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1.
001-es BibID:
BIBFORM116532
035-os BibID:
(WoS)001070439900001 (Scopus)85169291237 (cikkazonosító)105702
Első szerző:
Benea, Ioana Cristina
Cím:
Biocatalytic synthesis of new polyesteramides from ?-caprolactam and hydroxy acids: Structural characterization, biodegradability, and suitability as drug nanocarriers / Ioana Cristina Benea, Izolda Kántor, Anamaria Todea, Alessandro Pellis, Ioan Bîtcan, Lajos Nagy, Sandor Kéki, Diana Maria Dreavā, Francisc Péter, Tivadar Feczkó
Dátum:
2023
ISSN:
1381-5148
Megjegyzések:
The synthesis of polyesters and polyamides by enzyme-catalyzed processes in vitro was developed in the last decades as a green alternative to obtain biodegradable synthetic polymers with various applications, such as nanoparticle-sized carriers for drug delivery. Polyesteramides were much less studied in this respect, although having the presumable advantage of increased mechanical and thermic resistance brought by the amide moieties. In this work, polyesteramides were synthesized for the first time employing as raw materials epsilon-caprolactam and a hydroxy acid. L-malic, 3-hydroxybutyric, 12-hydroxystearic and 16-hydroxyhexadecanoic acid, respectively, were investigated as co-monomers in solventless or organic medium, using the immobilized lipase Novozyme 435 as catalyst. The short chain hydroxy acids holding secondary hydroxyl groups yielded oligomers with average degree of polymerization no higher than 4, while in the case of the long-chain 12-hydroxystearic acid this value increased to 7. The best results were achieved by using 16-hydroxyhexadecanoic acid in 2:1 M excess at 80. C, yielding a product with 75% copolymer content and average molecular weight higher than 3000 Da. The emulsion-solvent evaporation method allowed the efficient production of nanoparticles based on this copolymer, with sizes around 230 nm, used for the encapsulation of a model bioactive compound, the anticancer drug sorafenib. Production yields of >70% and encapsulation efficiencies of around 60% are very promising for further development of this approach.
Tárgyszavak:
Természettudományok
Kémiai tudományok
idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Polyesteramide
Biocatalysis
Lipase
Polymer nanoparticle
Encapsulation
Megjelenés:
Reactive & Functional Polymers. - 191 (2023), p. 1-17. -
További szerzők:
Kántor Izolda
Todea, Anamaria
Pellis, Alessandro
Bîtcan, Ioan
Nagy Lajos (1979-) (vegyész)
Kéki Sándor (1964-) (polimer kémikus)
Dreava, Diana-Maria
Péter, Francisc
Feczkó Tivadar
Pályázati támogatás:
TKP2021-EGA-20
Egyéb
Internet cím:
Szerző által megadott URL
DOI
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2.
001-es BibID:
BIBFORM103963
035-os BibID:
(WOS)000522021900002 (Scopus)85082415468
Első szerző:
Todea, Anamaria
Cím:
Thermal behavior of oligo[(epsilon-caprolactone)-co-delta-gluconolactone] enzymatically synthesized in reaction conditions optimized by experimental design / Anamaria Todea, Diana Aparaschivei, Ioan Bîtcan, Ionuț Valentin Ledeți, Geza Bandur, Francisc Péter, Lajos Nagy, Sándor Kéki, Emese Biró
Dátum:
2020
ISSN:
1388-6150 1588-2926
Megjegyzések:
The thermal behavior of co-oligomers of epsilon-caprolactone (ECL) with gluconolactone, compared to the epsilon-caprolactone oligomer, has been assessed by thermogravimetric analysis, while differential scanning calorimetry was used to evaluate the melting comportment. As the insertion of more hydrophilic structural units can improve the properties and functionalities of the ECL oligoesters, the enzymatic in vitro oligomerization process was optimized by a 3-factorial/3-level experimental design, using the Box-Behnken method. The selected independent variables were the temperature, the enzyme amount, and the molar ratio of monomers, while the co-oligomerization degree and the mass average molecular mass (calculated from MALDI-TOF MS data) were the response variables. The results indicate that temperature has the most significant effect and is directly correlated with the formation of linear co-oligoesters. The overall effect of the other variables was also significant. The thermogravimetric analysis of the co-oligomer synthesized in the optimized conditions indicated a decrease of the thermal stability and compared to the ECL oligomer. Thermoanalytical techniques can consistently improve the utilization efficiency of polymer-based formulations in pharmaceutical and medical applications.
Tárgyszavak:
Természettudományok
Kémiai tudományok
idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Biocatalysis
Enzymatic oligomerization
Thermal analysis
Lipaseepsilon-caprolactone
delta-gluconolactone
Megjelenés:
Journal of Thermal Analysis and Calorimetry. - 141 : 3 (2020), p. 1017-1026. -
További szerzők:
Aparaschivei, Diana
Bîtcan, Ioan
Ledeți, Ionuț Valentin
Bandur, Geza
Péter, Francisc
Nagy Lajos (1979-) (vegyész)
Kéki Sándor (1964-) (polimer kémikus)
Biro, Emese
Internet cím:
Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
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Saját polcon:
3.
001-es BibID:
BIBFORM104069
035-os BibID:
(WoS)000489104300028 (Scopus)85071906261 (cikkazonosító)1402
Első szerző:
Todea, Annamaria
Cím:
Biodegradable Oligoesters of epsilon-Caprolactone and 5-Hydroxymethyl-2-Furancarboxylic Acid Synthesized by Immobilized Lipases / Anamaria Todea, Ioan Bîtcan, Diana Aparaschivei, Iulia Păuşescu, Valentin Badea, Francisc Péter, Vasile Daniel Gherman, Gerlinde Rusu, Lajos Nagy, Sándor Kéki
Dátum:
2019
ISSN:
2073-4360
Megjegyzések:
Following the latest developments, bio-based polyesters, obtained from renewable raw materials, mainly carbohydrates, can be competitive for the fossil-based equivalents in various industries. In particular, the furan containing monomers are valuable alternatives for the synthesis of various new biomaterials, applicable in food additive, pharmaceutical and medical field. The utilization of lipases as biocatalysts for the synthesis of such polymeric compounds can overcome the disadvantages of high temperatures and metal catalysts, used by the chemical route. In this work, the enzymatic synthesis of new copolymers of ?-caprolactone and 5-hydroxymethyl-2-furancarboxylic acid has been investigated, using commercially available immobilized lipases from Candida antarctica B. The reactions were carried out in solvent-less systems, at temperatures up to 80 C. The structural analysis by MALDI TOF-MS, NMR, and FT-IR spectroscopy confirmed the formation of cyclic and linear oligoesters, with maximal polymerization degree of 24 and narrow molecular weight distribution (dispersity about 1.1). The operational stability of the biocatalyst was explored during several reuses, while thermal analysis (TG and DSC) indicated a lower thermal stability and higher melting point of the new products, compared to the poly(epsilon-caprolactone) homopolymer. The presence of the heterocyclic structure in the polymeric chain has promoted both the lipase-catalyzed degradation and the microbial degradation. Although, poly(epsilon-caprolactone) is a valuable biocompatible polymer with important therapeutic applications, some drawbacks such as low hydrophilicity, low melting point, and relatively slow biodegradability impeded its extensive utilization. In this regard the newly synthesized furan-based oligoesters could represent a "green" improvement route.
Tárgyszavak:
Természettudományok
Kémiai tudományok
idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
copolymerization
renewable
oligoester
lipase
furan-based
epsilon-caprolactone
Megjelenés:
Polymers. - 11 : 9 (2019), p. 1-17. -
További szerzők:
Bîtcan, Ioan
Aparaschivei, Diana
Pausescu, Iulia
Badea, Valentin
Francisc Péter
Gherman, Vasile Daniel
Rusu, Gerlinde
Nagy Lajos (1979-) (vegyész)
Kéki Sándor (1964-) (polimer kémikus)
Pályázati támogatás:
GINOP-2.3.3-15-2016-00021
GINOP
Internet cím:
DOI
Intézményi repozitóriumban (DEA) tárolt változat
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