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001-es BibID:	BIBFORM083490
035-os BibID:	(WoS)000518870200012 (Scopus)85078760943
Első szerző:	Kéri Mónika (környezetkutató vegyész)
Cím:	Gelatin content governs hydration induced structural changes in silica-gelatin hybrid aerogels : implications in drug delivery / Mónika Kéri, Attila Forgács, Vanda Papp, István Bányai, Péter Veres, Adél Len, Zoltán Dudás, István Fábián, József Kalmár
Dátum:	2020
ISSN:	1742-7061
Megjegyzések:	Silica-gelatin hybrid aerogels of varying gelatin content (from 4 wt.% to 24 wt.%) can be conveniently impregnated with hydrophobic active agents (e.g. ibuprofen, ketoprofen) in supercritical CO2 and used as drug delivery systems. Contrast variation neutron scattering (SANS) experiments show the molecular level hybridization of the silica and the gelatin components of the aerogel carriers. The active agents are amorphous, and homogeneously dispersed in these porous, hybrid matrices. Importantly, both fast and retarded drug release can be achieved with silica-gelatin hybrid aerogels, and the kinetics of drug release is governed by the gelatin content of the carrier. In this paper, for the first time, a molecular level explanation is given for the strong correlation between the composition and the functionality of a family of aerogel based drug delivery systems. Characterization of the wet aerogels by SANS and by NMR diffusiometry, cryoporometry and relaxometry revealed that the different hydration mechanisms of the aerogels are responsible for the broad spectrum of release kinetics. Low-gelatin (4-11 wt.%) aerogels retain their open-porous structure in water, thus rapid matrix erosion dictates fast drug release from these carriers. In contrast to this, wet aerogels of high gelatin content (18-24 wt.%) show well pronounced hydrogel-like characteristics, and a wide gradual transition zone forms in the solid-liquid interface. The extensive swelling of the high-gelatin hybrid backbone results in the collapse of the open porous structure, that limits mass transport towards the release medium, resulting in slower, diffusion controlled drug release.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk
Megjelenés:	Acta Biomaterialia. - 105 (2020), p. 131-145. -
További szerzők:	Forgács Attila (1988-) (vegyész) Papp Vanda (1996-) (vegyész, biomérnök) Bányai István (1953-) (vegyész) Veres Péter (1991-) (vegyész) Len Adél Dudás Zoltán Fábián István (1956-) (vegyész) Kalmár József (1985-) (vegyész)
Pályázati támogatás:	ÚNKP-19-4 egyéb OTKA FK 17-124571 OTKA GINOP-2.3.2-15-2016-00008 GINOP
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001-es BibID:	BIBFORM130227
035-os BibID:	(WoS)001494626500001 (Scopus)105005889421
Első szerző:	Papp Vanda (vegyész, biomérnök)
Cím:	Structure and Swelling Properties of Biodegradable Cross-Linked Polyurethanes by Means of Nuclear Magnetic Resonance / Papp, Vanda; Vadkerti, Bence; Bányai, István; Kéki, Sándor; Kéri, Mónika
Dátum:	2025
ISSN:	1520-6106
Megjegyzések:	In this study, the swelling properties and structural changes duringthe interaction with liquid media of biodegradable cross-linked polyurethanespromising from medical and environmental points of view are reported. Tocharacterize the polyurethane samples, containing sucrose as cross-linking agentin different concentrations, in the dry state, and swollen in water and dimethylsulfoxide (DMSO), low- and high-field liquid-phase NMR spectroscopicmethods, such as relaxometry, diffusometry, and cryoporometry, were applied.Based on the NMR relaxation features of the swelling liquids and the swollencross-linked polymers, the difference in the interaction with the two liquids wasevaluated; furthermore, the rigid and mobile domains in the amorphous part ofthe polymer were successfully identified. The change of their ratio with thesucrose content and the restricted diffusion of DMSO in the swollen polymernetwork reflected the cross-link density and highlighted the role of dangling chains. The swelling process in DMSO was followed bythe change of the T2 relaxation of the infiltrating liquid in time and was described by the second-order kinetic model with asuggested, detailed swelling mechanism. Cryoporometry measurements enlightened the effect of swelling on the size change of theliquid domains in the cross-linked structure.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk polyurethane crosslinked structure NMR spectroscopy swelling process
Megjelenés:	Journal Of Physical Chemistry B. - 129 : 22 (2025), p. 5607-5620. -
További szerzők:	Vadkerti Bence (1994-) (okleveles vegyészmérnök) Bányai István (1953-) (vegyész) Kéki Sándor (1964-) (polimer kémikus) Kéri Mónika (1984-) (környezetkutató vegyész)
Pályázati támogatás:	147503 OTKA 131989 OTKA 135169 OTKA 138823 OTKA KDP-2021 Egyéb DETKA Egyéb Bolyai János Kutatási Ösztöndíj - MTA Egyéb Nemzeti Kutatási, Fejlesztési és Innovációs Alap, TKP2021-EGA-20 Egyéb
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001-es BibID:	BIBFORM113891
035-os BibID:	(WoS)001053307800001 (Scopus)85166955717
Első szerző:	Papp Vanda (vegyész, biomérnök)
Cím:	State and role of water confined in cement and composites modified with metakaolin and additives / Vanda Papp, Róbert Janovics, Tamás Péter Kertész, Zoltán Nemes, Tamás Fodor, István Bányai, Mónika Kéri
Dátum:	2023
ISSN:	0167-7322
Megjegyzések:	Cement as a porous material contains pores and cracks on the whole nanoscale forming an interconnected pore structure. Its interaction with water during the rehydration of cement plays a key role in every application, such as in nuclear waste treatment, where cement binders are commonly used for conditioning liquid radioactive waste. In the prediction of the long-term disposal the knowledge of water mobility and distribution in the formed porous cement matrix is essential. In this study we systematically investigate the effects of metakaolin and several components of the liquid phase (complexing agents, model ions, boric acid, etc.) on the hydrated solid structure by various nuclear magnetic resonance (NMR) methods. The novelty lies in the complex use of such non-conventional techniques that separately provide only partial information of the cement structure; however, the gained results complete each other to offer a new approach in the structural study under several conditions. Water mobility is deduced from NMR T2 relaxation distributions and D2O-H2O exchange diffusion measurements, and the conclusion on structural properties is supported by the macropore structure revealed from NMR cryoporometry and SEM (scanning electron microscopy) images, as well as by following the formation of pores and water domains in the curing process with NMR relaxometry. The results confirm that metakaolin was built into the CSH (calcium silicate hydrate) gel region without altering its mesoporous structure, however, it significantly decreased the capillary pore size and the diffusion coefficient of water. Complexing agent concentration between 2 and 20 g/l and the presence of model ions did not cause significant structural changes, while the rehydration decreased the size of capillary pores due to swelling.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk
Megjelenés:	Journal Of Molecular Liquids. - 388 (2023), p. 1-10. -
További szerzők:	Janovics Róbert (1984-) (környezetkutató) Kertész Tamás Péter (2001-) (egyetemi hallgató) Nemes Zoltán (1976-) Fodor Tamás (1987-) (vegyész) Bányai István (1953-) (vegyész) Kéri Mónika (1984-) (környezetkutató vegyész)
Pályázati támogatás:	OTKA-135169 OTKA OTKA-131989 OTKA KDP-2021 Egyéb GINOP-2.3.4-15-2020-00007 GINOP 2019-2.1.7-ERA-NET-2021-00021 Egyéb
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