Makale KoleksiyonuArticle Collecitonhttps://hdl.handle.net/11491/33132024-03-26T20:02:40Z2024-03-26T20:02:40ZPhotocrosslinked methacrylated pectin and methacrylated hyaluronic acıd wound dressing loaded with oleuropein as bioactive agentMoran Bozer, BüşraÖzkahraman, BengiMert Balaban, Hümeyrahttps://hdl.handle.net/11491/87752024-02-01T07:04:52Z2023-01-01T00:00:00ZPhotocrosslinked methacrylated pectin and methacrylated hyaluronic acıd wound dressing loaded with oleuropein as bioactive agent
Moran Bozer, Büşra; Özkahraman, Bengi; Mert Balaban, Hümeyra
Oleuropein-loaded photocrosslinked hydrogels, consisting of methacrylated pectin (PEC-MA) andmethacrylated hyaluronic acid (HA-MA), were developed as a new hydrogel wound dressing.Pectin and hyaluronic acid were methacrylated and the composite hydrogels were developed byphotocrosslinking of the methacrylated polymer precursors. Methacrylation and the photocros-slinking reactions were approved by1H-NMR and FTIR analyses. In addition to thermal and mor-phological characterizations, swelling andin vitrodegradation studies were performed. Moreimportantly, bioactivity studies, such as cytotoxicity, genotoxicity and hemolysis were performedto reveal the potential of the oleuropein-loaded photocrosslinked hybrid hydrogels for wounddressing applications.In vitroscratch assay studies showed that oleuropein-loaded wound dressingeffectively promoted the wound healing compared to the control in 24 hrs. Oleuropein-loadedphotocrosslinked hydrogels had no genotoxic and cytotoxic effects on L929 cells and could havea potential for wound healing applications.
2023-01-01T00:00:00ZAdsorptive separation of CH4, H2, CO2, and N2 using fullerene pillared graphene nanocomposites: Insights from molecular simulationsMert Balaban, HümeyraDeniz, Celal UtkuBaykasoğlu, Cengizhttps://hdl.handle.net/11491/87282024-01-24T06:55:50Z2023-01-01T00:00:00ZAdsorptive separation of CH4, H2, CO2, and N2 using fullerene pillared graphene nanocomposites: Insights from molecular simulations
Mert Balaban, Hümeyra; Deniz, Celal Utku; Baykasoğlu, Cengiz
Context The adsorptive separation performances of fullerene pillared graphene nanocomposites (FPGNs) with tunable micro and meso porous morphology are investigated for the binary mixtures of CH4, H2, CO2 and N2 by using grand canonical Monte Carlo (GCMC) simulations. Diferent fullerene types are considered in designs as pillar to investigate the efects of porosity on the gas separation performances of FPGNs, and the GCMC simulations are performed for an equimolar binary mixture of CO2/H2, CO2/CH4, CO2/N2 and CH4/H2 inspired by industrial gas mixtures. It is found that CO2/N2, CO2/H2 and CH4/H2 selectivity of FPGNs are about 72, 410 and 145 at 298 K and 1 bar, which are higher than those for several adsorbent materials reported. Methods Five diferent FPGN models which contain covalently bonded periodical fullerene and graphene units were constructed using C60, C180, C320, C540 and C720 fullerenes, followed by geometry optimization using Open Babel. All GCMC simulations of adsorption were performed in the RASPA. The adsorption isotherms of FPGNs for pure gases are comparatively examined, and their performances are discussed based on the pore structure and isosteric heat of adsorption. Then, the separation factors of FPGNs for equimolar binary mixtures of these gases are elucidated from the diference in the heat of adsorption and the adsorption selectivity
2023-01-01T00:00:00ZThiolated Cellulose: A Dual-Acting Mucoadhesive and Permeation-Enhancing PolymerKali, GergelyÖzkahraman, BengiLaffleur, FlaviaKnoll, PatrickWibel, RichardZoller, KatrinBernkop-Schnurch, Andreashttps://hdl.handle.net/11491/87142023-11-28T07:57:37Z2023-01-01T00:00:00ZThiolated Cellulose: A Dual-Acting Mucoadhesive and Permeation-Enhancing Polymer
Kali, Gergely; Özkahraman, Bengi; Laffleur, Flavia; Knoll, Patrick; Wibel, Richard; Zoller, Katrin; Bernkop-Schnurch, Andreas
This study aims to design an anionic, thiolated cellulose derivative and to evaluate its mucoadhesive and permeation-enhancing properties utilizing enoxaparin as a model drug. 2-Mercaptosuccinic acid-modified cellulose (cellulose–mercaptosuccinate) was synthesized by the reaction of cellulose with S-acetylmercaptosuccinic anhydride. The chemical structure of the target compound was confirmed by FTIR and 1H NMR spectroscopy. The thiol content was determined by Ellman’s test. The conjugate exhibited 215.5 ± 25 μmol/g of thiol groups and 84 ± 16 μmol/g of disulfide bonds. Because of thiolation, mucoadhesion on porcine intestinal mucosa was 9.6-fold enhanced. The apparent permeability (Papp) of the model dye Lucifer yellow was up to 2.2-fold improved by 0.5% cellulose–mercaptosuccinate on a Caco-2 cell monolayer. Enoxaparin permeation through rat intestinal mucosa increased 2.4-fold in the presence of 0.5% cellulose–mercaptosuccinate compared with the drug in buffer only. In vivo studies in rats showed an oral bioavailability of 8.98% using cellulose–mercaptosuccinate, which was 12.5-fold higher than that of the aqueous solution of the drug. Results of this study show that the modification of cellulose with 2-mercaptosuccinic acid provides mucoadhesive and permeation-enhancing properties, making this thiolated polymer an attractive excipient for oral drug delivery.
2023-01-01T00:00:00ZHydrophobic surface modification and characterization of melamine foamOkutan, MerveBoran, FilizErgün, AyçaKanca, YusufÖzkahraman, BengiDeligöz, Hüseyinhttps://hdl.handle.net/11491/87092023-11-27T06:27:37Z2023-01-01T00:00:00ZHydrophobic surface modification and characterization of melamine foam
Okutan, Merve; Boran, Filiz; Ergün, Ayça; Kanca, Yusuf; Özkahraman, Bengi; Deligöz, Hüseyin
Abstract: Superhydrophobic and oleophilic modification of commercial acoustic melamine foam (MF) was made in this study. The modification was carried out with chitosan (CHI) and silica particles (SiO2 ), by using both a layer-by-layer-like approach (LbL) and dip coating technique. Subsequently, 1-octadecanethiol was used as a secondary modification agent. QCM-D, SEM, and FTIR analyses confirmed that the coating was successfully performed. After the modification, the column wall thicknesses increased than that of MF and they ranged from 25% to 48% for modified MF with an LbL-like approach (MMF) and modified MF via dip coating technique (MMFd), respectively. The sorption experiments showed that modified MFs, which had a water contact angle (WCA) above 160°, could sorb several model pollutants (vegetable oil, chloroform, ethanol, and toluene) up to 76–130 times their original weight. It had been determined that MMF protects its open-pore structure better than that of MMFd, which indicated that MF has a more uniform pore structure after modification. Furthermore, after 10 cycles of the sorption and release process, there was no significant change in sorption capacity, and they preserved their mechanical stability and flexibility
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