Advances in Photoreactive Tissue Adhesives Derived from Natural Polymers

Abstract

To stop blood loss and accelerate wound healing, conventional wound closure techniques such as sutures and staples are currently used in the clinic. These tissue-piercing wound closure techniques have several disadvantages such as the potential for causing inflammation, infections, and scar formation. Surgical sealants and tissue adhesives can address some of the disadvantages of current sutures and staples. An ideal tissue adhesive will demonstrate strong interfacial adhesion and cohesive strength to wet tissue surfaces. Most reported studies rely on the liquid-to-solid transition of organic molecules by taking advantage of polymerization and crosslinking reactions for improving the cohesive strength of the adhesives. Crosslinking reactions triggered using light are commonly used for increasing tissue adhesive strength since the reactions can be controlled spatially and temporally, providing the on-demand curing of the adhesives with minimum misplacements. In this review, we describe the recent advances in the field of naturally derived tissue adhesives and sealants in which the adhesive and cohesive strengths are modulated using photochemical reactions.

Cooperative Multivalent Weak and Strong Interfacial Interactions Enhance the Adhesion of Mussel-Inspired Adhesives

“…First, a coumarin-functionalized diol monomer (C) was added in the MIPs at a constant feed ratio of 5 mol %. Coumarin undergoes [2 + 2] photocycloaddition upon exposure to light of wavelength, λ = 340 nm, providing chemically cross-linked elastomeric materials (Figure B). ,,, An aliphatic diol (A) with nonpolar hydrocarbons was added at a feed ratio of 65 mol % to obtain elastomers with low moduli (internal plasticizer) after the cross-linking reaction of coumarin units. This unit also lowers the glass-transition temperatures of the MIPs .…”

Natural polymer‐based adhesive hydrogel for biomedical applications

“…However, artificial catechol-based hydrogels are generally too simple considering their chemical composition and grade structure, resulting in poor mechanical strengths and bonding strengths [12,70,120,[129][130][131][132][133][134]. As mentioned before, catechol groups are easily occupied by metal ions on the nonmatrix and are oxidised to quinone groups; thus, the hydrogen bond interaction playing the key adhesion role is weakened [14][15][16][17][18][19][20][21][22][23][24][25][26]. However, mussel adhesion proteins can form strong adhesions in aqueous media.…”

“…Hydrogel is a hydrophilic polymeric network of three‐dimensional (3D) cross‐linked structures that retain a significant amount of water [1, 2]. The soft swollen polymer networks formed as a result of physical or chemical cross‐linking show hydrophobic effects [2], electrostatic interactions [2–5], hydrogen bond interactions [6, 7], covalent bonds [8–11], and metal coordination chemistry [12–34]. Hydrogels can be tailored to achieve various cross‐linking densities, mechanical properties, and porous structures through various cross‐linking mechanisms and functional groups.…”

Light-Activated Adhesion and Debonding of Underwater Pressure-Sensitive Adhesives

“…The use of stimuli-responsive polymers that undergo physicochemical transitions in response to external stimuli, such as light, ions, voltage, or temperature, can provide PSAs with strong adhesion and easier on-demand removal. − Among them, the use of photoresponsive materials has become a popular strategy to modulate the adhesive strengths . For example, photoinduced [2 + 2] cycloaddition of coumarin-containing polymers has been used as a strategy to tailor the modulus and peel strength of polymers. − The study by June et al shows that the photolytic degradation of o -nitrobenzyl-derived polymers results in the reduction of adhesive strength when exposed to light …”

“…11−18 Among them, the use of photoresponsive materials has become a popular strategy to modulate the adhesive strengths. 19 For example, photoinduced [ modulus and peel strength of polymers. 20−22 The study by June et al shows that the photolytic degradation of onitrobenzyl-derived polymers results in the reduction of adhesive strength when exposed to light.…”