Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Design Strategies to Optimize Polymeric Vectors for mRNA Delivery(Taylor and Francis Ltd., 2025) Turhan, Z.Y.; Savaş, M.; Alakbarov, A.; Bulmus, V.mRNA holds great promise for preventing and treating a variety of diseases, from infectious diseases to diverse cancers, owing to its transient expression, lack of genomic integration, and scalable production. Among non-viral vectors, polymeric carriers are attractive due to their synthetic versatility and stability, which allow for precise tuning for efficient mRNA delivery. Their scalability further supports the applicability of polymeric vectors. Studies have addressed the room for improvement in polymeric systems for mRNA delivery and have adapted varying approaches depending on the type of polymeric structure, including but not limited to PEGylation, hydrophobic modification, and incorporation of responsive or targeting moieties. This review summarizes advances in polymeric vectors for mRNA delivery and highlights how distinct structural modifications influence toxicity, mRNA transfection efficiency, biodistribution, intracellular trafficking and immune activation, providing a framework for the rational design of next-generation polymeric vectors that can fully realize the clinical potential of mRNA therapeutics. © 2025 Taylor & Francis Group, LLC.Article Citation - WoS: 2Citation - Scopus: 2Hybrid Preceramic Aerogels for Oil and Solvent Cleanup(Wiley-v C H verlag Gmbh, 2025) Icin, Oyku; Vakifahmetoglu, CekdarThis study presents the first synthesis and characterization of monolithic hybrid preceramic aerogels using distinct drying techniques: ambient pressure (ambigels) and CO2 supercritical drying. Polymeric ambi/aerogels, derived from polyhydromethlysiloxane (PHMS) and divinylbenzene (DVB), are processed at 200 degrees C, while hybrid ceramic-polymer (ceramer) is produced through pyrolysis at 600 degrees C. Despite variations in drying methods, polymer and ceramer ambi/aerogels exhibit comparable microstructural characteristics, bulk density, pore size and volume, and specific surface area (542-841 m(2) g(-1)). Polymeric and ceramer ambigel with 90 vol% total porosity yield a compressive strength, reaching 2.5 MPa, demonstrating a low thermal conductivity of 0.046 W m-1 K-1. Sorption tests are conducted using oil and organic solvents in aqueous media to benefit their high hydrophobicity (112 degrees < theta < 142 degrees). Aerogels exhibit high sorption capacities: 13.17 g g(-1) for sesame oil, 11.74 g g(-1) for toluene, and 9.19 g g(-1) for n-hexane. The sorption rate for the oil is nearly 10 times slower than that for toluene and n-hexane. Regarding regeneration and reusability, polymer and ceramer aerogels show consistent sorption properties cycles tested for n-hexane and toluene.Article Citation - WoS: 1Citation - Scopus: 1Epoxy Matrix Nano Composites: Modulus, Strength and Ductility Enhancement Through Auxeticity of Α-Cristobalite Filler(Elsevier, 2023) Güden, Mustafa; Ülker, Sevkan; Movahedi, NimaThe negative Poisson's ratio (NPR) nano-size ?-Cristobalite particle/epoxy composites were prepared and tensile tested. The elastic modulus and strength of the composites were improved as the particle volume fraction increased from 0 to 0.02. Unlike the conventional particle reinforced composites, the fracture strain increased with the nano ?-Cristobalite addition, an effect which was ascribed to the intrinsic NPR behavior of the filler. © 2023 Elsevier B.V.Article Citation - WoS: 10Citation - Scopus: 12Transparent block copolymer thin films for protection of optical elements via chemical vapor deposition(Elsevier Ltd, 2018) Karabıyık, Merve; Ebil, ÖzgençIn this study, glycidyl methacrylate and 1H, 1H, 2H, 2H-perfluorodecyl acrylate copolymer p(GMA-co-PFDA) thin-films fabricated via Initiated Chemical Vapor Deposition (iCVD) were investigated as protective coatings on optical BK7 glass substrates and commercial optical filters. Durability tests based on military standards MIL-F-48616 and MIL-C-48497A were performed to evaluate performance of coatings for the protection of surfaces of optical elements. Cross-linked p(GMA-co-PFDA) copolymer coatings successfully passed all durability tests showing excellent mechanical properties and protection against humidity, salt water, swelling in water, and resistance to organic solvents while providing excellent adhesion to substrate. iCVD process enabled fine tuning of film morphology, mechanical properties and hydrophobicity by controlling the process parameters. Fabricated films were hydrophobic and highly transparent (>98%) in the wavelength range from 300 nm to 1000 nm. Optical transmittance measurements before and after coating process proved that while providing chemical and physical protection, p(GMA-co-PFDA) copolymer thin-films do not cause any detectable change in optical performance of commercial narrow band and wide band filters.Article Citation - WoS: 23Citation - Scopus: 27Novel Poss Reinforced Chitosan Composite Membranes for Guided Bone Tissue Regeneration(Springer Verlag, 2018) Tamburacı, Sedef; Tıhmınlıoğlu, FundaIn this study, novel composites membranes composed of chitosan matrix and polyhedral oligomeric silsesquioxanes (POSS) were fabricated by solvent casting method. The effect of POSS loading on the mechanical, morphological, chemical, thermal and surface properties, and cytocompatibility of composite membranes were investigated and observed by tensile test, atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), protein adsorption assay, air/water contact angle analysis and WST-1 respectively. Swelling studies were also performed by water absorption capacity determination. Results showed that incorporation of Octa-TMA POSS® nanofiller to the chitosan matrix increased the surface roughness, protein adsorption and swelling capacity of membranes. The addition of POSS enhanced significantly the ultimate tensile strength and strain at break of the composite membranes up to 3 wt% POSS loaded samples. An increase of about 76% in tensile strength and of strain at break 1.28% was achieved for 3 wt% POSS loaded nanocomposite membranes compared with chitosan membranes. The presence of POSS filler into polymer matrix increased the plasma protein adsorption on the surface. Maximum protein capacity and swelling was obtained for 10 wt% loaded samples. High cell viability results were obtained with indirect extraction of chitosan/POSS composites. Besides, cell proliferation and ALP activity results showed that POSS incorporation significantly increased the ALP activity of Saos-2 cells cultured on chitosan membranes. This novel composite membranes with tunable properties could be considered as a potential candidate for guided bone regeneration applicationsArticle Citation - WoS: 15Citation - Scopus: 21Triboluminescent Electrospun Mats With Blue-Green Emission Under Mechanical Force(American Chemical Society, 2017) İncel, Anıl; Varlıklı, Canan; McMillen, Colin D.; Demir, Mustafa MuammerFibrous mechanosensing elements can provide information about the direction of crack propagation and the mechanism of material failure when they are homogeneously dispersed into the bulk volume of materials. A fabrication strategy of fibrous systems showing triboluminescent (TL) responses is in high demand for such applications. In this work, micrometer-sized Cu(NCS)(py)2(PPh3) crystals were synthesized, and polymeric fibrous mats containing the TL crystals were obtained via electrospinning as a stress probe for the determination of mechanical impact. Four different polymeric systems have been employed (PMMA, PS, PU, and PVDF), and the mechano-optical sensing performance of electrospun mats of the polymer-crystal composites was measured. Photophysical properties (quantum yield, band gap, and broadness of the emission) of the TL crystal/electrospun mat composites were also studied. TL and PL emission maxima of the PU-based composite mat show identical behavior due to the chemical affinity between the two structures and the smallest fiber diameter. Moreover, the PU fiber mats exhibit long-lived bluish-green emission persisting over a large number of drops.Article Citation - WoS: 24Citation - Scopus: 30Solution Electrospinning of Polypropylene-Based Fibers and Their Application in Catalysis(Korean Fiber Society, 2016) Berber, Emine; Horzum, Nesrin; Hazer, Bakí; Demir, Mustafa MuammerSince the dissolution of polyolefins is a chronic problem, melt processing has been tacitly accepted as an obligation. In this work, polypropylene (PP) was modified on molecular level incorporating poly(ethylene glycol) (PEG) as graft segment (PP-g-PEG) in a range of 6 to 9 mol%. Gold nanoparticles were nucleated in the presence of the copolymer chains via redox reaction. The dissolution of the amphiphilic comb-type graft copolymers containing gold nanoparticles (80 nm in diameter) was achieved in toluene and successfully electrospun from its solution. The diameter of composite fibers was in the range from 0.3 to 2.5 μm. The design of the structurally organized copolymer fiber mats provided a support medium for the nanoparticles enhancing the active surface area for the catalytic applications. The resulting composite fibers exhibited rapid catalytic reduction of methylene blue (MB) dye in the presence of sodium borohydride (NaBH4) compared to corresponding composite cast film.Article Citation - WoS: 14Citation - Scopus: 14Polythiophene Derivative on Quartz Resonators for Mirna Capture and Assay(Royal Society of Chemistry, 2015) Palaniappan, Al.; Cheema, Jamal Ahmed; Rajwar, Deepa; Ammanath, Gopal; Xiaohu, Liu; Seng Koon, Lim; Yi, Wang; Yıldız, Ümit Hakan; Liedberg, BoA novel approach for miRNA assay using a cationic polythiophene derivative, poly[3-(3′-N,N,N-triethylamino-1′-propyloxy)-4-methyl-2,5-thiophene hydrobromide] (PT), immobilized on a quartz resonator is proposed. The cationic PT enables capturing of all RNA sequences in the sample matrix via electrostatic interactions, resulting in the formation of PT-RNA duplex structures on quartz resonators. Biotinylated peptide nucleic acid (b-PNA) sequences are subsequently utilized for the RNA assay, upon monitoring the PT-RNA-b-PNA triplex formation. Signal amplification is achieved by anchoring avidin coated nanoparticles to b-PNA in order to yield responses at clinically relevant concentration regimes. Unlike conventional nucleic acid assay methodologies that usually quantify a specific sequence of RNA, the proposed approach enables the assay of any RNA sequence in the sample matrix upon hybridization with a PNA sequence complementary to the RNA of interest. As an illustration, successful detection of mir21, (a miRNA sequence associated with lung cancer) is demonstrated with a limit of detection of 400 pM. Furthermore, precise quantification of mir21 in plasma samples is demonstrated without requiring PCR and sophisticated instrumentation.Article Citation - WoS: 20Citation - Scopus: 22A New Proton Sponge Polymer Synthesized by Raft Polymerization for Intracellular Delivery of Biotherapeutics(Royal Society of Chemistry, 2014) Kurtuluş, Işıl; Yılmaz, Gökhan; Üçüncü, Muhammed; Emrullahoğlu, Mustafa; Becer, C. Remzi; Bulmuş, VolgaA spermine-like polymer was synthesized via reversible addition- fragmentation chain transfer polymerization as a potential endosomal escaping agent. A new methacrylate monomer, 2-((tert-butoxycarbonyl)(2-((tert- butoxycarbonyl)amino)ethyl)amino)ethylmethacrylate (BocAEAEMA), was prepared and then polymerized via RAFT polymerization at constant monomer or initiator concentration at varying [M]/[R]/[I] ratios. In all polymerizations, ln[M] 0/[M] increased linearly with time. The linear increase in M n with monomer conversion was also observed. P(BocAEAEMA)s with controlled molecular weights and narrow molecular weight distributions were obtained. The in vitro cytotoxicity and proton sponge capacity of deprotected polymers P(AEAEMA) were investigated in comparison with a widely used endosomal-disruptive polymer, PEI. P(AEAEMA)s were found to possess proton sponge capacity comparable with PEI. More importantly, P(AEAEMA)s were not toxic on NIH 3T3 cells at concentrations where PEI (25 kDa) was highly toxic (0.4 μM and above). P(AEAEMA) was able to fully condense a DNA fragment at nitrogen/phosphate (N/P) ratios of 10 and above, as evidenced by gel electrophoresis. P(BocAEAEMA) was then chain-extended with a model sugar monomer, mannose-acrylate (ManAc), to yield P(AEAEMA)-b-P(ManAc) block copolymers, to potentially provide cell-recognition ability to the polyplex particles. Although the presence of the P(ManAc) block partially inhibited the interaction of P(AEAEMA) with DNA, P(AEAEMA)13-b-P(ManAc)7 was able to form polyplexes with DNA at N/P ratios ranging between 20/1 and 2/1. Dynamic light scattering measurements showed that while P(AEAEMA) (M n = 5.5 kDa) and DNA formed polyplex particles having a hydrodynamic diameter (Dh) of 125 ± 51 nm, P(AEAEMA)13-b- P(ManAc)7 and DNA formed particles with a smaller Dh of 38 ± 10 nm.Article Citation - WoS: 52Citation - Scopus: 53Raft Polymerization Mediated Bioconjugation Strategies(Royal Society of Chemistry, 2011) Bulmuş, VolgaThis review aims to highlight the use of RAFT polymerization in the synthesis of polymer bioconjugates. It covers two main bioconjugation strategies using the RAFT process: (i) post-polymerization bioconjugations using pre-synthesized reactive polymers, and (ii) bioconjugations via in situ polymerization using biomolecule-modified monomers or chain transfer agents. © 2011 The Royal Society of Chemistry.