Hydrogel Research Articles

Extraculuar material promoted C3H10T1/2 chondrogenic differentiation than Pellet cultured in vitro

Objective In order to understand the chondrogenesis differentiation of mesenchymal stem cells in either hydrogel or pellet culture, we applied the two methods and reveal the possible mechanism and for further investigation. Methods In C3H10T1/2 chondrogenic differentiation, we apply extracellular matrix hydrogel mixed the cell suspensions of freshly prepared (including scaling chondroitin sulfate, sodium hyaluronate synthesis and cross-linking agent) co-culture system and high cell density pellet formed by centrifugation. Chondrogenic differentiation of C3H10T1/2 was induced by treatment with TGF-β3 (10 ng/ml), dexamethasone (100 nmol/L), ascorbic acid (50 ug/ml), 1∶100 dilution ITS+Premix and high glucose-DMEM medium with 0.2 volume fraction fetal bovine serum. And high glucose-DMEM medium with 0.2 volume fraction fetal bovine serum is for control group. Histochemistry staining was utilized to identify extracellular proteoglycan and real-time PCR was performed to assess gene expression of SOX9, collagen IIa1/Xa1 and aggrecan for the 1st, 2nd and 3rd week respectively. Results In the hydrogel model for 3 weeks chondrogenic differentiation, the expression of master transcription factor SOX9 was upregulated in both culture models. While the marker genes of collagen IIa1 and collagen Xa1 were all promoted in hydrogel culture, the aggrecan gene expression was peaked in pellet culture. In addition, immunocytochemistry analysis of the hydrogel and pellet for 3 week illustrated the expression of extracellular matrix and more obviously in the hydrogel model. Conclusion In compared with pellet culture, the MSCs in the hydrogel were more likely promoted chondrogenesis leading to the eventual expression of marker genes. And the hydrogel would be applied in regeneration of cartilage injury. Key words: Mesenchymal stem cells; Cellular microenvironment; Chondrocytes

Hydrogel-Nanoparticles Composite System for Controlled Drug Delivery.

Biodegradable poly(ethylene glycol)-block-poly(-lactic acid) (PEG-b-PLA) nanoparticles (NPs) were prepared by nanoprecipitation with controlled dimension and with different electric charges, as monitored by dynamic light scattering (DLS). Then NPs were loaded within hydrogels (HG) developed for biomedical applications in the central nervous system, with different pore sizes (30 and 90 nm). The characteristics of the resulting composite hydrogel-NPs system were firstly studied in terms of ability to control the release of small steric hindrance drug mimetic. Then, diffusion-controlled release of different charged NPs from different entangled hydrogels was studied in vitro and correlated with NPs electric charges and hydrogel mean mesh size. These studies showed different trends, that depend on NPs superficial charge and HG mesh size. Release experiments and diffusion studies, then rationalized by mathematical modeling, allowed us to build different drug delivery devices that can satisfy different medical needs.

Self-healing and Swelling Kinetics of a New Polyacrylic Acid Hydrogels

Self-healing and Swelling Kinetics of a New Polyacrylic Acid Hydrogels

Construction of left atrial appendage three-dimensional model based on transesophageal echocardiography and its value in preoperative simulated left atrial appendage closure

Objective To evaluate the accuracy of simulated operation before the left atrial appendage (LAA) occlusion by filed LAA model with soft materials, which is based on transesophageal three-dimensional echocardiography (3D-TEE). Methods Silica and hydrogel were mixed to imitate cardiac tissue. Silica and hydrogel mixed materials, silica and Tangoplus were subjected to mechanical detection and ultrasonic shear wave elastography (SWE). The preoperative and postoperative 3D-TEE image processing was performed on 21 patients undergoing LAA occlusion. The silica and hydrogel LAA 3D model, silicone model and Tangoplus model were acquired to evaluate the accuracy of 3D model. LAA closure was simulated using the 3D models and the compression ratio of the device in models was compared with the value measured in operation. Results The silica and hydrogel mixed materials were successfully prepared. The elastic modulus and stress-strain curve were closer to the myocardial tissue. Twenty-one 3D printing models of three materials were obtained in 21 patients based on 3D-TEE images.There was no significant difference in the anchor zone between the 3D model and 3D-TEE (P>0.05). The 3D model measurements were consistent with the 3D-TEE measurements. The compression ratios of the decive in the 3D models of all three materials were greater than those measured in operation, and the compression ratio of the device in the 3D model of silica and hydrogel materials had a better correlation with that measured in operation (r=0.900, P<0.01). Conclusions The 3D model of LAA made of silica and hydrogel material based on 3D-TEE can improve the accuracy of the LAA occlusion simulation, also can optimize the preparation of LAA occlusion. Key words: Echocardiography, transesophageal, three-dimensional; Three-dimensional printing; Left atrial appendage; Soft printing material

Keep still! Immobilizing animals with hydrogels

Keep still! Immobilizing animals with hydrogels

Research progress in hydrogel in radiotherapy of localized prostate cancer

In recent years, the incidence rate of prostate cancer has been gradually elevated year by year in China. External radiotherapy yields similar clinical efficacy to surgery in the treatment of localized prostate cancer. Because the rectum is close to the prostate, the radiotherapy targeting for prostate cancer constantly causes radiation-related proctitis. Recently, multiple researchers have attempted to inject polyethylene glycol hydrogel into the rectal prostate space to separate the rectum from the prostate, thereby reducing the radiation dose coverage for the rectum and minimizing the risk of radiation-related proctitis. In this article, the application basis, radiation stability, injection technology, dosimetry and clinical efficacy of polyethylene glycol hydrogel injection were summarized. Key words: Prostate neoplasms/radiotherapy; Polyethylene glycol hydrogel; Radiation proctitis

Use of super absorbent hydrogels derivative from acrylamide with itaconic acid and itaconates to remove metal ions from aqueous solutions

ABSTRACTPoly(acrylamide‐co‐itaconic acid) (AAm/IA) and poly(acrylamide‐co‐monomethoxyethyl itaconate) (AAm/MEI) hydrogels (HGs) synthesized at different molar ratios were used to study the adsorption of some metal ions as Cu2+, Ni2+, Pb2+, Cd2+, and Fe3+ in aqueous solutions at different concentration: 10, 50, 100, 500, and 1000 mg L−1. Statistical analysis was performed and the effect of the metal ion, ion concentration, and hydrogel (HG) composition, on adsorption and adsorption efficiency, was evaluated for both HGs studied (AAm/IA and AAm/MEI) and each factor gave rise to significant differences (P ≤ 0.05). The adsorption depends on the type of ion, its concentration, and also influenced by the type and composition of the HGs. For each system the adsorption efficiencies for all ions were similar with exception of Fe3+, which showed the highest adsorption efficiency in AAm/MEI HG, but the less for the AAm/IA. For both systems, the maximum adsorption efficiency was observed when the molar ratio AAm/IA or AAm/MEI is 80/20. When the adsorption was carried out with individual ions, AAm/MEI HG was more efficient than AAm/IA. For a multielement sample of Cu2+, Ni2+, Pb2+, and Cd2+, both HGs could adsorb all the ions and their behavioral trend was the same in both cases, in which the adsorption efficiency was Pb2+ &gt; Cu2+ &gt; Cd2+ &gt; Ni2+. The results of the statistical analysis evidence the advantage of its use in this type of studies. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 46999

Effect of hyaluronic acid-gelatin double-network hydrogel on osteogenic differentiation of rat bone marrow mesenchymal stem cells

Effect of hyaluronic acid-gelatin double-network hydrogel on osteogenic differentiation of rat bone marrow mesenchymal stem cells

Interaction of blockers on drilling fluids rheology and its effects on sealing of fractures and prevention of filtrate invasion

Drilling fluids from oil wells play an important role in the drilling operations, including cleaning and maintaining well stability, as well as cooling and lubricating the drill bit. Invasion of fluid in the rock formation, through natural or induced fractures, can compromise the entire well. In this work we evaluated the effect of combination of viscosifiers xanthan gum (XG), carboxymethylcellulose (CMC), Hydroxypropylstarch (HPS) and bentonite in the interaction with lost circulation materials diatomaceous earth (DE) and hydrogel (HG). The main objective was to obtain a product with adequate rheological properties showing viscoelastic behavior and minimizing loss of fluid to the wellbore. Tests of X-ray diffraction (XRD) and zeta potential were performed to analyze the interactions between the particles present in the fluids. With rheological tests we studied the effects of the addition of different components on the fluid rheology. XRD technique showed that the bentonite deflocculated only in polymer suspensions with DE. The results of zeta potential suggest that only the fluid with Hydroxypropylstarch and HG was completely flocculated and unstable, showed through particle sizes distribution tests. The gel modulus (G′) and viscous modulus (G″) of the fluids were affected by the interaction of bentonite layers with lost circulation materials particles, with significant increase of G′ with the addition of HG to the suspension. There was a decrease of viscosity due to agglomeration of HG and DE particles, an increase of G’ can be observed as well. Among all the fluids, the suspension of CMC and bentonite showed better affinity with the HG lost circulation material, presenting thermal stability and a wide range of particle size, essential property to avoid the loss of fluid through the fractures and pores of the rock formation.

Influence of Graphene Oxide on the Rheological Properties of Poly(vinyl alcohol)/Borate Hydrogel

Influence of Graphene Oxide on the Rheological Properties of Poly(vinyl alcohol)/Borate Hydrogel

Effect of a novel hydrogel amendment and seedling plugs volume on the quality of ornamental/miniature tomato

The market for ornamental/miniature plants values aesthetic morphological characteristics, which give harmony to the potted plant. These traits depend on the growing media capacity to maintain quality and plant longevity. The use of hydrogels has increased recently in order to achieve visually attractive and long-lasting plants. Thus, this study aimed to evaluate the effects of a novel hydrogel (H) amendment and seedling plugs volume (SPV) on the quality of ornamental/miniature tomato. Seedlings of tomato cv. BRS Finestra were produced in 200 and 162 plugs plastic trays - with 18 cm³ trapezium-shaped plugs and 50 cm³ conically shaped plugs, respectively. 18 cm³ plugs and H amendment presented several significant responses for plant characters - height, soluble solids, number of leaves, stem diameter, shoot dry matter and fruits weight per plant; making evident the advantages of using a growing medium of smaller volume and this copolymer amendement. Although consistent results were obtained, a combination of both these factors in terms of an optimal aesthetic value and considering all the morphological traits could not be accomplished. Therefore it’s necessary to study other elements such as plant nutrition and the use of plant growth regulators to complement them, aiming to promote better quality.

Cathelicidin Related Antimicrobial Peptide (CRAMP) Enhances Bone Marrow Cell Retention and Attenuates Cardiac Dysfunction in a Mouse Model of Myocardial Infarction.

Acute myocardial infarction (MI) and the ensuing ischemic heart disease are approaching epidemic state. Unfortunately, no definitive therapies are available and human regenerative therapies have conflicting results. Limited stem cell retention following intracoronary administration has reduced the clinical efficacy of this novel therapy. Cathelicidin related antimicrobial peptides (CRAMPs) enhance chemotactic responsiveness of BMSPCs to low SDF-1 gradients, suggesting a potential role in BMSPCs engraftment. Here, we assessed the therapeutic efficacy of CRAMPs in the context of BMSPCs recruitment and retention via intracardiac delivery of CRAMP-treated BMSPCs or CRAMP-releasing hydrogels (HG) post-AMI. For cell transplantation experiments, mice were randomized into 3 groups: MI followed by injection of PBS, BMMNCs alone, and BMMNCs pre-incubated with CRAMP. During the in vivo HG studies, BM GFP chimera mice were randomized into 4 groups: MI followed by injection of HG alone, HG + SDF-1, HG + CRAMP, HG + SDF-1 + CRAMP. Changes in cardiac function at 5weeks after MI were assessed using echocardiography. Angiogenesis was assessed using isolectin staining for capillary density. Mice treated with BMMNCs pre-incubated with CRAMP had smaller scars, enhanced cardiac recovery and less adverse remodeling. Histologically, this group had higher capillary density. Similarly, sustained CRAMP release from hydrogels enhanced the therapeutic effect of SDF-1, leading to enhanced functional recovery, smaller scar size and higher capillary density. Cathelicidins enhance BMMNC retention and recruitment after intramyocardial administration post-AMI resulting in improvements in heart physiology and recovery. Therapies employing these strategies may represent an attractive method for improving outcomes of regenerative therapies in human studies.

A Review On- Hydrogel

A Review On- Hydrogel

Swelling Degree and Diffusion Parameters of Poly (Sodium Acrylate-Co-Acrylamide) Hydrogel for Removal of Water Content From Biodiesel

Hydrogels particles swell in the presence of an adequate solvent and soak the solvent into the cross-linked matrix of the particle, therefore they have great potential to remove soluble and insoluble water from liquid fuels, such as biodiesel, diesel and blends. In this paper, kinetic parameters and hydrophilic properties of polyacrylamide and poly(sodium acrylate-co-acrylamide) (AAm-co-SA) hydrogels were investigated to provide data for future equipment designs and devices that use these materials in removing water from Biodiesel. New hydrogels synthesized with sodium acrylate and acrylamide obtained a swelling ratio (weight of the swollen sample to that of the dry sample) of W8=108.8 g water/g hydrogel, much higher than hydrogels developed in previous research (W8=14.36 g/g) to remove water from biodiesel. Preliminary tests with the new hydrogel developed showed its ability to reduce water content from biodiesel.

Preparation and Application of γ-Polyglutamic Acid Hydrogel

Preparation and Application of γ-Polyglutamic Acid Hydrogel

Study on Physicochemical Properties and Biocompatibility of Injectable Chitosan-hyaluronic Acid Hydrogel Loaded with NGF

Study on Physicochemical Properties and Biocompatibility of Injectable Chitosan-hyaluronic Acid Hydrogel Loaded with NGF

Paracrine of human adipose-derived mesenchymal stem cells in three-dimensional culture containing functionized self assembling peptide nanofiber hydrogel

Objective To study the paracrine of human adipose-derived mesenchymal stem cells (ADMSCs) in three-dimensional culture containing functionized self assembling peptide nanofiber hydrogel and the influencing factors. Methods ADMSCs were isolated and extracted. Three kinds of peptides (RADAI-16, RGD, KLT) were prepared and functionized self assembling peptide nanofiber hydrogel was made by mixing RADAI-16, RGD and KLT with a volume ratio of 2∶1∶1. Under AFM, the morphology of RADAI-16, RGD, KLT and functionized self assembling peptide nanofiber hydrogel was observed (n=4). ADMSCs were cultured under the three-dimensional condition containing peptide nanofiber hydrogel. ADMSCs were subjected to in situ three-dimensional cultivation for 1 day, then the concentrations of hepatocyte growth factor (HGF, n=3) and vascular endothelial growth factor (VEGF, n=3) were determined in the supernatatn by enzyme linked immunosorbent assay (ELISA). The cells were extracted in peptide nanofiber hydrogel and the expression of heme oxygenase-1 (HO-1, n=3) was detected by Western blotting. The cultured ADMSCs in hypoxic condition and normal circumstance served as controls. Results ADMSCs showed long spindle shape and grew in a whirlpool shape. The diameter of RADAI-16, RGD, KLT and functionized self assembling peptide nanofiber hydrogel was (17.34±1.82), (15.50±1.41), (13.77±1.18) and (20.26±1.25) nm, respectively. The concentration of HGF under three conditions was (47.31±6.75), (247.86±17.59), and (297.25±17.95) ng/L, respectively, and that of VEGF was (218.30±3.03), (267.13±4.27) and (289.14±3.11) ng/L, respectively. Both HGF and VEGF were paracrined more in condition of functionized self assembling peptide nanofiber hydrogel (P=0.000). Western blotting results showed that the expression of HO-1 in the three-dimensional culture group was about 2 times (P=0.000) higher than that in the ordinary culture group, and was 1.2 times higher than that in the hypoxia culture group (P=0.033). Conclusion The three-dimensional culture mediated by the functionized self assembling peptide nanofiber hydrogel can promote the paracrine of ADMSCs, such as HGF and VEGF, and hypoxia is one of the important elements. Key words: Adipose derived Mesenchymal stem cells; Three-dimensional culture; Functionized self assembling peptide nanofiber hydrogel; Paracrine; Hypoxia

Growth, Characterization and Conductivity of Chromium Mixed Cadmium Oxalate Crystals

AbstractChromium mixed cadmium oxalate (CMCO) [Cr:Cd (C2O4).3H2O] crystals are grown by gel diffusion method using silica hydro gel as growth media at ambient temperature. The optimum condition for growth is established by varying the parameters such as specific gravity, pH, gel aging, concentration of reactants and ratio of mixture to . Energy dispersive X‐ray spectroscopy (EDX) confirms the existence of and ions in the crystal lattice of CMCO. Thermo‐gravimetric analysis (TGA) reveal that, the CMCO are thermally stable up to 950 °C, which confirms the presence of three water molecules in the crystal lattice of CMCO. FT‐IR spectrum exhibits the presence of OH, carboxyl group and metal‐oxygen bonding. In this study, the occupation of vacancies of ions by cations in the lattice of mixed cadmium oxalate crystals without altering the morphology of the parent crystal is confirmed.

Rapid prototyping of hydrogel structures-scaffolds for artificial organs

Rapid prototyping of hydrogel structures-scaffolds for artificial organs

Synthetic extracellular matrix mimic hydrogel improves efficacy of mesenchymal stromal cell therapy for ischemic cardiomyopathy

BackgroundMesenchymal stromal cells (MSC) repair infarcted hearts mainly through paracrine mechanisms. Low cell engraftment limits the release of soluble paracrine factors (SF) over time and, consequently, MSC efficacy. We tested whether a synthetic extracellular matrix mimic, a hydrogel containing heparin (H-HG), could ameliorate MSC engraftment and binding/release of SF, thus improving MSC therapy efficacy. Methods and resultsIn vitro, rat bone-marrow MSC (rBM-MSC) were seeded and grown into H-HG. Under normoxia, the hydrogel did not affect cell survival (rBM-MSC survival >90% at each time point tested); vice versa, under hypoxia the biomaterial resulted to be protective for the cells (p < .001 vs rBM-MSC alone).H-HG or control PEG hydrogels (HG) were incubated with VEGF or bFGF for binding/release quantification. Data showed significantly higher amount of VEGF and bFGF bound by H-HG compared with HG (p < .05) and a constant release over time.In vivo, myocardial infarction (MI) was induced in female Sprague Dawley rats by permanent coronary ligation. One week later, saline, rBM-MSC, H-HG or rBM-MSC/H-HG were injected in the infarct zone. The co-injection of rBM-MSC/H-HG into infarcted hearts significantly increased cardiac function. Importantly, we observed a significant gain in MSC engraftment, reduction of ventricular remodeling and stimulation of neo-vasculogenesis. We also documented higher amounts of several pro-angiogenic factors in hearts treated with rBM-MSC/H-HG. ConclusionsOur data show that H-HG increases MSC engraftment, efficiently fine tunes the paracrine MSC actions and improves cardiac function in infarcted rat hearts. Statement of SignificanceTransplantation of MSC is a promising treatment for ischemic heart disease, but low cell engraftment has so far limited its efficacy. The enzymatically degradable H-HG that we developed is able to increase MSC retention/engraftment and, at the same time, to fine-tune the paracrine effects mediated by the cells. Most importantly, the co-transplantation of MSC and H-HG in a rat model of ischemic cardiomyopathy improved heart function through a significant reduction in ventricular remodeling/scarring and amelioration in neo-vasculogenesis/endogenous cardiac regeneration. These beneficial effects are comparable to those obtained by others using a much greater number of cells, strengthening the efficacy of the biomaterial used in increasing the therapeutic effects of MSC. Given its efficacy and safety, documented by the absence of immunoreaction, our strategy appears readily translatable to clinical scenarios.