Introduction- Electrospinning has the unique ability to produce nanofibres of different materials in various fibrous assemblies. Electrospinning was first patented in the US in 1902. However, the process was largely forgotten until the 1990s.
Types of Electrospinning :-
Although fibers produced by different electrospinning methods have attracted increasing attention in the field of biomedical applications, challenges persist for the selection of an appropriate method, as well as for optimizing multiple parameters to generate robust cargo loaded nanofibres. Electrospinning techniques can be classified into five categories:
1. Blend electrospinning
2. Coaxial electrospinning
3. Emulsion electrospinning
4. Melt electrospinning
5. Gas jet electrospinning
Application of electrospinning techniques in agriculture
Electrospinning in Pest control :-
A network of fibers from electrospinning instead of powder or aerosols provides several advantages for controlling and keeping out pests. The fibrous network may be used as a physical barrier to keep out the pests or it may be loaded with active chemicals. The amount of chemicals needed may be reduced as the fibre matrix protects the loaded chemicals from the environment while slowly releasing them for pest management. The mesh of fibers from electrospinning can be easily sprayed and this forms a fibrous network across neighbouring plants. This functions as a physical and chemical barrier against potential pests.
Fertilizer Application :-
Fertilizers have been added into the solution for electrospinning into fibers. Depending on the polymer carrier and the structure of the fibers, the release rate of the fertilizers may be tailored. A network of fibers is much less likely to be washed away than particles. This will reduce the amount of fertilizer loss by the farmer and at the same time prevent pollution of the waterways due to fertilizer run-offs.
Pollution control :-
Agriculture with its use of fertilizers, pesticides, herbicides and fungicides to improve yield of the crops is often a source of pollution and may sometimes be detrimental to the crops itself. Herbicides while meant to reduce growth of weeds, may act against seed germination or seedlings if the water source is contaminated with it.
Pesticides and fungicides residues are always a concern for consumers while excess fertilizers washed into the streams and rivers may disrupt its ecosystem.
Drug Delivery :-
Electrospun fibers have been tested for drug delivery in various medical applications. A similar strategy may be employed for farm animals. The potential use of electrospun progesterone-loaded zein fibers for estrus synchronization of bovines.
Seed Development :-
The importance of understanding seed development has led to research using various methods to understand environmental stimuli on root growth. In the use of transparent microfluidic channel for studying root growth, one main challenge is to regulate the temperature on seed development. Comparing the insulation property of electrospun membranes with cast membranes, the former was able to provide much better insulation for the same thickness. The level of insulation can be controlled easily by varying the duration of fiber deposition which directly impacts membrane thickness. With this, they were able to show the growth rate variation of Arabidopsis seeds at different temperatures.
In-vitro pollen germination :-
Pollen germination in vitro is useful for determining pollen viability and other in vitro tests. The medium for supporting pollen germination typically comes in the form of liquid or agar gel. Electrospun membrane may be used as a physical support for pollen germination on liquid medium.
Electrospinning is a promising technology for manufacturing nanofibres from the laboratory to industrial level. Nanomaterials possess a large surface area and enhanced porosity, which are advantages for drug delivery and many other biomedical applications. Electrospinning is the most widely used technique because of its promising results. Electrospun nanofibres have attracted much attention due to their biocompatibility, adhesiveness, sterile nature and their efficiency in diverse applications. Currently, nanofibres are considered suitable platform for wound dressing materials, drug delivery systems, filtration membranes, catalysts for reduction and so on.
Dr. Monika Karnawat, Associate Professor, School of Agriculture Sciences, Career Point University, Kota