CCL

Összesen 2 találat.
#/oldal:
Részletezés:
Rendezés:

1.

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
Internet cím:Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:

2.

001-es BibID:BIBFORM113891
035-os BibID:(cikkazonosító)122716 (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
Internet cím:Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Rekordok letöltése1