1091595-09-3Relevant articles and documents
Hydrogels with Reversible Mechanics to Probe Dynamic Cell Microenvironments
Rosales, Adrianne M.,Vega, Sebastián L.,DelRio, Frank W.,Burdick, Jason A.,Anseth, Kristi S.
, p. 12132 - 12136 (2017)
The relationship between ECM mechanics and cell behavior is dynamic, as cells remodel and respond to changes in their local environment. Most in vitro substrates are static and supraphysiologically stiff; thus, platforms with dynamic and reversible mechanical changes are needed. Herein, we developed hyaluronic acid-based substrates capable of sequential photodegradation and photoinitiated crosslinking reactions to soften and then stiffen the hydrogels over a physiologically relevant range of moduli. Reversible mechanical signaling to adhered cells was demonstrated with human mesenchymal stem cells. In situ hydrogel softening (from ca. 14 to 3.5 kPa) led to a decrease in the cell area and nuclear localization of YAP/TAZ, and subsequent stiffening (from ca. 3.5 to 28 kPa) increased the cell area and nuclear localization of YAP/TAZ. Each photoreaction was cytocompatible and tunable, rendering this platform amenable to studies of dynamic mechanics on cell behavior across many cell types and contexts.
Photocontrol of biological activities of protein by means of a hydrogel
Murayama, Shuhel,Kato, Masaru
, p. 2186 - 2191 (2010)
Because proteins show high activity and are essential for biological function, proteins are important and useful biomolecules; however, it is hard to control activities whenever and wherever required. Although some photoactivated proteins have been reported to date, such proteins have required a protein-specific design and sitespecific chemical modification. We have recently developed a method to encapsulate proteins within hydrogels that can be photocleaved with ultraviolet (UV) light, thus releasing the proteins; we refer to this method as protein activation and release from cage by external light (PARCEL). Biological activities of protein restricted by hydrogel encapsulation were recovered by applying external light to the protein-hydrogel. We also used these hydrogels to screen selective ligands as therapeutic agents for disease. This innovative technique for basic research in biology and biochemistry might also be useful in practical or clinical applications, such as biosensing, catalysis, and drug delivery.
Synthesis of photodegradable macromers for conjugation and release of bioactive molecules
Griffin, Donald R.,Schlosser, Jessica L.,Lam, Sandra F.,Nguyen, Thi H.,Maynard, Heather D.,Kasko, Andrea M.
, p. 1199 - 1207 (2013/05/22)
Hydrogel scaffolds are used in biomedicine to study cell differentiation and tissue evolution, where it is critical to control the delivery of chemical cues both spatially and temporally. While large molecules can be physically entrapped in a hydrogel, moderate molecular weight therapeutics must be tethered to the hydrogel network through a labile linkage to allow controlled release. We synthesized and characterized a library of polymerizable ortho-nitrobenzyl (o-NB) macromers with different functionalities at the benzylic position (alcohol, amine, BOC-amine, halide, acrylate, carboxylic acid, activated disulfide, N-hydroxysuccinyl ester, biotin). This library of polymerizable macromers containing o-NB groups should allow direct conjugation of nearly any type of therapeutic agent and its subsequent controlled photorelease from a hydrogel network. As proof-of-concept, we incorporated the N-hydroxysuccinyl ester macromer into hydrogels and then reacted phenylalanine with the NHS ester. Upon exposure to light (λ = 365 nm; 10 mW/cm2, 10 min), 81.3% of the phenylalanine was released from the gel. Utilizing the photodegradable macromer incorporating an activated disulfide, we conjugated a cell-adhesive peptide (GCGYGRGDSPG), a protein that exhibits enzymatic activity (bovine serum albumin (BSA)), and a growth factor (transforming growth factor-β1 (TGF-β1)) into hydrogels, controlled their release with light (λ = 365 nm; 10 mW/cm2, 0-20 min), and verified the bioactivity of the photoreleased molecules. The photoreleasable peptide allows real-time control over cell adhesion. BSA maintains full enzymatic activity upon sequestration and release from the hydrogel. Photoreleased TGF-β1 is able to induce chondrogenic differentiation of human mesenchymal stem cells comparable to native TGF-β1. Through this approach, we have demonstrated that photodegradable tethers can be used to sequester peptides and proteins into hydrogel depots and release them in an externally controlled, predictable manner without compromising biological function.
Near infrared light triggered release of biomacromolecules from hydrogels loaded with upconversion nanoparticles
Yan, Bin,Boyer, John-Christopher,Habault, Damien,Branda, Neil R.,Zhao, Yue
, p. 16558 - 16561 (2013/01/15)
Using a photosensitive hybrid hydrogel loaded with upconversion nanoparticles (UCNPs), we show that continuous-wave near-infrared (NIR) light (980 nm) can be used to induce the gel-sol transition and release large, inactive biomacromolecules (protein and
