Sponge Matrix Research Articles

Preparation of humic acid water‐retaining agent‐modified polyurethane sponge as a soilless culture material

AbstractBased on the structural characteristics of the polyfunctional groups of humic acid (HA), a HA water‐retaining agent (HAA) was prepared by the polymerization of an aqueous solution using potassium humate, acrylic acid, sodium carboxymethyl cellulose, and bentonite. HAA was obtained by the polymerization of an aqueous solution using an assembly ligand, and a polyurethane (PU) sponge was used as a carrier to mix HAA in the foaming process of the PU sponge to obtain the HAA‐modified PU (HAA‐PU) sponge matrix. The HAA‐PU sponge prepared with the HAA‐to‐PU mass ratio of 1:4 had the strongest foaming volume and water absorption. Fourier transform infrared spectrometry, scanning electron microscopy, and thermal stability analysis showed the successful preparation of the HAA‐PU sponge substrate, which allowed for the slow entry or storage of moisture and nutrients. The results of the pea seedling growth test on the HAA‐PU sponge and soil CK (control check) group showed that the emergence rate of the HAA‐PU group was>60%. It was not affected by the amount of watering and provided plants with long‐term water and nutrition. The chlorophyll, and vitamin C content of pea seedlings grown in the HAA‐PU sponge group were higher than the soil CK group.

Adipose-Derived Stem Cell-Incubated HA-Rich Sponge Matrix Implant Modulates Oxidative Stress to Enhance VEGF and TGF-β Secretions for Extracellular Matrix Reconstruction In Vivo.

This study demonstrated both adipose-derived stem cells (ASCs) in vitro and in vivo combined with three-dimensional (3D) porous sponge matrices on implant wound healing. Sponge matrices were created from hyaluronic acid (HA), collagen (Col), and gelatin (Gel), constructing two types: HA-L (low content) and HA-H (high content), to be cross-linked with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC). Fourier transform infrared spectroscopy method verified carboxyl groups of HA and amino groups of Col and Gel reacting between the raw materials and scaffolds to identify the successive cross-linking. The swelling ratios of two types of sponge matrices were analyzed by water absorption capabilities, and the results displayed both over 30-fold dry scaffold weight enhancements. In biodegradation tests, matrices were hydrolyzed over time by three cutaneous enzymes, hyaluronidase, lysozyme, and collagenase I. ASCs from rats were cultured within the HA-H scaffold, demonstrating higher antioxidative abilities and secretions on related genes and proteins compared to the other two groups. The ASC HA-H matrix promoted cell proliferation to stimulate capillary angiogenesis inducer secretions, including vascular endothelial growth factor (VEGF) and transforming growth factor-β (TGF-β). In vivo histological examinations showed ASCs from implanted HA-H implant transported into the subcutis, and rat skin cells also infiltrated into the original matrix zone to increase the extracellular matrix (ECM) reconstructions. Our experimental data revealed that the ASC HA-H sponge implant was effective in improving wound repair.

Endodontic Perforation Closure by Five Mineral Oxides Silicate-Based Cement with/without Collagen Sponge Matrix.

Endodontic perforations are common accidents that occasionally happen as a result of misuse or difficult anatomy of some teeth; it may lead to teeth loss unless a good management is provided. Bioceramic (silicate-based) cements like mineral trioxide aggregate have a big role in management of such accidents. This case report aimed to evaluate the ability of five mineral oxides cement “5MO” in sealing two root canal perforations (furcation and postdrill perforations) and inducing clinical and radiographic healing in the periodontal tissues with/without the use of collagen sponge matrix. A 58-year-old healthy female was referred to our dental office complaining of severe pain in the upper left premolars' region. Periapical radiographic examination revealed unsatisfactory root canal treatment of the teeth #24 and #25 with a furcation perforation and a postdrill perforation, respectively. Cone-beam computed tomography “CBCT” scans confirmed the findings of the periapical radiography and revealed the presence of radiolucent lesions surrounding the apex of both teeth #24 and #25. The treatment plan was a nonsurgical root canal retreatment by endodontic access through the full-ceramic crowns. After three years of follow-up, CBCT scans revealed a complete healing and bone formation on both premolars. This case report indicates the use of 5MO cement for endodontic perforations management.

Increasing the acetification rate of Acetobacter aceti adsorbed on luffa sponge using recycle of incremental oxygenated medium.

Speeding up the production of vinegar from rice wine by acetification, using a packed-bed bioreactor with a luffa sponge matrix (LSM) as adsorption carrier of acetic acid bacteria (AAB), and the effect of oxygenation of the recycled medium were investigated. The 0.06 L/min recycle of medium resulted in a high oxygen-transfer coefficient, while optimal dissolved oxygen (DO) of the medium maximized planktonic AAB cell growth with no contamination due to high acid in an external reservoir without LSM. The highest acetification rate (ETA) of 2.857 ± 0.1g/L/day was achieved with DO 3.5-4.5ppm at 35 ± 1°C. To increase ETA, the optimized oxygenated medium was externally supplied and recycled at the ratio of 0.1. Therefore, acetification was conducted in both the bioreactor and reservoir resulting in an increased ETA (6 ± 0.2g/L/day). This also aligned with the highest system AAB biomass (confirmed by scanning electron microscopy). Under the recycled oxygenated medium supply consistently high biotransformation yields (average 77.3%) were observed over nine sequential cycles. Meanwhile, an average ETA of 6.3 ± 0.2g/L/day was obtained. This method can have practical applications in improving the efficiency and speeding up small-scale vinegar production.

A muscle-like magnetorheological actuator based on bidisperse magnetic particles enhanced flexible alginate-gelatin sponges

A novel muscle-like magnetorheological actuator (MMRA) was composed of magnetic field generator and magnetostrictive component. Herein, the magnetostrictive component with high flexibility and elasticity was constructed by embedding micron carbonyl iron particles and Fe3O4 nanoparticles wrapped with MWCNTs into the alginate-gelatin (AL-GE) sponge matrix through a freeze-drying method for the first time. The structural characterization, rheological properties and actuation performance of MMRA with various magnetic AL-GE sponges were investigated. And they were significantly influenced by the mass ratio of AL-GE and the mass fraction of bidisperse magnetic particles (BMPs). The results showed that the relative MR effect and loss factor under 1 T of sample AL1-GE4-30 are 324.11% and 0.18, and its maximum deformation is 3.46 mm at 200 mT of magnetic flux density, exhibiting superior flexibility and enhanced magneto-induced performance compared with other magnetic AL-GE sponge matrix. In addition, a possible mechanism was proposed to explain the magneto-controllable performance for the MMRA. It was found that the actuation behaviors were attributed to the uniform distribution of BMPs in the homogenous network structure of sponge matrix.

Sugar-templated conductive polyurethane-polypyrrole sponges for wide-range force sensing

Porous conductive polyurethane (PU) sponges were prepared by combining a sugar-templated fabrication of porous polyurethane elastomer and the in-situ polymerization of pyrrole inside the sponges. The conductive sponges had a uniform porous structure similar to the sugar cube templates and a unique micro-wrinkled structure of polypyrrole (PPy). Moreover, the conductive sponges exhibited good mechanical properties and electrical conductivity by the combination of elastomeric PU and conductive PPy, which make the conductive PPy-PU sponges as good candidates for pressure and strain sensitive materials. It was shown that a single PPy-PU conductive sponge was not only sensitive to large forces, but also sensitive to the tiny deformation by small forces such as 0.1 N, thus realizing a wide-range detection of pressure forces from 0.1 N to 200 N. Furthermore, the detection range could be further enlarged to more than 800 N by assembling a sponge array. A PPy-PU sponge matrix was also designed and showed potential application in multi-site position detection. These sugar-templated conductive sponges may find application for sensors in human physiological movement and intelligent monitoring.

Electromechanical Decoupling by Porous Aerogel Conducting Polymer

In the field of biointerface electronics, electromechanical decoupling—electrical performance independent of mechanical deformation—can ensure reliability of measured signals, which is critical in stable electrode. Herein, Chen et al. report such a decoupled and stretchable conductive polymer foam.

Enrichment and Recovery of Cr(VI) from Aqueous Solution via a Monolithic Loofah Sponge Modified by Tannins and Arginine

In this study, a monolithic loofah sponge (LS) matrix, which was pretreated by hemicellulase and decorated by amino and guanidine, was successfully endowed with two functions: adsorption and recovery for Cr(VI). As an adsorbent, the modified LS (LS–TAA) has a high adsorption capacity (327.91 mg/g) for Cr(VI), and can be handily reused because of its integrity, good mechanical strength and convenient separation from aqueous solution. As a carrier, the residue of Cr-loaded LS–TAA was discovered to be pure Cr2O3 nanoparticles after calcination. The effect of hemicellulase pretreatment and influencing factors, adsorption kinetics, thermodynamics and isotherm adsorption models were investigated. The samples were characterized by various means including SEM, EDX, FT–IR, XRD, XPS and TEM. The results demonstrated that the LS–TAA should be viewed as a low-cost environment functional material with application potential to treat Cr-polluted wastewater.

Recyclable polyvinyl alcohol sponge containing flower-like layered double hydroxide microspheres for efficient removal of As(V) anions and anionic dyes from water.

Layered double hydroxides (LDHs) are very promising adsorbents for the removal of anionic pollutants from water. However, the low adsorption efficiency and recycling difficulty of conventional LDH powders are obstacles to practical applications. Herein, a novel Zn/Fe-LDH composite sponge was successfully fabricated using a simple in-situ hydrothermal method. Characterization studies revealed that the composite sponge contained flower-like Zn/Fe LDH microspheres uniformly dispersed throughout a poly vinyl alcohol (PVA) sponge matrix. The specific surface area of the Zn/Fe-LDH composite sponge was 42.5 m2 g-1, approximately 5 times higher than the pristine PVA sponge (8.9 m2 g-1). Adsorption experiments revealed that Zn/Fe-LDH composite sponge exhibited a much higher adsorption ability for As(V) anions and methyl orange (MO) compared with a Zn/Fe-LDH powder or the pristine PVA sponge. The maximum adsorption capacity for As(V) was found to be 85.7 mg g-1. Furthermore, the Zn/Fe-LDH composite sponge showed high thermal stability, good mechanical stability and easy recoverability, thereby allowing reuse. Results guide the development of improved, low cost water treatment materials.

Inflammation, angiogenesis and fibrogenesis are differentially modulated by distinct domains of the snake venom metalloproteinase jararhagin

Jararhagin, a metalloprotease from Bothrops jararaca snake venom, is a toxin containing the metalloproteinase, disintegrin-like and cysteine-rich domains; it causes acute inflammation and damage to vascular tissue. However, the actions of these domains on key components of chronic inflammation have not been determined. Our aim was to investigate the effects of jararhagin (Jar), jararhagin-C (Jar-C) and o-phenantrolin-treated jararhagin (Jar-Phe), on inflammatory response, blood vessel formation and extracellular matrix deposition in the murine sponge model. The polyether-polyurethane sponge matrix was implanted into Balb/c mice and injected daily with Jar (400 ng), Jar-Phe (400 ng), Jar-C (200 ng) or saline (control). Nine days after implantation, the sponge discs were removed and processed. In the Jar-treated implants, some of inflammatory markers (N-acetyl-β-d-glucosaminidase activity, CCL2 and TNF-α) and TGF-β1 levels were higher compared with the control group. In the Jar-C group, the inflammatory markers myeloperoxidase activity and CXCL1 were higher compared with the control. In this group, VEGF levels and collagen deposition were also higher. Jar-Phe treatment was able to inhibit the activity and/or production of MPO, CXCL1, CCL2 and TGF-β. The differential effects of these proteins in modulating the main components of fibrovascular tissue may be exploited in the management fibroproliferative diseases.

Superhydrophobic sponge under ventilation: A novel approach for corrosion inhibition

Superhydrophobicity has attracted wide interest for metal corrosion inhibition. However, the short sustainability in underwater environment is a major barrier that hinders its practical application. In this study, we used a superhydrophobic sponge as cushion to isolate metal from bulk water phase. The superhydrophobic sponge matrix drastically alleviates underwater immersion corrosion. Water vapour from bulk seawater can be transported outside by inletting dry air to maintain dry environment as long as the ventilation exists. Compared with bare steel and the steel covered with the sole superhydrophobic sponge, the ventilated superhydrophobic sponge matrix effectively facilitated corrosion inhibition environment for steel.

Comparison of "Dimensionality" of Cancer Cell Culture in Gelfoam® Histoculture and Matrigel.

Cell and tissue culture can be performed on different substrates such as on plastic, in Matrigel™, and on Gelfoam®, a sponge matrix. Each of these substrates consists of a very different surface, ranging from hard and inflexible, a gel, and a sponge-matrix, respectively. Folkman and Moscona found that cell shape was tightly coupled to proper gene expression. The flexibility of a substrate is important for cells to maintain their optimal shape. Human osteosarcoma cells, stably expressing a fusion protein of av integrin, and green fluorescent protein (GFP), grew as a simple monolayer without any structure formation on the surface of a plastic dish. When the osteosarcoma cells were cultured within Matrigel, the cancer cells formed colonies but no other structures. When the cancer cells were seeded on Gelfoam®, the cells formed 3-dimensional tissue-like structures. These results indicate that Gelfoam® histoculture, unlike Matrigel™ culture, is true 3-dimensional.

Influence of salmonid aquaculture activities on a rock-cliff epifaunal community in Jervis Inlet, British Columbia

Benthic video surveys were carried out at two marine finfish aquaculture and associated reference sites in Jervis Inlet (JI), British Columbia. Substrate composition, epifaunal diversity, mat-forming taxa (primary indicators: opportunistic polychaete complexes (OPCs) and sulfide-oxidizing bacteria) and waste pellets were quantitatively assessed. Hard-bottom substrates were dominated by rock wall, skeletal sponge matrix, graded bedrock, rock-veneer, and cobble. Aquaculture waste outputs (modelled depositional carbon fluxes and observations of waste feed/faecal pellets) were correlated with benthic organic enrichment indicators (OPC and sulfide-oxidizing bacteria). Sulfide-oxidizing bacteria varied in abundance up to a modelled depositional carbon flux of ~2gCm−2day−1 where it sustained 50% areal coverage. Glass sponges revealed an inverse relationship with aquaculture waste outputs and sulfide-oxidizing bacteria. Plumose anemones and shrimp showed a low frequency of occurrence at reference sites; however, they were abundant within the near-field zone of the aquaculture sites associated with a higher modelled carbon flux. Future research should focus on the response of various taxa to depositional gradients and their potential role as secondary indicators of aquaculture activities associated with rock-cliff communities.

Cellulose nanocrystal-reinforced keratin bioadsorbent for effective removal of dyes from aqueous solution

High-efficiency and recyclable three-dimensional bioadsorbents were prepared by incorporating cellulose nanocrystal (CNC) as reinforcements in keratin sponge matrix to remove dyes from aqueous solution. Adsorption performance of dyes by CNC-reinforced keratin bioadsorbent was improved significantly as a result of adding CNC as filler. Batch adsorption results showed that the adsorption capacities for Reactive Black 5 and Direct Red 80 by the bioadsorbent were 1201 and 1070mgg−1, respectively. The isotherms and kinetics for adsorption of both dyes on bioadsorbent followed the Langmuir isotherm model and pseudo-second order model, respectively. Desorption and regeneration experiments showed that the removal efficiencies of the bioadsorbent for both dyes could remain above 80% at the fifth recycling cycles. Moreover, the bioadsorbent possessed excellent packed-bed column operation performance. Those results suggested that the adsorbent could be considered as a high-performance and promising candidate for dye wastewater treatment.

Appropriate mechanical strength of carbon black-decorated loofah sponge as anode material in microbial fuel cells

A new composite anode material, possessing an appropriate mechanical strength, was fabricated by depositing carbon black on the loofah sponge matrix surface. Carbon black was oxidized in nitric acid (HNO3) and hydrogen peroxide (H2O2), respectively, to increase electrochemical properties before starting deposition. Microbial fuel cell (MFC) with the H2O2 treated carbon black anode achieved the maximum power density of 61.7 ± 0.6 W/m3, which was higher than one decorated with the HNO3 treated or untreated carbon black. Scanning electron microscopy (SEM) observation showed a compact bacterial attachment on the H2O2 treated carbon black surface. Results of electrochemical impedance spectroscopy (EIS) and Tafel plots indicated a fast electron transfer rate between the H2O2 pre-treatment of carbon black and electrochemically active bacteria (EAB). Therefore, the H2O2 treated carbon black-loofah sponge anode was promising for MFC application in terms of its superior performance, straightforward fabrication method and ultra-low cost.

Chitosan sponge matrices with β-cyclodextrin for berberine loadinging

AbstractBiocompatible polymer sponge materials based on biodegradable natural polymer chitosan, which can be loaded with clinician-selected drugs are still in the centre of interest for their wide use in clinical practice. This study shows possibilities of the technology which combines simple addition of β-cyclodextrin (β-CD), with dialdehyde starch (DAS) as a cross-linking agent of chitosan, to chitosan solutions for subsequent formation of sponge matrix. The advantage of such system is in avoiding chemical modifications and working only with natural substances. It is shown that, in matrix formation during lyophilisation, β-CD molecules tend to accumulate on the surface of the porous matrix structure. This was confirmed by a study of the known inclusion complex of β-CD and salicylic acid (SA) in heptane. The same study was applied to berberine (BER) which can also form an inclusion complex with β-CD in a water solution. Moreover, adsorption of drugs on the surface of the porous structure has to be also taken into account. This enables the production of sponge topical medical preparations useful for sustained release of BER.

Performance of Mesenchymal Cell-Scaffold Constructs in Human Oral Reconstructive Surgery: A Systematic Review

Background: Different sources of cultured cells combined with different scaffolds (allogenic, xenogeneic, alloplastic or composite materials) have been tested extensively in vitro and in preclinical animal studies, but there have been only a few clinical trials involving humans. Aim: This study reviewed all of the English language literature published between January 1990 and December 2015 to assess the histological performance of different mesenchymal cell-scaffold constructs used for bone regeneration in human oral reconstructive procedures. Methods: An electronic search of the MEDLINE and Cochrane Central Register of Controlled Trials databases complemented by manual searching was conducted to identify studies involving histological evaluation of mesenchymal cell-scaffold constructs in human oral surgical procedures. The methodological quality of randomized controlled clinical trials and controlled clinical trials was assessed using the Cochrane Collaboration tool for assessing the risk of bias. Heterogeneity was assessed using Review Manager software. Considering the heterogeneity, the data collected were reported by descriptive methods and a meta-analysis was applied only to the articles that reported the same outcome measures. The articles were classified and described based on the material scaffolds used. Results: The search identified 1030 titles and 287 abstracts. Full-text analysis was performed for 32 articles, revealing 14 studies that fulfilled the inclusion criteria. Three randomized controlled clinical trials were identified as potentially eligible for inclusion in a meta-analysis. The studies were grouped according to the scaffold materials used: bone allograft (three studies), polyglycolic-polylactic scaffold (four studies), collagen sponge (two studies), and bovine bone matrix (five studies). The stem cells used in these studies had been sourced from the iliac crest, periosteum, dental pulp and intraoral sites. Conclusions: The very small amount of available data makes it impossible to draw any firm conclusions regarding the increase in bone formation in human oral reconstructive procedures when using graft materials engineered with autogenous stem cells.

The fabrication and tribological behavior of epoxy composites modified by the three-dimensional polyurethane sponge reinforced with dopamine functionalized carbon nanotubes

Three-dimensional (3D) interpenetrating network structure epoxy composites were fabricated based on the modified carbon nanotube (CNT) reinforced flexible polyurethane (PU) sponge. CNTs were first functionalized with polydopamine (PDA) as revealed by TEM imaging, which is formed via the oxidative self-polymerization of dopamine. Then the functionalized CNTs (CNT–PDA) were successfully anchored on the skeleton surfaces of sponge, forming a continuous 3D carbon network. The interfacial interaction between modified PU sponge and epoxy (EP) matrix was significantly enhanced due to the covalent linkage of PDA. Improvement in the thermal stability of CNT–PDA/PU3D/EP composites was observed by TG analysis and related to the CNTs anchored on the skeleton of sponge. The tribological properties of pure EP, PU3D/EP and CNT–PDA/PU3D/EP composites were comparatively investigated in terms of different loads and velocities. Results demonstrated that CNT–PDA/PU3D/EP composites exhibited the best tribological performance owing to the strong interfacial interaction and the 3D carbon network structure. In particular, the wear resistance of CNT–PDA/PU3D/EP composites was 6.2 times and 3 times higher than those of pure EP and PU3D/EP composites under the applied load of 1.6MPa, respectively.

Biosynthesis of succinoglycan by Agrobacterium radiobacter NBRC 12665 immobilized on loofa sponge and cultivated in sugar cane molasses. Structural and rheological characterization of biopolymer

Succinoglycans are heteropolysaccharides synthesized by bacteria. It possesses thickening and texturizing properties, making it useful in a number of applications in food, pharmaceutical and chemical industries. Agrobacterium radiobacter NBRC 12665 cells were immobilized in the loofa sponge matrix and used to produce succinoglycan. Production of the biopolymer using the substrates sugar cane molasses, sucrose, glucose and lactose at concentrations of 2.5%, 5.0% and 7.5% for eight days was analyzed. The best results were obtained using sugar cane molasses (14.0g/L) and lactose (12g/L) at 7.5% with immobilized cells. Under optimum conditions, it was possible to re-use the matrix to produce succinoglycan in five consecutive eight day operating cycles. Scanning electron microscopy and Fourier Transform Infrared Spectroscopy (FTIR) confirmed the immobilization of the microorganism in the loofa sponge. FTIR of the biopolymer revealed the presence of residues of carbohydrate and carboxylic groups. The use of mixed ions exchange resin for removal of the succinoglycan pigments from molasses resulted in a depigmentation of 74% in the color of the biopolymer and 65% in its turbidity. Succinoglycans obtained from lactose and sugar cane molasses exhibited molecular weights of 2.734ÿ106g/mol and 2.326ÿ106g/mol, respectively. Rheological analysis of the succinoglycans in terms of concentration (0.5⿿2.0%), temperature (5⿿75°C) and pH (2.5⿿10.0) revealed non-Newtonian and shear thinning behavior of the biopolymer. The technique of immobilization in loofa sponge and use of sugar cane molasses as a low cost carbon source produced significant and effective results for the industrial production of succinoglycan.

Characterization of curdlan produced by Agrobacterium sp. IFO 13140 cells immobilized in a loofa sponge matrix, and application of this biopolymer in the development of functional yogurt.

Agrobacterium sp. IFO 13140 cells were immobilized on a loofa sponge and used to produce curdlan over five successive cycles. The interaction between microbial cells and the loofa sponge as well as the produced curdlan were characterized by Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectrometry. The purity of the curdlan was also evaluated. The storage stability of the immobilized cells was assessed and the produced curdlan was used in a functional yogurt formulation. The average curdlan production by immobilized cells was 17.84 g L(-1) . The presence of the microorganism in the sponge was confirmed and did not cause alterations in the matrix, and the chemical structure of the curdlan was the same as that of commercial curdlan. The purity of both was similar. The immobilized cells remained active after 300 days of storage at -18 °C. The use of the produced curdlan in a functional yogurt resulted in a product with lower syneresis. A large number of cells physically adhered to the surface of loofa sponge fibers, and its use as an immobilization matrix to produce curdlan was effective. The use of the produced curdlan in yogurt allowed the development of a more stable product. © 2015 Society of Chemical Industry.