Remotely Triggered Liquefaction of Hydrogel Materials

Abstract

Adaptable behavior such as triggered disintegration affords a broad scope and utility for (bio)materials in diverse applications in materials science and engineering. The impact of such materials continues to grow due to the increased importance of environmental considerations as well as the increased use of implants in medical practices. However, examples of such materials are still few. In this work, we engineer triggered liquefaction of hydrogel biomaterials in response to internal, localized heating, mediated by near-infrared light as external stimulus. This adaptable behavior is engineered into the readily available physical hydrogels based on poly(vinyl alcohol), using gold nanoparticles or an organic photothermal dye as heat generators. Upon laser light irradiation, engineered biomaterials underwent liquefaction within seconds. Pulsed laser light irradiation afforded controlled, on-demand release of the incorporated cargo, successful for small molecules as well as proteins (enzymes) in their biofunctional form.

Poly(vinyl alcohol) Hydrogels: The Old and New Functional Materials

“…Moreover, it can also remove anions and cations and organic pollutants in dye wastewater. Very meaningful research results including remote liquefaction (Figure 6(a)) [127], molecular ink [128], contact lens sensor [129], and so on [130][131][132][133] are also reported. As a biocompatible polymer, PVA-based hydrogels prepared with bimetallic ions as crosslinking agents have high water retention properties, excellent mechanical strength, and self-healing properties and have also been studied for artificial skin and wearable sensor devices (Figure 6(b)) [120,134].…”

A Review on Hydrogels with Photothermal Effect in Wound Healing and Bone Tissue Engineering

“…The change in temperature can control the gel-sol transformation of thermosensitive hydrogels and release active factors for enhanced therapy [ 35 ]. Pedersen et al reported that a polyvinyl alcohol/gold nanorod (AuNR) hydrogel was heated to <50 °C under NIR irradiation and liquefied in 15–20 s, and the pulsed release model cargo of fluorescein isothiocyanate controlled by NIR irradiation was realized successfully [ 36 ]. Under NIR irradiation, [poly( d , l -lactide)-poly(ethylene glycol)-poly( d , l -lactide)/black phosphorus (BP) hydrogel undergo a sol-gel transition at 46.5 °C after only 20 s [ 37 ].…”

Review on Computer-Aided Design and Manufacturing of Drug Delivery Scaffolds for Cell Guidance and Tissue Regeneration

“…Another approach in developing “smart’ multiresponsive hydrogels is via the incorporation of temperature-sensitive additives, such as liposomes or nanoparticles ( Lu and Ten Hagen, 2020 ; Palmese et al, 2020 ). Recently, Pedersen et al (2020) developed hydrogel biomaterials with triggered liquefaction in response to internal, localized heating, mediated by near-infrared light as external stimulus. This adaptable behavior was obtained by combining poly(vinyl alcohol) hydrogel with gold nanoparticles or an organic photothermal dye as heat generators.…”

“…This adaptable behavior was obtained by combining poly(vinyl alcohol) hydrogel with gold nanoparticles or an organic photothermal dye as heat generators. Upon laser light irradiation, composite hydrogel underwent liquefaction within seconds allowing the controlled, on-demand release of the incorporated cargo ( Pedersen et al, 2020 ).…”