive sustained release behavior. Besides, the former improved wettability on a cucumber leaf surface and enhanced adhesion ability compared to AVM@Zein-EGDE/DEA because of CMC-g-P(HEMA-MMA) with hydrophobic segments. Similarly, anti-UV performance was also enhanced owing to CMC-g-P(HEMA-MMA) as an additional protective layer. More importantly, the encapsulation of Zein-EGDE/DEA and Zein-EGDE/CMC-g-P(HEMA-MMA) as protective barriers for AVM still retained a similar toxicity level. Overall, we demonstrated the proof of concept for the application of amphiphilic zeinbased nanomaterials as aqueous nanocarriers for hydrophobic pesticides.

MXene (Ti3C2) Based Pesticide Delivery System for Sustained Release and Enhanced Pest Control

“…The wettability and retention of formulations on leaves surface may affect the bioactivity of pesticides. Herein, the contact angle was used to evaluate the wetting characteristics and adhesion ability of AV@Ti 3 C 2 formulation. , As Figure shows, the contact angles of water and AV@Ti 3 C 2 on the surface of maize leaf are about 94.8°and 59.1°, respectively. The low contact angle indicates the good adhesion ability and spreadability of AV@Ti 3 C 2 nanoformulation on the maize leaves surface, which will increase the adsorption and deposition of pesticide …”

A stable polyamine‐modified zein‐based nanoformulation with high foliar affinity and lowered toxicity for sustained avermectin release

“…As a coupling agent, EGDE reacts with the amino group of zein at room temperature to introduce epoxy groups obtaining zein-EGDE. 26 Excess EGDE in the reactor was used to connect different PEI-EDA, which were grafted to zein-EGDE (Fig. 1).…”

Fe3O4 Magnetic Cores Coated with Metal–Organic Framework Shells as Collectable Composite Nanoparticle Vehicles for Sustained Release of the Pesticide Imidacloprid

“…3−5 Pesticide loaded into nanoparticles often exhibits improved bioactivity due to its more uniform spraying over the leaves, easier breakdown of water protection barriers, and increased affinity of pesticides to the targets, compared with traditional formulations. 6 Up to date, a plethora of pesticide delivery systems have been developed with the help of various materials, including mesoporous silica, 7,8 clay mineral, 9 carbon nanomaterials, 10,11 protein, 12 synthetic polymers, 13 and so on. Porous-structured inorganic materials like mesoporous silica and silicate are often favored due to their low production cost, biocompatibility, and high loading capacity.…”

“…However, about 90% of pesticides are usually lost or decomposed due to their photolysis, volatilization, leaching, and off-targeting, resulting in the overuse of pesticides, which ultimately poses a huge threat toward the environment and ecological and human health. , Therefore, the development of a nanopesticide delivery system has drawn abundant attention in terms of its prolonged effective release duration, reduced initial burst release, and decreased pesticide dosage. − Pesticide loaded into nanoparticles often exhibits improved bioactivity due to its more uniform spraying over the leaves, easier breakdown of water protection barriers, and increased affinity of pesticides to the targets, compared with traditional formulations . Up to date, a plethora of pesticide delivery systems have been developed with the help of various materials, including mesoporous silica, , clay mineral, carbon nanomaterials, , protein, synthetic polymers, and so on. Porous-structured inorganic materials like mesoporous silica and silicate are often favored due to their low production cost, biocompatibility, and high loading capacity. , For instance, Cao and co-workers developed a novel urease-responsive silica-IPTS-PEI microcapsule to prevent thermal degradation and photodegradation of pendimethalin and achieve sustained pesticide release .…”