Water-Dependent Blending of Pectin Films: The Mechanics of Conjoined Biopolymers

Abstract

Biodegradable pectin polymers have been recommended for a variety of biomedical applications, ranging from the delivery of oral drugs to the repair of injured visceral organs. A promising approach to regulate pectin biostability is the blending of pectin films. To investigate the development of conjoined films, we examined the physical properties of high-methoxyl pectin polymer-polymer (homopolymer) interactions at the adhesive interface. Pectin polymers were tested in glass phase (10–13% w/w water content) and gel phase (38–41% w/w water content). The tensile strength of polymer-polymer adhesion was measured after variable development time and compressive force. Regardless of pretest parameters, the adhesive strength of two glass phase films was negligible. In contrast, adhesion testing of two gel phase films resulted in significant tensile adhesion strength (p < 0.01). Adhesion was also observed between glass phase and gel phase films—likely reflecting the diffusion of water from the gel phase to the glass phase films. In studies of the interaction between two gel phase films, the polymer-polymer adhesive strength increased linearly with increasing compressive force (range 10–80 N) (R2 = 0.956). In contrast, adhesive strength increased logarithmically with time (range 10–10,000 s) (R2 = 0.913); most of the adhesive strength was observed within minutes of contact. Fracture mechanics demonstrated that the adhesion of two gel phase films resulted in a conjoined film with distinctive physical properties including increased extensibility, decreased stiffness and a 30% increase in the work of cohesion relative to native polymers (p < 0.01). Scanning electron microscopy of the conjoined films demonstrated cross-grain adhesion at the interface between the adhesive homopolymers. These structural and functional data suggest that blended pectin films have emergent physical properties resulting from the cross-grain intermingling of interfacial pectin chains.

Biomechanics of a Plant-Derived Sealant for Corneal Injuries

“…The low-profile pectin film was previously shown to be translucent, flexible, fracture resistant, and bioabsorbable. 10 , 15 , 23 , 28 , 29 Here, we showed that the pectin film was also rapidly and strongly adherent to the corneal surface―effectively sealing corneal incisions. The strongly adherent pectin was also used for en face harvest of the corneal epithelium.…”

Biomaterial-Assisted Anastomotic Healing: Serosal Adhesion of Pectin Films

“…The pectin powder was dissolved at 25 °C by a controlled increase in water as previously described [ 37 ]. Briefly, the complete dissolution of the pectin was obtained using a high-shear 10,000 rpm rotor-stator mixer (L5M-A, Silverson, East Longmeadow, MA, USA).…”

Functional Adhesion of Pectin Biopolymers to the Lung Visceral Pleura

“…Sequential swelling, softening, and fluidization of the particles was followed by dissolution [ 29 ]. As described elsewhere [ 30 ], the complete dissolution of the pectin was produced using a high-shear 10,000 rpm rotor-stator mixer (L5M-A, Silverson, East Longmeadow, MA, USA). Reproducible viscosity was ensured using a digital tachometer and ammeter (DataLogger, Silverson).…”