Electrospinning and Nanofibers Advantages

1. High surface area to volume ratio
   The nano-dimension of nanofiber naturally gives it a high surface area to volume ratio. This characteristic makes it very attractive in applications where large surface area is desirable such as in sensors and affinity membranes.

   Large surface area of nanofibers membrane have some advantages over cast film. For membrane and film loaded with antibacterial agent, Feng et al (2019) showed that the zone of inhibition of gram-negative (E. coli) and gram-positive (S. aureus) bacteria is significantly greater for nanofiber membrane compared to cast film made of the same material, polylactic acid, and loaded with the same amount of TiO₂ nanoparticles. In applications where rapid drug release is desirable, the high surface area of nanofibers allows fast dissolution. Kwak et al (2019) showed that electrospun fish gelatin (FG) /caffeine membrane took only 1.5s for total disintegration in water but took 40 s in solvent cast film form. On wetted sponge, total disintegration of electrospun FG/caffeine membrane took 5 s but solvent cast film maintained in gel state until 3 minutes due to inadequate water absorption for total disintegration.

   In theory, particles have a larger surface area than fibers, however, measured surface of nanofibers often showed higher surface area than the same material in powder form. This may be attributed to the tendency of small particles to aggregate. Nanofibers in membrane form is also more convenient to use for many applications. Wang et al (2022) investigated the use of polyethersulfone (PES)/magnesium silicate (MS) membranes in the removal of free fatty acids (FFA) in biodiesel. A practical adsorbent material should have a high capacity to contain the contaminant and high surface area for fast adsorption. Magnesium silicate (MS) has been developed for the purpose of non-aqueous adsorbent and has surface area and pore volume greater than PES cast film. By electrospinning a blend of PES and MS, the resultant PES/MS nanofibrous membrane has a higher surface area and pore volume than MS. Pure MS probably has a lower surface area and pore volume compared to PES/MS electrospun membrane due to agglomeration. The PES/MS electrospun composite membrane showed the highest adsorption capacity of 670 mg g^-1 and the most efficient removal rate over 90% for FFA.

2. Wide variety of polymers and materials have been used to form nanofibers
   Electrospinning has been used to make nanofibers from all major classes of materials either directly or indirectly. Although the process is predominantly used to make polymeric nanofibers, ceramic and metal nanofibers have also been constructed indirectly through electrospinning of their precursor material.
   See Natural polymer electrospinning data
   
   
3. Ease of fiber functionalization
   This benefit relates to the variety of polymer that can possibly be used to electrospin nanofibers. Functionalization of electrospun nanofibers can be achieved through simple blending of polymer solution prior to spinning, post-spinning surface functionalization or using core-shell electrospinning setup. Electrospinning is generally tolerant of small changes in solution properties due to the presence of additives and still maintains similar nanofiber morphology. Scaffaro et al (2023) did a comparison of nanofibers blended with Carvacrol or Chlorhexidine produced by electrospinning (ES) or solution blow spinning (SBS). The addition of drugs to the solution did not have a significant impact on the electrospun nanofiber output. However, with SBS, the changes in solution properties resulted in beaded fibers and bundling of the fibers. This demonstrated the greater tolerance of electrospinning in the production of functionalized nanofibers through blending.

   SEM micrographs of PLA nanofibers membranes obtained by electrospinning (ES) or solution blow spinning (SBS) of ES-PLA, SBS-PLA, ES-PLA/CHX, SBS-PLA/CHX, ES-PLA/CHX/GNP, SBS-PLA/CHX/GNP (a-c,a'-c'), and relative averages diameters (d) [Scaffaro et al 2023].

   
   
4. Ease of material combination
   Low requirements for electrospinning meant that different materials can be easily mixed together for spinning into fibers.
   
   
5. Relatively low start up cost
   Simple electrospinning setup generally cost a few thousand dollars. For use in laboratory environment, a setup can be self-assembled from off-the-shelf components or purchase fully assembled.
   See Assembly of electrospinning setup for spinning of nonwoven fibrous membrane - Basic Setup
   
   
6. Low learning curve for basic electrospinning
   With the guidance from a mentor, an individual with basic knowledge of polymer and electrostatics will be able to understand the basic concept of electrospinning within a couple of weeks.
   See Electrospinning Overview
   
   
7. Ease of fiber deposition onto other substrates
   Deposition of electrospun fibers requires the collecting surface to have a lower static charge. Electrospun fibers have been routinely deposited on surfaces such as metal, glass, microfibrous mat and water.
   See Collector
   
   
8. Variety of nanofibrous structures have been constructed
   Advances in electrospinning setup and process have seen development of tubular nanofibrous structure, yarns and 3D blocks of nanofibers.
   See Electrospun Structures
   
   
9. Mass production capability demonstrated
   Several companies have used electrospinning concept to spin nanofibrous membranes at an industrial level. Electrospinning setups for mass production of nanofibers are also commercially available.
   See Electrospinning Mass Production Output
   
   
10. Commercial applications:
    Electrospinning has been used in the construction of several commercially available products. Below are some examples,
    • Air filtration membrane
    • Face mask
    • Water filtration membrane
    • Cell culture plates
    • Woundcare patch
    List of companies