Engineering and use of proteinoid polymers and nanocapsules containing agrochemicals

Abstract

To address global challenges such as population growth and climate change, introduction of new technologies and innovations in agriculture are paramount. Polymer-based formulations of agrochemicals have received much attention in recent years, and there is strong motivation to develop agrochemicals that are not harmful to the environment. Proteinoid polymers are produced by thermal step-growth polymerization of natural and unnatural amino acids. Under suitable gentle conditions, the proteinoid polymers may self-assemble to form nano-sized hollow proteinoid nanoparticles (NPs) of a relatively narrow size distribution. Agrochemical molecules may be encapsulated within these hollow proteinoid NPs, integrated in the crude proteinoid shell, or bound covalently/physically to the NP surface. In the present manuscript we prepared and characterized four model proteinoid polymers and NPs: P(KEf), P(KF), P(EWH-PLLA) and P(KWH-PLLA), where Ef denotes the unnatural herbicidal amino acid glufosinate. The NPs were fluorescently labeled and loaded with agrochemicals such as the plant hormone auxin. In addition, the NP surface was hydrophobized by covalent conjugation of dodecyl aldehyde via its surface primary amine groups. Following treatment of the plants with the different fluorescent-labeled NPs, fluorescent microscopic techniques enabled to localize the NPs and observe the accumulation in the plant’s vascular system. Next, using genetically modified plants, which express fluorescent protein and are responsive to the level of auxin, we demonstrated the possibility to deliver encapsulated agrochemicals into cells. We also illustrated that the proteinoid NPs are non-toxic to human umbilical vein endothelial cells, and apart from P(KEf) also to lettuce plants.

Towards proteinoid computers

“…The proteinoids can be prepared by heating mixtures of amino acids at 190 o C under a nitrogen blanket, mechanically stirred with water and filtered [82,59,89,54]. Microspheres assembled from copoly(asp, glu), copoly(asp, glu) complexed with copoly(asp, glu, arg, his).…”

Guest Edited Collection: Nanotechnology in agriculture

“…There are also 'Other applications and effects' that have been tested and developed, such as efficient delivery of plant hormones and growth regulators which positively affect crop development 6,19 , or active molecules that are able to modulate stress responses 5…”

“…There are also ‘Other applications and effects’ that have been tested and developed, such as efficient delivery of plant hormones and growth regulators which positively affect crop development 6 , 19 , or active molecules that are able to modulate stress responses 5 . In addition, there are reports about how priming seeds with nanomaterials leads to improved growth and yield in some crops 7 , 20 .…”

Variation in phytochemical properties and expression of key genes involved in biosynthesis of hypericin using nano-capsulated and normal hormones in Hypericum perforatum L

“…Nowadays, the development of nanoparticulate compounds is one of the most important topics in pharmaceutical and food researches to improve their e ciency and functions (Preetz et al, 2008). The use of nanotechnology in agricultural products could play a crucial role for improving agrochemical delivery and nutrient management (Sasson et al, 2020). Among these agrochemicals, nano-hormones production is a novel subject that has not yet been fully performed.…”