Polyion complex fiber and capsule formed by self‐assembly of poly‐L‐Lysine and gellan at solution interfaces

Abstract

Different characteristic surface structures such as capsules, regularly spaced droplets, and fibers are formed by electrostatic interaction between poly-L-lysine (PLL) and gellan gum via polyion complex (PIC) formation. Spherical droplet PIC capsules of varying diameters form in solutions. Some dyes adsorb on the surface of the capsules, and other dyes penetrate into the capsules. The strong PIC fiber can be spinnable by gravity and by wet spinning in ethanol. This fiber possesses a counterion pairing structure and exhibits the nervation/veining pattern and hollow yarn. The tensile strength of the fiber is 27.8 kg/mm 2 [1.40 g/denier (d)] and the knotting strength is 9.98 kg/mm 2 (1.13 g/d). By using an organic crosslinking agent, epichlorohydrin, the tensile strength can be increased to 38.5 kg/mm 2 (2.46 g/d) and the knotting strength can be increased to 12.2 kg/mm 2 (1.99 g/d). The PIC fiber can be dyed by five different dyeing procedures such as direct and vat dyeings. The PLL PIC fiber is water insoluble and has potential as a new synthetic polypeptide fiber technology.

Interfacial Polyelectrolyte Complex Spinning of Cellulose Nanofibrils for Advanced Bicomponent Fibers

“…This leads us to suggest, in accordance with most previous works, that at the interface of the two components forms a load-bearing strong skin that prevents diffusion of the polycation deep into the filament, resulting in a core-shell strucutre. 42,48,[57][58][59][60] The majority solid component was interpreted to be TOCN based on the color of the wet filament (see Figure 1c) when using dyed TOCN dispersion (blue) and polycation solution (pink, PDADMAC).…”

Polyelectrolyte complex materials from chitosan and gellan gum

“…The main aim of this study is to explore the formation of wound dressing through a simple polyelectrolyte complex using chitosan (CH) and gellan gum (GG). The mechanical properties, biocompatibility and antibacterial activity of free-standing CH and GG films are improved by incorporating titanium dioxide (TiO 2 ), silver (Ag) and zinc oxide (ZnO) nanoparticles [293][294][295][296][297] . Levofloxacin, an antibiotic is also included into CH films to improve the biopolymer's antibacterial properties.…”

“…The challenge faced in the formation of a CH-GG PEC-film is to prevent the formation of a precipitate in the form of fibers or a capsule 162,163,167,294 Films were prepared by evaporative casting, i.e. solutions or dispersions were deposited onto an acrylic plate and allowed to dry for 2 days under controlled conditions (21 °C, 60 ± 10% relative humidity, RH) (Figure 2.1).…”

“…In contrast, chitosan (CH) and gellan gum (GG) solutions are unable to be mixed together due to insoluble gellan gum in acidic medium. The mixing between CH and GG solutions results in the formation of a precipitate due to charge overcompensation at the interface in the form of fibres, capsules or coacervate structures depending on the complexation conditions 162,163,167,294 . There are no literature reports on the formation of CH-GG PEC-films.…”

Polyion Complex Fiber and Capsule Formed by Self-Assembly of Chitosan and Poly(α,L-glutamic acid) at Solution Interfaces

“…san and poly(a,l-lysine) (PLL) and anionic gellan and poly(a,l-glutamic acid) (PLG) can give characteristic structures, including capsule and fiber formation, at the interface in aqueous solutions. [15,16] Poly(a-amino acid) fibers have been expected as an animal-like fiber, which has various properties as those of silk, wool and the intermediates. [17 -19] Many kinds of organic solvent-soluble polypeptides were spun as fibers from the polypeptide solutions in dichloroacetic acid, benzene, and methylene dichloride during 1945-1970s.…”