Type Of Sponge Research Articles

Nanocomposite sponge based on sodium alginate, polyvinyl alcohol, carbon dots, and woolly hedge nettle antibacterial extract for wound healing

Skin ulcers associated with significant bleeding and bacterial infections can be life-threatening and pose significant challenges in clinical settings. To solve this problem, there is an increasing need for biomaterials that have hemostatic and antibacterial properties. Such biomaterials are highly desirable as they could help to promote wound healing and prevent infections, thus improving patient therapeutic outcomes. Inspired by this content, a new type of nanocomposite sponge based on sodium alginate (SA) and polyvinyl alcohol (PVA) was created with the combination of carbon dots (CDs) and woolly hedge nettle extract (HNE) as an antibacterial and hemostatic wound dressing. The prepared samples were characterized by different techniques. The properties of CDs were determined by FT-IR and XRD. SEM confirmed the creation of porous and interconnected structures. The developed nanocomposite sponge showed suitable physicochemical properties such as hydrophilicity, water vapor transmission rate, water absorption, and mechanical properties. Also, the cytotoxicity and hemolysis percentage of these sponges were within the permissible range. In addition, the antibacterial activity of the sponges increased by adding HNE. Finally, In vivo studies showed that these sponge nanocomposites can have a potential healing function for wound dressing applications.

Screening of Haliclona sp. symbiont bacteria that have the potential as MDR (Multidrug-Resistant) antibacterial from Tanjung Tiram Beach

Sponge Haliclona sp. is a type of sponge living in marine waters and is found in many areas of coral reef ecosystems. This study aimed to determine the potential for sponge Haliclona sp. obtained from Tanjung Tiram waters, Konawe, as a source of bioactive compounds of MDR (Multidrug-Resistant) antibacterial. The isolation method of Haliclona sp. symbiont was carried out by pouring and purification of Haliclona sp. symbiont using the scratch method. The purification results obtained 12 isolates of symbiont bacteria that were successfully isolated. Then the bacterial isolate was tested for its antibacterial ability against MRSA and ESBL Escherichia coli bacteria qualitatively using the agar diffusion method. Bacteria that have strong inhibitory activity are identified by morphological and biochemical tests. The results of the qualitative screening test produced four bacterial isolates that have inhibitory activity against MRSA (Methicilin Resistant Staphylococcus aureus) pathogenic bacteria with the isolate codes H3 and H8 belonging to the strong category while H4 and H10 belonging to the medium categoy. Additionally, two bacterial isolates that have inhibitory activity against ESBL Escherichia coli pathogenic bacteria with the isolate codes H3 and H8 belonging to the strong category. Based on morphological observations and biochemical tests, the H3 bacterial isolate was identified as the genus Corynebacterium spp. and the H8 bacterial isolate was identified as the genus Micrococcus spp. In conclusion, Haliclona sp. sponge exhibits promising potential as a source of microorganism producing antibacterial compounds, particulary againts MDR (Multidrug-Resistant) strains.

Influence of Lavender Essential Oil on the Physical and Antibacterial Properties of Chitosan Sponge for Hemostatic Applications.

Uncontrollable bleeding continues to stand as the primary cause of fatalities globally following surgical procedures, traumatic incidents, disasters, and combat scenarios. The swift and efficient management of bleeding through the application of hemostatic agents has the potential to significantly reduce associated mortality rates. One significant drawback of currently available hemostatic products is their susceptibility to bacterial infections at the bleeding site. As this is a prevalent issue that can potentially delay or compromise the healing process, there is an urgent demand for hemostatic agents with antibacterial properties to enhance survival rates. To mitigate the risk of infection at the site of a lesion, we propose an alternative solution in the form of a chitosan-based sponge and antimicrobial agents such as silver nanoparticles (AgNPs) and lavender essential oil (LEO). The aim of this work is to provide a new type of hemostatic sponge with an antibacterial barrier against a wide range of Gram-positive and Gram-negative microorganisms: Staphylococcus epidermidis 2018 and Enterococcus faecalis VRE 2566 (Gram-positive strains) and Klebsiella pneumoniae ATCC 10031 and Escherichia coli ATCC 35218 (Gram-negative strains).

Carbon Dots for Improving Water and Oil Absorption of Sponges

An oil spill is one of the hazardous problems in the ocean. Cleaning the oil spill requires expensive and specific technologies. Nowadays, advanced techniques such as skimmers, oil dispersion agents, in-situ burning and solar-heated oil-absorbent are frequently used to solve the problem. For oil-absorbent materials, further, development is still required to enhance oil dan water absorption. Carbon dots is one of the promising nanoparticles that can be used to improve oil absorption. In this work, we conjugated carbon dots made of pencil leads into several types of sponges. The purpose of this work was to improve oil and water absorption. Our experiment results showed that 2 to 5 nanometres size of ethanol soluble carbon dots were successfully synthesized using a simple electrochemical process. UV-Vis absorption and FTIR spectra showed clear energy transition and functional groups in carbon dots. We used six different sponges with various mass densities from 9 to 174 mg/cm3. Conjugation of carbon dots into the sponge was simply done by immersing the sponge in carbon dot solution and drying it. The conjugation made the mass of the sponge increase. We examined the water and oil absorption capacity of each sponge. Oil absorption capacities were different for each sponge. In general, the addition of carbon dots in sponges increased the mass density of sponge water twice. Furthermore, one type of sponge decreased oil absorption capacity after carbon dots conjugation. Other types of sponges showed an improvement of oil absorption capacity by 60% after carbon dot conjugation. We believe that this work can be further improved to get higher water and oil absorption.

Emerging roles of circRNAs in leukemia and the clinical prospects: An update.

Circular RNAs (circRNAs) are a new category of endogenous non-protein coding RNAs (ncRNAs), and show the characteristics of high conservation, stability, and tissue specificity. Due to rapid advances in next-generation sequencing and transcriptome profiling technologies, circRNAs have been widely discovered in many organisms and participated in the development and progress of a variety of diseases. As a type of molecular sponge, circRNAs mainly absorb micro RNAs competitively and interplay with RNA-binding proteins to modulate the splicing as well as transcription of target genes. This review is based on a literature search using the Medline database. Search terms used were "circular RNAs and leukemia," "circRNAs and leukemia," "circRNAs and acute lymphoblastic leukemia," "circRNAs and chronic lymphoblastic leukemia," "circRNAs and acute myeloid leukemia," "circRNAs and chronic myeloid leukemia," and "circRNAs, biomarker, and hematological system." CircRNAs have been proven as potential biomarkers and therapeutic targets in a variety of tumors. Recent research has found that circRNAs aberrantly exist in hematological cancers, especially leukemia, and are significantly associated with the incidence, progress, and metastasis of diseases as well as the prognosis of patients. The current work summarizes the latest findings on circRNAs in various types of leukemia, aiming to propose prospective therapies and new drug screening methods for the treatment of leukemia.

Optimization of a lattice structure inspired by glass sponge

The biomimetic design of engineering structures is based on biological structures with excellent mechanical properties, which are the result of billions of years of evolution. However, current biomimetic structures, such as ordered lattice materials, are still inferior to many biomaterials in terms of structural complexity and mechanical properties. For example, the structure of Euplectella aspergillum, a type of deep-sea glass sponge, is an eye-catching source of inspiration for biomimetic design, many researches have introduced similar architecture in cellular solids. However, guided by scientific theory, how to surpass the mechanical properties of E. aspergillum remains an unsolved problem. We proposed the lattice structure which firstly surpass the E. aspergillum mechanically. The lattice structure of the skeleton of E. aspergillum consists of vertically, horizontally, and diagonally oriented struts, which provide superior strength and flexural resistance compared with the conventional square lattice structure. Herein, the structure of E. aspergillum was investigated in detail, and by using the theory of elasticity, a lattice structure inspired by the biomimetic structure was proposed. The mechanical properties of the sponge-inspired lattice structure surpassed the sponge structure under a variety of loading conditions, and the excellent performance of this configuration was verified experimentally. The proposed lattice structure can greatly improve the mechanical properties of engineering structures, and it improves strength without much redundancy of material. This study achieved the first surpassing of the mechanical properties of an existing sponge-mimicking design. This design can be applied to lattice structures, truss systems, and metamaterial cells.

PENGGUNAAN SANDAL KHUSUS UNTUK PENCEGAHAN KEAUSAN BATU CANDI BOROBUDUR

The use of mass tourism has several negative impacts on the preservation of Borobudur Temple. One of them is the condition of wear and tear on the stone stairs and floors. From the survey results and calculation of the percentage of stone wear of Borobudur Temple on the west and north side of the stone stairs are 63.39% and 27.84%, while on the south side stone stairs are 30.96%. One of the efforts to minimize wear and tear is the use of special sandals. This particular sandal study aims to obtain a prototype of footwear (sandals) that meet the criteria for durability, ergonomics and visual harmony (DEKS), as well as an effort to increase community participation through empowering local MSMEs (Micro, Small and Medium Enterprises). The research method went through two stages, namely: laboratory testing of sandal material samples, and the manufacture of special sandals. The results of the study concluded that the use of sandals can have an effect on efforts to prevent an increase in the power of the temple stones on the stairs and floors. Friction test results show that the type of sponge material has a lower level of hardness than the type of stone sponge, so it has a low impact on wear. Based on the criteria required in the formulation of the problem, the prototype design is made in three types, namely; prototypes I, II and III. This particular sandal is designed with the brand “Upanat Barabudur”. Taken from the inscription on the relief of Karmawibhangga panel 150 which means 'footwear'. Viewed from the perspective of historical and philosophical values, the use of special footwear is useful in an effort to minimize wear and tear and as a conservation education medium for visitors.

Stylotella Sp. Acetone Extract from Selayar Island and Its Activity against Breast Cancer Cells MCF-7

Styletella sp. is a type of sponge in the Halichondriidae family which is rich in secondary metabolite compounds that have various bioactivities that have the potential as drugs in the future, one of which is anticancer. This study aims to determine the types of secondary metabolites found in Stylotella sp. in Selayar Island and to determine the secondary metabolite bioactivity of MCF-7 breast cancer cells. The method used is extraction using acetone, fractionation and purification. The purity test was carried out by testing three eluent systems at TLC, namely chloroform:ethyl acetate (9:1), n-hexane: acetone (8:2), chloroform: acetone (9:1) eluent. Then qualitatively and characterized by FTIR spectrophotometer. The results showed that pure isolates contained alkaloid compounds. The MCF-7 cell activity test showed an IC50 value for acetone extract of 1452.38 g/mL which has potential anticancer activity and an IC50 value for pure isolate acetone extract of 14983.52 g/mL.

Iron-Rich Salt and Antioxidants from Sea Sponge with Added Moringa Leaves as Potential Food Ingredients in Efforts to Alleviate Anemia

Based on the high prevalence of anemia of more than 24% population affected, the natural potential of Indonesia such as Sponge and Moringa leaves to be a salt product high in iron, and interconnection between this theoretical science and Islamic studies related to the utilization of natural materials, we want to explore how potential be a product that can be one of the efforts to alleviate anemia. Initial data collection to explore sponge types and types of plants rich in iron was done using data search portal NCBI (National Center for Biotechnology Information, USA) in the last five years starting from 2016/03/30 to 2021/03/28. Samples were formulated based on the comparison of seawater, sponge (Spongia sp), and moringa leaves in a composition as follows: Sample A (1:1:0.05), sample B (1:1:0.25), sample C (1:1:0.5) and control that did not use the addition of Moringa leaves (1:1). The analysis included testing antioxidant activity using DPPH, moisture content, NaCl, impurities sulfate, magnesium, calcium, and iron levels which were all done in three repetitions of each sample or triplicates and using analytical methods from the Association of Official Analytical Chemists (AOAC).Sponge sp is a type of sea sponge that is easy to find in the Indonesian country and can be combined with moringa leaves whose availability is also abundant in Indonesia, as a potential salt high in iron. This study obtained salt granules as much as 0.92 ± 0.22 kg. There was no difference in the results of salt granules from each sample, and there was no difference in the level of fineness of salt granules, namely 20-35 mesh or equivalent to crude salt. However, there were differences in the level of chemical it contains. Samples B, C, and control correspond to SNI 3556:2016 based on percentage of moisture content, Fe, calcium impurities, sulfate impurities, and magnesium impurities in all three samples. However, it is known that sample C is the one that has the highest iron levels compared to B and control samples, which means that sample C is the best sample and has antioxidant activity that is in line with the purpose of this study, which is an effort to alleviate iron deficiency anemia. This salt is also a salt that is Halal Tayyiban, which means not only halal but also good and healthy if consumed.

DAYA HAMBAT EKSTRAK CALLYSPONGIA SP. TERHADAP BAKTERI DARI Eucheuma Cottoni BERPENYAKIT Ice-Ice

Callyspongia sp. is one type of sea sponge that produces secondary metabolites in the form of steroids, alkaloids, flavonoids, and terpenoids which can be used as antibacterial agents. This reseach aims to determine whether or not there is an inhibitory power of sea sponge extract Callyspongia sp. on the growth of bacterial isolates on Eucheuma cottonii seaweed that is infected by ice-ice disease. This type of research is an experimental laboratory. Extract of Callyspongia sp. is the result of Callyspongia sp. extraction which has been dried and then macerated using a polar ethanol solvent. Inhibition test with the modified Kirby-Bauer method used wells to measure the zone of inhibition formed by the extract of the Callyspongia sp. The test was carried out to observe the presence or absence of an inhibition zone of Callyspongia sp. extract against bacterial isolates (Isolates I, II and III) that is infected by seaweed that is infected by ice-ice disease after 24 hours of incubation. The results showed that an inhibition zone was formed in bacterial isolates. Treatment with extracts of Callyspongia sp. shows the diameter of the highest inhibition zone that is 16.67 mm which is classified as a strong inhibitory force, so that Callysponia sp. extract has the potential in overcoming ice-ice in Eucheuma cottonii seaweed.

Preparation and evaluation of chitosan-polyvinyl alcohol/polyhexamethylene guanidine hydrochloride antibacterial dressing to accelerate wound healing for infectious skin repair.

BackgroundWound infections, especially multidrug-resistant (MDR) bacterial infections, are a major challenge in clinical medicine.MethodsIn this study, a new type of antibacterial sponge was prepared from a solution containing a chitosan-polyvinyl alcohol (CTS-PVA) emulsion with added polyhexamethylene guanidine hydrochloride (PHMG) in a homogeneous medium using lyophilization technology. The antibacterial ability of and CTS-PVA/PHMG sponge against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Candida albicans, Methicillin-resistant Staphylococcus aureus, multidrug-resistant Pseudomonas aeruginosa, and multidrug-resistant Acinetobacter baumannii in vitro. The structure and physical properties were characterized. The sponge dressing was tested in a Pseudomonas aeruginosa-infected full-thickness mouse skin wound defect model. The effects were evaluated by wound area measurement and histological analysis.ResultsThe CTS-PVA/PHMG sponge showed broad-spectrum antibacterial ability, including for MDR bacterial stains from clinical sources, while maintaining excellent physicochemical properties, including a high swelling degree and good moisture retention capability. Scanning electron microscopy images displayed the surface morphology of the CTS-PVA/PHMG sponge dressing. The detection of the wound healing rate and histological analysis supported that the new dressing can alleviate the inflammation and accelerate the healing speed of infected wounds and in vivo.ConclusionsCTS-PVA/PHMG sponge shows broad-spectrum antibacterial activity, which can provide a new pathway for clinical prevention and treatment of superbug-infected wounds.

Dishwashing sponges and brushes: Consumer practices and bacterial growth and survival

Sponges are frequently used in kitchens and have been shown to harbor large numbers of bacteria, occasionally also pathogens. Less is known about kitchen brushes regarding usage and presence of bacteria. In the present study, the use of sponges and brushes was studied in a survey among 9966 European consumers in ten countries, and growth and survival of bacteria in sponges and brushes were examined in laboratory experiments.Sponges were the preferred hand-cleaning utensils for washing-up in the majority of countries, while brushes were most frequently used in Denmark and Norway. Consumers mostly change their sponges at regular times, but also sensory cues (looks dirty, smelly, slimy) and usage occurrences such as wiping up meat juices may trigger replacement. Besides cleaning the dishes, over a quarter of the dish brush users also use it to clean a chopping board after soilage from chicken meat juices.The water uptake and drying rate varied considerably, both between different sponges and between brushes and sponges, where brushes dried fastest. Campylobacter survived one day in all sponges and Salmonella more than seven days in two of three types of sponges. In the type of sponge that dried slowest, Salmonella grew on the first day and was always found in higher levels than in the other sponges. Non-pathogenic bacteria grew in the sponges and reached levels around 9 log CFU/sponge. In brushes all types of bacteria died over time. Campylobacter and Salmonella were reduced by more than 2.5 log to below the detection limit after one and three days, respectively. Bacteriota studies revealed a tendency for a dominance by Gram-negative bacteria and a shift to high relative prevalence of Pseudomonas over time in sponges. Both enumeration by agar plating and bacteriota analysis confirmed that the pathogens were in a minority compared to the other bacteria.Treatments of sponges and brushes with chlorine, boiling or in the dishwasher were effective to reduce Salmonella.We conclude that brushes are more hygienic than sponges and that their use should be encouraged. Contaminated sponges or brushes should be replaced or cleaned when they may have been in contact with pathogenic microorganisms, e.g. used on raw food spills. Cleaning of sponges and brushes with chlorine, boiling or dishwasher may be a safe alternative to replacing them with new ones.

Flexible Water-Absorbing Silk-Fibroin Biomaterial Sponges with Unique Pore Structure for Tissue Engineering.

Silk fibroin (SF) scaffolds are widely used in tissue engineering due to their biocompatibility and slow biodegradability. However, the relatively stiff mechanical properties and low permeability of these systems can limit some applications. In this study, a new type of water-stable silk sponge (ASF-PEG-S) was obtained by inducing nanoparticle (50-300 nm in diameter) formation in SF solution by autoclaving followed by freeze-drying and rinsing the dry sponges with low-molecular weight (400 Da) polyethylene glycol (PEG400) to induce SF β-sheet structure formation and thus stability in water. With further extraction, the SF nanoparticles embedded in the sponges were removed, leaving nanopores in the walls of round-shaped micro-size pores. The unique pore structure resulted in enhanced permeability and flexibility of ASF-PEG-S when compared to other types of SF sponges, especially with respect to commonly used methanol-annealed SF sponges. In addition, ASF-PEG-S absorbed water nearly 40 times more than its dry weight, while the methanol-annealed sponges absorbed half this amount. When human fibroblasts were seeded and cultured on ASF-PEG-S versus traditional SF methanol-processed sponges, improved cell encapsulation, distribution, and consistency in growth were observed, suggesting utility in tissue engineering and tissue repair applications in the future.

1,10‐Phenanthrolin‐1‐ium Trinitromethanide (1,10‐PHTNM) as a Nano Molten Salt Catalyst With Y‐Aromatic Counter Ion: Applications for Synthesis of Organic Compounds

Abstract1,10‐Phenanthrolin‐1‐ium trinitromethanide (1,10‐PHTNM) as a novel nano molten slat with Y‐aromatic counter ion was synthesized and fully characterized by using various techniques such as FT‐IR, 1H NMR, 13C NMR, mass, TGA, DTG, XRD, SEM and TEM. A series of organic compounds include 1,4‐dihydropyrano[2,3‐c]pyrazoles, tetrahydrobenzo[b]pyran, pyrano[4,3‐b]pyrans, bispyrazole, 1H‐pyrazolo[3,4‐b]quinolones, hexahydroacridine‐1,8‐diones and methylenebis(3‐hydroxy‐5,5‐dimethylcyclohex‐2‐enones) were synthesized in the presence of 1,10‐PHTNM as a novel and efficient proton sponge nano molten slat catalyst. According to the results of FT‐IR, 1H NMR, 13C NMR, mass spectrum of 1,10‐PHTNM and due to high electron charge density and none bonded repulsion of lone pair electrons between two nitrogen atoms (peri‐effect), this catalyst is a type of proton sponge.

Selective Separation of Lead Ions Using New Nano-Adsorbent GH-92

One of the main sources of environment pollution is the industrial wastewater which contains heavy metals and can be found in many industries. If these heavy metals enter in the human body, would cause many health problems. On the other hand, different researches around the world show that nanotechnology is an effective way to remove pollutants. In this research, for the first time in the world, a type of natural sponge of Persian Gulf that has Nano holes has been used to remove the lead ion selectively from calcium, magnesium and cobalt ions in aqueous solution. The present study identified a sample belonging to the sponge of Demospongiae class. The aggregation of absorption in the sponge, contact time, particle size and by measuring environment`s pH were measured. The results show this type of sponge, GH-92, is able to absorb different amounts of mentioned metal ions. Adsorption amount of calcium, magnesium and cobalt by this type of sponge was very small. The highest adsorption capacity belonged to lead ion in pH= 4.5 to 5 with mesh 230 which was 79.19 mg per gram of adsorbent. This is the highest adsorption capacity of lead comparison with reported articles for selective separation of lead ion.

* Early and Marked Enhancement of New Bone Quality by Alendronate-Loaded Collagen Sponge Combined with Bone Morphogenetic Protein-2 at High Dose: A Long-Term Study in Calvarial Defects in a Rat Model.

Choice of appropriate biomaterial is a key factor for the success of recombinant human bone morphogenetic protein (rhBMP)-2 therapy. Inspired by osteogenic cell-differentiating and osteoclast-suppressing capabilities of alendronate (ALN), we manufactured a composite type of ALN-loaded collagen sponge (ALN-CS), which controls the early detrimental effect of high-dose rhBMP-2. This study aimed to evaluate ALN-CS as a high-dose rhBMP-2 carrier by investigating its initial biomolecular effect and efficacy on intramembranous ossification at 1, 4, 8, and 24 weeks using a rat calvarial defect model compared with nonloaded CS. The in vitro rhBMP-2 release in the ALN-CS showed a low initial burst and steady release phase during the rest period despite lack of calcium compared with that in CS alone. ALN release showed the same tendency as rhBMP-2 release. In vitro characterization showed that osteoblast differentiation and mineralization of mesenchymal stromal cells were more enhanced with ALN-CS. The ALN-CS-BMP group showed higher expression of bone-forming and -resorbing markers in vivo than the CS-BMP group after the first 7 days, which might be attributable to the relatively large amount of rhBMP-2 remaining. However, osteoclast activation in the ALN-CS-BMP group was significantly reduced compared with the CS-BMP group. Radiological and histological analyses revealed that ALN-CS-BMP promoted early and dense ossification at the initial defect, with 100% greater bone mass, 20% greater bone density, and less fatty marrow tissue than CS-BMP, which continued during the whole healing period. However, CS or ALN-CS alone failed to show complete defect closure even at the 24-week healing interval. Our results demonstrate that ALN-CS has remarkable advantages over CS alone in high-dose BMP-2 delivery, with potent suppression of resorption, early and dense ossification at the target area with less fatty marrow formation, and continuation of bone quality over the long term, which highlights its great clinical potential as a rhBMP carrier for bone regeneration at intramembranous ossification sites.

The End Is Not the End: Remnants of tRNA Precursors Live On to Sponge Up Small Regulatory RNAs

Natural RNA sponges sequestering cellular noncoding RNA molecules have been found in diverse organisms. In this issue, Lalaouna et al. (2015) report another type of RNA sponge, showing that stable intermediates of bacterial tRNA processing control endogenous small RNAs.

Culture of bovine articular chondrocytes in funnel-like collagen-PLGA hybrid sponges**This work was presented at the International Union of Materials Research Societies (International Conference in Asia) (Qingdao, China, Sep. 25–28 2010).

Three-dimensional porous scaffolds play an important role in tissue engineering and regenerative medicine. Structurally, these porous scaffolds should have an open and interconnected porous architecture to facilitate a homogeneous cell distribution. Moreover, the scaffolds should be mechanically strong to support new tissue formation. We developed a novel type of funnel-like collagen sponge using embossing ice particulates as a template. The funnel-like collagen sponges could promote the homogeneous cell distribution, ECM production and chondrogenesis. However, the funnel-like collagen sponges deformed during cell culture due to their weak mechanical strength. To solve this problem, we reinforced the funnel-like collagen sponges with a knitted poly(D,L-lactic-co-glycolic acid) (PLGA) mesh by hybridizing these two types of materials. The hybrid scaffolds were used to culture bovine articular chondrocytes. The cell adhesion, distribution, proliferation and chondrogenesis were investigated. The funnel-like structure promoted the even cell distribution and homogeneous ECM production. The PLGA knitted mesh protected the scaffold from deformation during cell culture. Histological and immunohistochemical staining and cartilaginous gene expression analyses revealed the cartilage-like properties of the cell/scaffold constructs after in vivo implantation. The hybrid scaffold, composed of a funnel-like collagen sponge and PLGA mesh, would be a useful tool for cartilage tissue engineering.

Three‐dimensional honeycomb‐patterned chitosan/poly(L‐lactic acid) scaffolds with improved mechanical and cell compatibility

Micro-size patterned surfaces trigger specific biological responses such as the promotion of cell growth, cell migration, cell differentiation, and ECM production. The aim of this work was to elaborate three-dimensional scaffolds with honeycomb patterned surfaces and large open pores, and to study the influence of surface patterning on cell behavior. In this study, we used water droplets as porogen material to prepare a novel type of chitosan sponge with large open pores on its surface. The sponges obtained were then immersed into 6 wt % Poly(L-lactic acid) chloroform solution to obtain honeycomb patterned composite porous scaffolds. The morphology and mechanical properties were characterized with SEM and compression testing. The fibroblast behaviors in scaffolds were analyzed with SEM, VG, PAS, live-dead staining, and flow cytometer. Results showed that these composite scaffolds possessed better mechanical properties and hierarchical porous structure than pure chitosan sponges. Cell culture revealed that the honeycomb patterned surface had positive influences on fibroblast behaviors, wherein the cell adhesion, proliferation, ECM secretion and viability were improved dramatically. Such a hierarchical composite scaffold would be a suitable candidate for tissue engineering purposes.

Structural changes and biodegradation of PLLA, PCL, and PLGA sponges during in vitro incubation

AbstractThe structural changes and degradation behaviors of poly(L‐lactic acid) (PLLA) and poly(ε‐caprolactone) (PCL) sponges were studied by incubation in phosphate buffer solution and compared with those of previously reported poly(lactic‐co‐glycolic acid) (PLGA) sponge. The changes of pH, weight, molecular weight, crystallinity, and thermal properties of glass transition and melting were measured. The influence of incubation temperature on the structural change of each type of sponge was investigated in details. During incubation, the PLLA sponge showed secondary crystallization, the PCL sponge showed lamellar thickening, and the PLGA sponge showed physical aging. Depending on the type of biodegradable polymers, the incubation temperature caused different structural changes during the incubation and the structural changes influenced several degradation behaviors. POLYM. ENG. SCI., 50:1895–1903, 2010. © 2010 Society of Plastics Engineers