Boronate ester cross-linked PVA hydrogels for the capture and H2O2-mediated release of active fluorophores.
Ontology highlight
ABSTRACT:
SUBMITTER: Williams GT
PROVIDER: S-EPMC7497407 | biostudies-literature | 2020 May
REPOSITORIES: biostudies-literature
Publications
Boronate ester cross-linked PVA hydrogels for the capture and H<sub>2</sub>O<sub>2</sub>-mediated release of active fluorophores.
Williams George T GT Sedgwick Adam C AC Sen Sajal S Gwynne Lauren L Gardiner Jordan E JE Brewster James T JT Hiscock Jennifer R JR James Tony D TD Jenkins A Toby A ATA Sessler Jonathan L JL
Chemical communications (Cambridge, England) 20200501 41
A new set of PVA hydrogels were formed using the boronate ester fluorescent probe PF1 and the novel boronate fluorescent probe PT1 as the covalent crosslinkers. Treatment with aqueous H2O2 allowed triggered release of the fluorescent dye accompanied by complete dissolution of the hydrogel. ...[more]
Similar Datasets
Project description:Cells are capable of sensing the differences in elastic and viscous properties (i.e., the 'viscoelasticity') of their tissue microenvironment and responding accordingly by changing their transcriptional activity and modifying their behaviors. When designing viscoelastic materials to mimic the mechanical properties of native tissue niches, it is important to consider the timescales over which cells probe their microenvironment, as the response of a viscoelastic material to an imposed stress or strain is timescale dependent. Although the timescale of cellular mechano-sensing is currently unknown, hydrogel substrates with tunable viscoelastic spectra can allow one to probe the cellular response to timescale dependent mechanical properties. Here, we report on a cytocompatible and viscoelastic hydrogel culture system with reversible boronate ester cross-links, formed from pendant boronic acid and vicinal diol moieties, where the equilibrium kinetics of esterification were leveraged to tune the viscoelastic spectrum. We found that viscoelasticity increased as a function of the boronic acid and vicinal diol concentration, and also increased with decreasing cross-linker concentration, where the maximal loss tangent achieved with this system was 0.55 at 0.1 rad s-1. Additionally, we found that the cis-vicinal diols configuration altered the viscoelastic spectra, where a tan δ peak occurred at ~1 rad s-1 for hydrogels functionalized with boronic acid, while an additional peak formed at ≥10 rad s-1 for hydrogels functionalized with both boronic acid and cis-vic-diols. In experiments with NIH-3T3 fibroblasts cultured on these hydrogels, the projected cell area and nuclear area, focal adhesion tension, and subcellular localization of YAP/TAZ were all found to be lower for cells cultured on the viscoelastic hydrogels compared to elastic hydrogels with a similar storage modulus. Despite these differences, there was not a statistically significant relationship between the frequency dependent viscoelastic material properties characterized in this study and cellular morphologies, focal adhesion tension, or the subcellular localization of YAP. While these results demonstrate that mechanotransduction pathways are affected by viscoelasticity, they also suggest that these mechanotransduction pathways are not particularly sensitive to the frequency dependent viscoelastic material properties from 0.1 to 10 rad s-1.
| S-EPMC6764851 | biostudies-literature
Project description:The reversible condensation of catechols and boronic acids to boronate esters is a paradigm reaction in dynamic covalent chemistry. However, facile backward hydrolysis is detrimental for stability and has so far prevented applications for boronate-based materials. Here, we introduce cubic boronate ester cages 6 derived from hexahydroxy tribenzotriquinacenes and phenylene diboronic acids with ortho-t-butyl substituents. Due to steric shielding, dynamic exchange at the Lewis acidic boron sites is feasible only under acid or base catalysis but fully prevented at neutral conditions. For the first time, boronate ester cages 6 tolerate substantial amounts of water or alcohols both in solution and solid state. The unprecedented applicability of these materials under ambient and aqueous conditions is showcased by efficient encapsulation and on-demand release of β-carotene dyes and heterogeneous water oxidation catalysis after the encapsulation of ruthenium catalysts.
| S-EPMC10910528 | biostudies-literature
Project description:Cells may be captured and released using a photodegradable hydrogel (photogel) functionalized with antibodies. Photogel substrates were used to first isolate human CD4 or CD8 T-cells from a heterogeneous cell suspension and then to release desired cells or groups of cells by UV-induced photodegradation. Flow cytometry analysis of the retrieved cells revealed approximately 95% purity of CD4 and CD8 T-cells, suggesting that this substrate had excellent specificity. To demonstrate the possibility of sorting cells according to their function, photogel substrates that were functionalized with anti-CD4 and anti-TNF-? antibodies were prepared. Single cells captured and stimulated on such substrates were identified by the fluorescence "halo" after immunofluorescent staining and could be retrieved by site-specific exposure to UV light through a microscope objective. Overall, it was demonstrated that functional photodegradable hydrogels enable the capture, analysis, and sorting of live cells.
| S-EPMC4380505 | biostudies-other
Project description:Many molecules that could manipulate cellular function are not practical due to their large size and concomitant undesirable pharmocokinetic properties. Here, we describe a bioorthogonal, highly stable boronate ester (HiSBE) synthesis and use this reaction to synthesize a biologically active molecule from smaller precursors in a physiological context. The rapid rate of HiSBE synthesis suggests that it may be useful for assembling a wide variety of biologically active molecules in physiological solutions.
| S-EPMC3149976 | biostudies-literature
Project description:We have developed a photoresponsive DNA-cross-linked hydrogel that can be photoregulated by two wavelengths with a reversible sol-gel conversion. This photoinduced conversion can be further utilized for precisely controllable encapsulation and release of multiple loads. Specifically, photosensitive azobenzene moieties are incorporated into DNA strands as cross-linkers, such that their hybridization to complementary DNAs (cDNAs) responds differently to different wavelengths of light. On the basis of the rheology variation of hydrogels, it is possible to utilize this material for storing and releasing molecules and nanoparticles. To prove the concept, three different materials--fluorescein, horseradish peroxidase, and gold nanoparticles--were encapsulated inside the gel at 450 nm and then released by photons at 350 nm. Further experiments were carried out to deliver the chemotherapy drug doxorubicin in a similar manner in vitro. Our results show a net release rate of 65% within 10 min, and the released drug maintained its therapeutic effect. This hydrogel system provides a promising platform for drug delivery in targeted therapy and in biotechnological applications.
| S-EPMC3075801 | biostudies-literature
Project description:The incorporation of double dynamic bonds into hydrogels provides an effective strategy to engineer their performance on demand. Herein, novel hydrogels were PREPARED by combining two kinetically distinct dynamic covalent bonds, boronate ester and acylhydrazone bonds, and the synergistic properties of the hydrogels were studied comprehensively. The functional diblock copolymers P(N-isopropyl acrylamide-co-N-acryloyl-3-aminophenylboronic acid)-b-(N-isopropyl acrylamide-co-diacetone acrylamide) (PAD) were prepared via reversible addition-fragmentation chain transfer (RAFT) polymerization. The hydrogel was constructed by exploiting dynamic reaction of phenyboronic acid moieties with polyvinyl alcohol (PVA) and ketone moieties with adipic dihydrazide (ADH) without any catalyst. The active boronate ester linkage endows the hydrogel with fast gelation kinetics and self-healing ability, and the stable acylhydrazone linkage can enhance the mechanical property of the hydrogel. The difference in kinetics endows that the contribution of each linkage to mechanical strength of the hydrogel can be accurately estimated. Moreover, the mechanical property of the hydrogel can be readily engineered by changing the composition and solid content, as well as by controlling the formation or dissociation of the dynamic linkages. Thus, we provide a promising strategy to design and prepare multi-responsive hydrogels with tunable properties.
| S-EPMC7077654 | biostudies-literature
Project description:Here we report the synthesis and characterization of pH-responsive, self-healing hydrogels based on boronate-catechol complexation.
| S-EPMC4526106 | biostudies-literature
Project description:Hydrogels with tunable viscoelasticity hold promise as materials that can recapitulate many dynamic mechanical properties found in native tissues. Here, covalent adaptable boronate bonds are exploited to prepare hydrogels that exhibit fast relaxation, with relaxation time constants on the order of seconds or less, but are stable for long-term cell culture and are cytocompatible for 3D cell encapsulation. Using human mesenchymal stem cells (hMSC) as a model, the fast relaxation matrix mechanics are found to promote cell-matrix interactions, leading to spreading and an increase in nuclear volume, and induce yes-associated protein/PDZ binding domain nuclear localization at longer times. All of these effects are exclusively based on the hMSCs' ability to physically remodel their surrounding microenvironment. Given the increasingly recognized importance of viscoelasticity in controlling cell function and fate, it is expected that the synthetic strategies and material platform presented should provide a useful system to study mechanotransduction on and within viscoelastic environments and explore many questions related to matrix biology.
| S-EPMC6145256 | biostudies-literature
Project description:A new class of temperature responsive polymer, termed PADO, is synthesized by reversible addition-fragmentation chain-transfer polymerization. Synthesized from copolymerization of diacetone acrylamide (DAAM), di(ethylene glycol) ethyl ether acrylate, and oligo(ethylene glycol) methyl ether acrylate, PADO polymer phase separates at temperature above its lower critical solution temperature (36-42 °C) due to enhanced hydrophobic interactions between the short ethylene glycol side chains. Solution of PADO polymers exhibit injectable shear-thinning properties and reach sol-gel transition rapidly (<5 min) at 37 °C. When the ketone moieties on DAAM are linked by adipic acid dihydrazdie, PADO polymers form crosslinked and injectable acylhydrazone hydrogels, which are hydrolytically degradable at a mild acidic environment owing to the pH sensitive acylhydrazone bonds. The pH-responsive degradation kinetics can be controlled by tuning polymer contents and ketone/hydrazide ratio. Importantly, the injectable PADO hydrogels are highly cytocompatible and can be easily formulated for pH-responsive sustained protein delivery.
| S-EPMC8977444 | biostudies-literature
Project description:Microfluidic adhesion-based cell separation systems are of interest in clinical and biological applications where small sample volumes must be processed efficiently and rapidly. While the ability to capture rare cells from complex suspensions such as blood using microfluidic systems has been demonstrated, few methods exist for rapid and nondestructive release of the bound cells. Such detachment is critical for applications in tissue engineering and cell-based therapeutics in contrast with diagnostics wherein immunohistochemical, proteomic, and genomic analyses can be carried out by simply lysing captured cells. This paper demonstrates how the incorporation of four-arm amine-terminated poly(ethylene glycol) (PEG) molecules along with antibodies within alginate hydrogels can enhance the ability of the hydrogels to capture endothelial progenitor cells (EPCs) from whole human blood. The hydrogel coatings are applied conformally onto pillar structures within microfluidic channels and their dissolution with a chelator allows for effective recovery of EPCs following capture.
| S-EPMC3086588 | biostudies-literature