Polysulfon Alginate matrix Bacteria

2016 ◽  
pp. 70-78
Keyword(s):  
Author(s):  
Rosetânia Correia Neves da Conceição ◽  
Rayssa Dias Batista ◽  
Fernanda Munhoz dos Anjos Leal Zimmer ◽  
Ianna Kelly Martins Trindade ◽  
Alex Fernando de Almeida ◽  
...  

Author(s):  
Dariusz Kulus ◽  
Alicja Tymoszuk

AbstractThe popularity of nanoparticles (NPs) is continuously increasing. To date, however, there has been little research on the application of NPs in plant cryopreservation, i.e. storage of tissues in liquid nitrogen (LN). The aim of this study is to analyze the effect and evaluate the usefulness of gold nanoparticles (AuNPs) in regard to cryobiology studies. In vitro-derived shoot tips of Lamprocapnos spectabilis ‘Valentine’ were cryopreserved with the encapsulation-vitrification protocol. Gold nanoparticles (at 10–30 ppm concentration; 13 nm in size) were added either into the preculture medium; to the protective bead matrix during encapsulation; or to the recovery medium after rewarming of samples. The control plants were produced from cryopreserved explants non-treated with nanoparticles or treated with colloid dispersion medium without NPs. A non-LN-treated standard was also considered. The influence of AuNPs on the cryopreservation efficiency was determined by evaluating the recovery rate of explants and their morphogenic response; the membrane stability index (MSI); the concentration of pigments in shoots; and the antioxidant enzymes activity. The genetic stability of the plant material was evaluated using Start Codon Targeted Polymorphism (SCoT) markers. It was found that 10 ppm of AuNPs added into the alginate bead matrix improved the recovery level of LN-derived shoot tips (70.0%) compared to the non-NPs-treated cryopreserved control (50.5%). On the other hand, the presence of nanoparticles in the recovery medium had a deleterious effect on the survival of explants. AuNPs usually had no impact on the MSI (73.9–85.9%), except for those added into the recovery medium at the concentration of 30 ppm (decline to 55.8%). All LN-derived shoots were shorter and contained less chlorophyll and carotenoids than the untreated standard. Moreover, the application of AuNPs affected the enzymatic activity in L. spectabilis. Minor genetic variation was found in 8.6% of plants if AuNPs were added either into the preculture medium (at 10 and 20 ppm) or to the alginate matrix (at 30 ppm). In conclusion, AuNPs added at a lower concentration (10 ppm) into the protective bead matrix can significantly improve the cryopreservation efficiency in L. spectabilis with no alternation in the DNA sequence.


Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 830
Author(s):  
Sina Rößler ◽  
Andreas Brückner ◽  
Iris Kruppke ◽  
Hans-Peter Wiesmann ◽  
Thomas Hanke ◽  
...  

Today, materials designed for bone regeneration are requested to be degradable and resorbable, bioactive, porous, and osteoconductive, as well as to be an active player in the bone-remodeling process. Multiphasic silica/collagen Xerogels were shown, earlier, to meet these requirements. The aim of the present study was to use these excellent material properties of silica/collagen Xerogels and to process them by additive manufacturing, in this case 3D plotting, to generate implants matching patient specific shapes of fractures or lesions. The concept is to have Xerogel granules as active major components embedded, to a large proportion, in a matrix that binds the granules in the scaffold. By using viscoelastic alginate as matrix, pastes of Xerogel granules were processed via 3D plotting. Moreover, alginate concentration was shown to be the key to a high content of irregularly shaped Xerogel granules embedded in a minimum of matrix phase. Both the alginate matrix and Xerogel granules were also shown to influence viscoelastic behavior of the paste, as well as the dimensionally stability of the scaffolds. In conclusion, 3D plotting of Xerogel granules was successfully established by using viscoelastic properties of alginate as matrix phase.


2020 ◽  
Vol 7 (12) ◽  
pp. 3888-3900 ◽  
Author(s):  
I. Vassalini ◽  
G. Ribaudo ◽  
A. Gianoncelli ◽  
M. F. Casula ◽  
I. Alessandri

β-Cyclodextrin-functionalized silver nanoparticles were embedded within an alginate matrix to obtain hydrogels that capture, detect and remove organic pollutants from water.


2017 ◽  
Vol 262 ◽  
pp. 103-106 ◽  
Author(s):  
John Kwame Bediako ◽  
Myung Hee Song ◽  
Yeoung Sang Yun

High-capacity polyethylenimine (PEI)/Ca-alginate blended hydrogel fibers were fabricated via three steps, viz. electrostatic blending of PEI and alginate, ionotropic gelation of alginate and CaCl2, and fixing of PEI into the Ca-alginate matrix, using glutaraldehyde (GA) as a crosslinker. Two crosslinking approaches resulted in different stabilities and gold uptake capacities of the prepared sorbents. Post-crosslinking approach was more efficient than pre-crosslinking likely owing to the better crosslinking efficiency, leading to better stability and sorption capacity. Furthermore, X-ray diffraction (XRD) study revealed the reduction of Au (III) to metallic gold, Au (0) in the crosslinked fibers. The Au (0) predominancy was confirmed with a metal desorption study. The present study thus demonstrates the possibility of recovering metallic gold from aqueous solutions by direct adsorption-coupled-reduction approach using GA-crosslinked PEI/Ca-alginate fibers.


1999 ◽  
Vol 65 (5) ◽  
pp. 2025-2031 ◽  
Author(s):  
Mohamed O. Elasri ◽  
Robert V. Miller

ABSTRACT We have developed a bioluminescent whole-cell biosensor that can be incorporated into biofilm ecosystems. RM4440 is a Pseudomonas aeruginosa FRD1 derivative that carries a plasmid-basedrecA-luxCDABE fusion. We immobilized RM4440 in an alginate matrix to simulate a biofilm, and we studied its response to UV radiation damage. The biofilm showed a protective property by physical shielding against UV C, UV B, and UV A. Absorption of UV light by the alginate matrix translated into a higher survival rate than observed with planktonic cells at similar input fluences. UV A was shown to be effectively blocked by the biofilm matrix and to have no detectable effects on cells contained in the biofilm. However, in the presence of photosensitizers (i.e., psoralen), UV A was effective in inducing light production and cell death. RM4440 has proved to be a useful tool to study microbial communities in a noninvasive manner.


2017 ◽  
Vol 39 (5) ◽  
Author(s):  
JÚLIO CÉSAR GOMES PEREIRA ◽  
SELMA SILVA ROCHA ◽  
LUCIANA CARDOSO NOGUEIRA LONDE ◽  
MARCELA CAROLINE BATISTA DA MOTA ◽  
PABLO FERNANDO SANTOS ALVES ◽  
...  

ABSTRACT The banana crop stands out as an activity of great social and economic importance in Brazil, which occupies the fifth place in world production. Synthetic seed production is becoming promising for a micropropagation and in vitro conservation. The aim of the study was to analyze the conversion and growth of ‘Prata-anã’ banana’s microshoots clone Gorutuba from synthetic seed in MS medium and vermiculite, different substrates and concentrations of BAP (6-benzylaminopurine) associated with ANA (acetic naphthalene acid) in the constitution of its capsule were tested. The microshoots were immersed in the sodium alginate matrix (3%) and dripped in a solution of CaCl2.2H2O (100 mM) for complexation and then in KNO3 solution (100 mM) to decomplex. The experimental design was completely randomized in a 2 x 5 factorial design (substrate x BAP concentrations), containing different substrates (MS culture medium and vermiculite) and BAP concentrations (2.22, 4.44, 6.66, 8.88 and 13.32 µmol L-1) associated with NAA (naphthalene acetic acid) 0.54 µmol L-1, totaling 10 treatments, with 4 replicates, and that each replicate containing 5 seeds. The evaluations of conversion, number of leaves, leaf length, leaf height, number of roots, root length and oxidation were performed at 30 and 60 days.The use of the MS medium provided better growth results in relation to vermiculite as substrate, in which the different BAP concentrations did not differ from each other. It was found that, in MS culture medium, BAP concentrations above 8.88 µmol L-1 in the capsule composition are not indicated for microshoots growth.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Ana Sofia Pais ◽  
Sandra Reis ◽  
Mafalda Laranjo ◽  
Francisco Caramelo ◽  
Fátima Silva ◽  
...  

Abstract Background Cryopreservation of ovarian tissue is a powerful technique for preserving female fertility, as it can restore fertility and endocrine function. To increase the longevity of the transplant and decrease the risk of reimplantation of neoplastic cells, several studies have been carried out with culture of ovarian tissue. The aim of this study was to compare a conventional (2D) culture with an alginate matrix three-dimensional (3D) model for ovarian tissue culture. Results The ovarian tissue culture within the alginate matrix (3D) was similar to 2D culture, regarding follicular density and cell apoptosis in follicles and stroma. The proliferation rate remained stable in both models for follicles, but for stromal cell proliferation it decreased only in 3D culture (p = 0.001). At 24 h of culture, cytotoxicity was lower in the 3D model (p = 0.006). As culture time increased, cytotoxicity seemed similar. Degradation of the tissue was suggested by the histological score analysis of tissue morphology after 72 h of culture. Tissue injury was greater (p = 0.01) in 3D culture due to higher interstitial oedema (p = 0.017) and tissue necrosis (p = 0.035). Conclusion According to our results, 3D culture of ovarian tissue has no advantage over 2Dculture; it is more time consuming and difficult to perform and has worse reproducibility.


2022 ◽  
pp. 131652
Author(s):  
M. Infanta Diana ◽  
D. Lakshmi ◽  
P. Christopher Selvin ◽  
S. Selvasekarapandian

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