PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7645

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  • Article
    Citation - WoS: 61
    Citation - Scopus: 64
    Electrospun Gelma Fibers and P(hema) Matrix Composite for Corneal Tissue Engineering
    (Elsevier Ltd., 2021) Arıca, Tuğçe A.; Güzelgülgen, Meltem; Yıldız, Ahu Arslan; Demir, Mustafa Muammer
    The development of biocompatible and transparent three-dimensional materials is desirable for corneal tissue engineering. Inspired from the cornea structure, gelatin methacryloyl-poly(2-hydroxymethyl methacrylate) (GelMA-p(HEMA)) composite hydrogel was fabricated. GelMA fibers were produced via electrospinning and covered with a thin layer of p(HEMA) in the presence of N,N?-methylenebisacrylamide (MBA) as cross-linker by drop-casting. The structure of resulting GelMA-p(HEMA) composite was characterized by spectrophotometry, microscopy, and swelling studies. Biocompatibility and biological properties of the both p(HEMA) and GelMA-p(HEMA) composite have been investigated by 3D cell culture, red blood cell hemolysis, and protein adsorption studies (i.e., human serum albumin, human immunoglobulin and egg white lysozyme). The optical transmittance of the GelMA-p(HEMA) composite was found to be approximately 70% at 550 nm. The GelMA-p(HEMA) composite was biocompatible with tear fluid proteins and convenient for cell adhesion and growth. Thus, as prepared hydrogel composite may find extensive applications in future for the development of corneal tissue engineering as well as preparation of stroma of the corneal material. © 2020 Elsevier B.V.
  • Article
    Citation - WoS: 11
    Citation - Scopus: 11
    Effect of Alkali Metal Hydroxides on the Morphological Development and Optical Properties of Ceria Nanocubes Under Hydrothermal Conditions
    (American Scientific Publishers, 2011) Kepenekçi, Özlem; Eanes, Mehtap; Demir, Mustafa Mustafa
    Nanocrystalline cerium(IV) oxide (CeO2, ceriaceria) particles were produced via the hydrothermal treatment of cerium nitrate hexahydrate with various alkali metal hydroxides (MOH: M = Li, Na, K). Experimental conditions such as [MOH], reaction temperature, and reaction time were studied. Particle morphology as well as size of crystallites was precisely controlled by choice of experimental conditions. While rod-shaped particles were obtained at 120 C, well-defined nanocubes were formed at higher temperatures regardless of the choice of MOH. Examination of particle growth kinetics, in the final stages of crystallization, showed that particle growth rate is controlled by two different mechanisms. Grain boundary diffusion controls the particle growth in the presence of NaOH with an activation energy of 113.8 kj/mol and surface diffusion for LiOH ad KOH with the activation energy of 43.0–150.9 kj/mol, respectively. In addition, the particles exhibit strong violet and blue emissions at 400 nm and 370 nm. The former emission originates from excitation of a wide band gap of CeO2. The latter one is attributed to the trivalency of the cerium ion and appears to be sensitive to all the experimental conditions studied. Both extending reaction time and increasing temperature reduce the intensity of the 370 nm emission and increase the intensity of the 400 nm emission.