The Relationships between the Working Fluids, Process Characteristics and Products from the Modified Coaxial Electrospinning of Zein

Abstract

The accurate prediction and manipulation of nanoscale product sizes is a major challenge in material processing. In this investigation, two process characteristics were explored during the modified coaxial electrospinning of zein, with the aim of understanding how this impacts the products formed. The characteristics studied were the spreading angle at the unstable region (θ) and the length of the straight fluid jet (L). An electrospinnable zein core solution was prepared and processed with a sheath comprising ethanolic solutions of LiCl. The width of the zein nanoribbons formed (W) was found to be more closely correlated with the spreading angle and straight fluid jet length than with the experimental parameters (the electrolyte concentrations and conductivity of the shell fluids). Linear equations W = 546.44L − 666.04 and W = 2255.3θ − 22.7 could be developed with correlation coefficients of Rwl2 = 0.9845 and Rwθ2 = 0.9924, respectively. These highly linear relationships reveal that the process characteristics can be very useful tools for both predicting the quality of the electrospun products, and manipulating their sizes for functional applications. This arises because any changes in the experimental parameters would have an influence on both the process characteristics and the solid products’ properties.

Long-Term Effect against Methicillin-Resistant Staphylococcus aureus of Emodin Released from Coaxial Electrospinning Nanofiber Membranes with a Biphasic Profile

“…The average diameters of nanofibers with and without emodin were 692 ± 93 nm and 732 ± 82 nm, respectively. While the diameters were significantly different (p < 0.05) by comparative analysis; the decreased diameters of nanofibers containing emodin are likely due to the increased conductivity of electrospinning solution with emodin, whose structure has three hydroxyls and two carbonyl groups possibly contributing to this effect, because the higher electrical conductivity leads to higher starching forces in the jet fluid, thus decreasing fiber diameters [39].…”

“…Due to the concrete relationship between the electrospinning parameters and the resultant nanofiber properties [38,39], in particular, the diameters of nanofibers have some decisive influence on drug release profiles [40], all electrospinning parameters were carefully studied for preparation of emodin-loaded nanofiber membrane with core-shell structure. Considering the evaporation rate of electrospinning solutions is an important factor for controlling the morphology and electrospinnability of nanofibers, and emodin is highly hydrophobic, we tried several different solvents to prepare core solution and shell solution, such as anhydrous alcohol, acetone, mixture of acetone and DMAC (1:1, v/v), and mixture of acetone and DMAC (2:1, v/v) to dissolve CA, anhydrous alcohol, 0.2% dimethyl sulfoxide in anhydrous alcohol, and mixture of acetone and DMAC (2:1, v/v) to dissolve PVP with emodin; however, only the mixture of acetone and DMAC (2:1, v/v) showed optimal effect based on the electrospinnability, the morphology, and diameter distribution of the nanofibers containing emodin, thus the mixture of acetone and DMAC (2:1, v/v) was selected as the solvent to prepare the electrospinning solutions.…”

A Novel Profiled Multi-Pin Electrospinning System for Nanofiber Production and Encapsulation of Nanoparticles into Nanofibers

“…The connected voltage is also one of the key elements in electrospinning 57,67 . A high applied voltage (>40 kV) is normally required to initiate the upward needleless electrospinning fiber production.…”

Electrospun Environment Remediation Nanofibers Using Unspinnable Liquids as the Sheath Fluids: A Review

“…In sharp contrast, the modified coaxial electrospinning can be exploited for producing core-shell structures, just as the traditional ones [30], but also can be utilized to prepare nanocoating on the core polymeric fibers [31]. What is more, when solvents are explored as the sheath working fluids, modified coaxial electrospinning can be utilized to stabilize the working process [32], keep the working processes from clogging, manipulate the nanofibers' diameter without the additions of salt or other additives, and systematically improve the nanofibers' quality. In the traditional blending electrospinning, the working process is regulated by a series of variables, including the properties of the solution, experimental parameters and surrounding conditions [33][34][35][36][37][38][39].…”