Mechanical properties of calcium alginate fibers produced with a microfluidic device

The cytotoxicity and anti-influenza virus (IFV) activity of calcium or zinc alginate fibers were investigated to explore the feasibility of them to be used as biomaterials. African Green Monkey kidney cell (Vero) and human cervical cancer cell (Hela) cultured with alginate fibres were used to screen cytotoxic effects. After 48 h, MTT (3-(4,5-dimethyl-2-thiazol)-2,5-diphenyl-2H tetrazolium bromide) assays were performed. Then cytotoxicity was evaluated with six grades according to cell relative growth rate (RGR). In anti-IFV activity assay, IFV were added to all fibers and the Vero cell survival were detected by MTT assays with calculating the percentage of protection. The cytotoxity of calcium alginate fibers on Vero were grade 0 or 1 in contrast to zinc alginate fibers which was grade 0. The cytotoxity of calcium or zinc alginate fibers on Hela were grade 0. Furthermore, partial calcium or zinc alginate fibers could promote Vero or Hela cell growth. In antiviral assay the highest percentage of protection of calcium alginate fibers was 34.42%, while that of zinc alginate fibers was 59.42%. The results showed that calcium or zinc alginate fibers had a good cellular biocompatibility and the large weight zinc alginate fibers had a better anti-IFV activity than calcium alginate fibers, which is potential for tissue engineering.

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The Combined Effects of Co-Culture and Substrate Mechanics on 3D Tumor Spheroid Formation within Microgels Prepared via Flow-Focusing Microfluidic Fabrication

Pharmaceutics ◽

10.3390/pharmaceutics10040229 ◽

2018 ◽

Vol 10 (4) ◽

pp. 229 ◽

Cited By ~ 11

Author(s):

Dongjin Lee ◽

Chaenyung Cha

Keyword(s):

Mechanical Properties ◽

Cell Culture ◽

Microfluidic Device ◽

3D Cell Culture ◽

Breast Adenocarcinoma ◽

Adherent Cell ◽

Flow Focusing ◽

Spheroid Formation ◽

3D Scaffold ◽

Tumor Spheroids

Tumor spheroids are considered a valuable three dimensional (3D) tissue model to study various aspects of tumor physiology for biomedical applications such as tissue engineering and drug screening as well as basic scientific endeavors, as several cell types can efficiently form spheroids by themselves in both suspension and adherent cell cultures. However, it is more desirable to utilize a 3D scaffold with tunable properties to create more physiologically relevant tumor spheroids as well as optimize their formation. In this study, bioactive spherical microgels supporting 3D cell culture are fabricated by a flow-focusing microfluidic device. Uniform-sized aqueous droplets of gel precursor solution dispersed with cells generated by the microfluidic device are photocrosslinked to fabricate cell-laden microgels. Their mechanical properties are controlled by the concentration of gel-forming polymer. Using breast adenocarcinoma cells, MCF-7, the effect of mechanical properties of microgels on their proliferation and the eventual spheroid formation was explored. Furthermore, the tumor cells are co-cultured with macrophages of fibroblasts, which are known to play a prominent role in tumor physiology, within the microgels to explore their role in spheroid formation. Taken together, the results from this study provide the design strategy for creating tumor spheroids utilizing mechanically-tunable microgels as 3D cell culture platform.

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RECIRCULACIÓN DE LÍQUIDOS RESIDUALES EN LA CONVERSIÓN DE ALGINATO DE CALCIO EN ÁCIDO ALGÍNICO DURANTE EL PROCESO DE PRODUCCIÓN DE ALGINATOS

CICIMAR Oceánides ◽

10.37543/oceanides.v20i1-2.17 ◽

2005 ◽

Vol 20 (1-2) ◽

pp. 1

Author(s):

Y. E. Rodríguez-Montesinos ◽

G. Hernández-Carmona ◽

D. L. Arvizu-Higuera

Keyword(s):

Calcium Alginate ◽

Alginic Acid ◽

Current System ◽

Macrocystis Pyrifera ◽

Alginate Production ◽

Yield And Quality ◽

Alginate Fibers ◽

Counter Current ◽

Very High

Se estudió el efecto de recircular la solución ácida residual en la etapa de conversión de alginato de calcio en ácido algínico, utilizando el alga Macrocystis pyrifera . Los líquidos residuales fueron reciclados en un sistema en contra corriente, con lo cual se logró procesar tres cargas de alginato de sodio con el mismo volumen de agua, permitiendo una conversión efectiva en ácido algínico, con una reducción del 56% en el consumo de agua dulce. Se experimentó un sistema de recirculación en línea (sin reemplazo de agua), este sistema no es recomendable, debido a que la acumulación de calcio en el alginato después de la segunda recirculación, produce una viscosidad aparente muy alta, con un porcentaje de reducció superior al 50%. Se determinó el efecto del número de lavados ácidos del ácido algínico sobre la calidad y rendimiento del alginato obtenido. El tratamiento ácido se llevó a cabo con tres, dos y un lavado. Se concluye que se requieren tres lavados de las fibras de alginato de calcio para lograr una conversión efectiva en ácido algínico, pero el primero y segundo lavado se pueden hacer con ácido reciclado. Es tesis tema representa un ahorro del 66% en el consumo de agua en esta etapa. Recycling of residual liquids from the conversion of calcium alginate to alginic acid during alginate production process The effect of recycling the residual acid solution from the conversion of calcium alginate to alginic acid from the alga Macrocystis pyrifera was studied. The residual liquid was recycled using a counter current system; it was possible to treat three batches of calcium alginate with the same amount of water, with an effective conversion into alginic acid, saving 56% of fresh water. An inline recycling system was experimented (without water replacement). This system is not recommended, because the large increase of calcium in the alginate after the second recycling, produces a very high apparent viscosity. Using this system the viscosity was reduced in more than 50%. We experimented the effect of the number of acid washings of the alginic acid, on the yield and quality of the final alginate. The acid treatment was carried out with three, two and one washing. It was concluded that three acid washings of the calcium alginate fibers are necessary to obtain an effective conversion of calcium alginate to alginic acid, but the first and second washings can be carried out with recycled acid. This system represents a water saving up to 66% in this step.

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Design for dynamic hydrogen bonding in a double network structure to improve the mechanical properties of sodium alginate fibers

New Journal of Chemistry ◽

10.1039/d1nj03268b ◽

2021 ◽

Author(s):

Ming Yan ◽

Junfeng Shi ◽

Song Tang ◽

Guohang Zhou ◽

Jiexiang Zeng ◽

...

Keyword(s):

Mechanical Properties ◽

Hydrogen Bonding ◽

Sodium Alginate ◽

Network Structure ◽

Wet Spinning ◽

Double Network ◽

Alginate Fibers

The SA/PAA-VSNP fiber was obtained using dynamic wet spinning through dynamic hydrogen bonding in the double network structure.

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Electrospun Alginate Fibers: Mixing of Two Different Poly(ethylene oxide) Grades to Improve Fiber Functional Properties

Nanomaterials ◽

10.3390/nano8120971 ◽

2018 ◽

Vol 8 (12) ◽

pp. 971 ◽

Cited By ~ 9

Author(s):

Barbara Vigani ◽

Silvia Rossi ◽

Giulia Milanesi ◽

Maria Bonferoni ◽

Giuseppina Sandri ◽

...

Keyword(s):

Mechanical Properties ◽

Ethylene Oxide ◽

Electrospinning Process ◽

Mechanical Resistance ◽

Fiber Morphology ◽

Chain Entanglement ◽

Poly Ethylene Oxide ◽

Alginate Fibers ◽

Poly Ethylene ◽

Morphology And Mechanical Properties

The aim of the present work was to investigate how the molecular weight (MW) of poly(ethylene oxide) (PEO), a synthetic polymer able to improve alginate (ALG) electrospinnability, could affect ALG-based fiber morphology and mechanical properties. Two PEO grades, having different MWs (high, h-PEO, and low, l-PEO) were blended with ALG: the concentrations of both PEOs in each mixture were defined so that each h-PEO/l-PEO combination would show the same viscosity at high shear rate. Seven ALG/h-PEO/l-PEO mixtures were prepared and characterized in terms of viscoelasticity and conductivity and, for each mixture, a complex parameter rH/rL was calculated to better identify which of the two PEO grades prevails over the other in terms of exceeding the critical entanglement concentration. Thereafter, each mixture was electrospun by varying the process parameters; the fiber morphology and mechanical properties were evaluated. Finally, viscoelastic measurements were performed to verify the formation of intermolecular hydrogen bonds between the two PEO grades and ALG. rH/rL has been proved to be the parameter that better explains the effect of the electrospinning conditions on fiber dimension. The addition of a small amount of h-PEO to l-PEO was responsible for a significant increase in fiber mechanical resistance, without affecting the nano-scale fiber size. Moreover, the mixing of h-PEO and l-PEO improved the interaction with ALG, resulting in an increase in chain entanglement degree that is functional in the electrospinning process.

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Mechanical properties and dynamics of degradation of polylactide matrix composites with calcium and sodium alginate fibers

Journal of Composite Materials ◽

10.1177/0021998313477897 ◽

2013 ◽

Vol 48 (7) ◽

pp. 815-824 ◽

Cited By ~ 1

Author(s):

Magdalena Bartkowiak-Jowsa ◽

Anna Kwiatkowska ◽

Romuald Będziński ◽

Celina Pezowicz ◽

Jarosław Filipiak ◽

...

Keyword(s):

Mechanical Properties ◽

Sodium Alginate ◽

Matrix Composites ◽

Alginate Fibers

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Shape-Controlled Production of Biodegradable Calcium Alginate Gel Microparticles Using a Novel Microfluidic Device

Langmuir ◽

10.1021/la061729+ ◽

2006 ◽

Vol 22 (22) ◽

pp. 9453-9457 ◽

Cited By ~ 151

Author(s):

Kan Liu ◽

Hui-Jiang Ding ◽

Jing Liu ◽

Yong Chen ◽

Xing-Zhong Zhao

Keyword(s):

Microfluidic Device ◽

Calcium Alginate ◽

Alginate Gel ◽

Calcium Alginate Gel ◽

Shape Controlled

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Characterization of Hydrophilic Membranes Based on PVP and Carboxymetylcelulose Staple Fibers Infused with Calcium Alginate

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.312-315.513 ◽

2011 ◽

Vol 312-315 ◽

pp. 513-517

Author(s):

Leila Figueiredo de Miranda ◽

Mauro Cesar Terence ◽

Isabella Tereza Ferro Barbosa ◽

Ingrid Martins Rubin ◽

Jefferson Fernandes Alves

Keyword(s):

Mechanical Properties ◽

Electron Beam ◽

Ionizing Radiation ◽

Carboxymethyl Cellulose ◽

Calcium Alginate ◽

Gel Fraction ◽

Lesion Type ◽

Hydrophilic Membranes ◽

Hydrophilic Membrane

Hydrophilic membranes based on PVP, containing 0.4 and 1% of carboxymethylcellulose staple fibers infused with calcium alginate were obtained and characterized in this study. The main proposal of this study is related to hydrogels based on PVP modified with carboxymethyl cellulose staple fibers infused with calcium alginate. This modified hydrogel is a hydrophilic membrane with better mechanical properties that can incorporate adequate drugs into the fibers for each lesion type. The hydrogels were obtained using ionizing radiation with an electron beam, at a dose of 25 kGy. The membrane’s characterization was performed by tensile and physic-chemical tests (gel fraction and swelling). The results obtained showed that the membranes have higher mechanical strength, a higher swelling degree and a lower gel fraction.

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