Neslihan Nohut Maslakci

Ibuprofen and acetylsalicylic acid loaded electrospun PVP-dextran nanofiber mats for biomedical applications

The aim of this work is to investigate the suitability of electrospinning for biomedical applications and to produce fast-dissolving drug delivery through uniform dextran nanofiber nonwoven maps. To prepare oral fast-dissolving drug delivery nonwoven maps via electrospinning technology, ibuprofen (Ibu) and acetylsalicylic acid (ASA) as the model drugs, and polyvinylpyrrolidone (PVP), dextran T10 (Dext T10) and dextran T40 (Dext T40) as the filament-forming polymer and drug carrier were selected. Morphology of nanofiber samples was characterized by scanning electron microscopy/energy dispersive X-ray spectroscopyxa0(SEM/EDS). SEM images showed homogeneous dispersion of drugs into the polymer blends. The structure analysis made by attenuated total reflectance/Fourier transform infrared spectroscopy suggested that PVP/dextran and drug blended very well in the nanofibers. The amount of ibuprofen and acetylsalicylic acid in a nanofiber samples was determined using reverse-phase high-performance liquid chromatography. The results showed that the ibuprofen content in PVP/Dext T40-Ibu and PVP/Dext T10-Ibu nanofiber samples (431.7xa0±xa039.7 and 528.3xa0±xa024.7xa0µg/mL, respectively) is significantly higher than acetylsalicylic acid content in PVP/Dext T40-ASA and PVP/Dext T10-ASA nanofiber samples (145.5xa0±xa05.6 and 168.3xa0±xa07.3xa0µg/mL, respectively). Antibacterial properties of the fiber samples containing drug against Gram-negative (Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922) and Gram-positive bacteria (Staphylococcus aureus ATCC 25923, Bacillus subtilis ATCC 6633) were examined. The PVP-drug containing nanofibers resulted in a superior antibacterial activity than PVP/dextran-drug containing nanofibers. PVP/Dext T10 and PVP/Dext T40 nanofibers have the potential to be used as solid dispersions to improve the dissolution profiles of poorly water-soluble drugs and/or fast disintegrating drug delivery systems.

QCM-DNA biosensor based on plasma modified PT/TiO2 nanocomposites

ABSTRACT A quartz crystal microbalance DNA biosensor based on plasma prepared polythiophene /titanium dioxide (PT/TiO2) nanocomposite was developed for the detection of genetically modified organisms (GMOs). DNA hybridization was studied by quartz crystal microbalance (QCM) and cyclic voltammetry (CV) measurements. Single stranded DNA probes were immobilized on the PT/TiO2 coated quartz crystal electrode and the hybridization between the immobilized probe and the target complementary sequence in solution was monitored. The developed QCM-DNA biosensor represented promising results for a real-time, label-free, direct detection of DNA samples for the screening of genetically modified organisms.

Chemical synthesis and characterization of poly(3,4-ethylenedioxythiophene)/tungsten composite materials in the presence of ionic liquids

Abstract Poly(3,4-ethylenedioxythiophene)/tungsten (PEDOT/W) composites were prepared by an in situ chemical oxidative polymerization of 3,4-ethylenedioxythiophene in different ionic liquids; 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF4), 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6), 1-butyl- 3-methylimidazolium bis(trifluoromethylsulfonyl) imide (BMIMTFSI), and 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl) imide (BMPTFSI). These polymer/metal hybrids (PEDOT/W) were subsequently characterized for their structural, crystalline, thermal and morphological properties by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The significant enhancement in properties can be attributed to the nanoscale particle size and uniform size distribution of PEDOT/W and the synergistic effect between the inorganic nano-W and organic PEDOT material.

Poly(vinylferrocene)/Cellulose Acetate Fibers: A New Approach for In-Situ Monitoring Process Through QCM and Electrospinning Studies

A poly(vinylferrocene) (PVFc)/cellulose acetate (CA) fibers were obtained using an electrospinning method. The electrospinning process was controlled in situ with a quartz crystal microbalance (QCM) system. Fiber formation was observed through adjusting PVFc concentration. Morphological characteristics depending on the changes of atomic % ratio value of PVFc/CA electrospun fibers was investigated by scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy analysis. Electrochemical behavior of PVFc/CA electrospun fibers was investigated by using cyclic voltammetry measurements based on the Fc+/Fc redox couple. The results indicated that PVFc deployed in/on the CA fibers and aggregated arbitrarily on the QCM electrode. The new PVFc/CA electrospun fibers were used for anion sensing.

Electrospun fibers coated onto plasma modified and nonmodified wools

Summary form only given. Unlike conventional fiber spinning techniques (wet spinning, dry spinning, melt spinning, gel spinning), electrospinning has been recognized as simple effective and an efficient technique for the fabrication of polymer nanofibers and nanofiber non-wowen mats1,2. Moreover, this technique can provide possibility to control over the resultant morphology of the nanofiber3.

A study on characterization of polymer-coated wool fabrics using plasma polymerization

Many great investigations and new techniques focused on the study of textile to improve textile surface properties such as wetting, antistatic, electrical conduction, penetration, and so on1,2. The static charge is a critical factor and an important limitation for many applications such as garments in direct contact with human skin3,4. Both low-pressure and atmospheric plasma systems can be used for novel antistatic acquisition; processing fibers, yarns, fabric. Wool is good substrate for plasma modification due to outermost part of fiber that is consisted of lipid layers and ionizable functional groups5,6.

RF rotating plasma modified of chitosan with 3,4-ethylenedioxythiophene, thiophene and furan: Investigation of nanofibers in-situ with quartz crystal microbalance (QCM) and electrospinning system

Chitosan is a biocompatible aminopolysaccharide, N-deacetylated biopolymer of chitin that is the second abundant natural polymers on the earth1,2. Because of its favorable physicochemical and biological properties such as its being biocompatible, low toxicity, ecological safety and biodegradable, chitosan is considered as an attractive material that can potentially be used in the biomedical and pharmaceutical fields3-7. Nevertheless, recent researches have been focused on modification of the surface of chitosan using the different methods7.

Plasma modified chitosan/N-acetyl-2-pyrazoline derivative nanofibers

A series of plasma modified chitosan/N-acetyl-2-pyrazoline derivative fibers (PMCh/NAP) were obtained by using an electrospinning method. The result compounds were synthesized from chalcones which obtained by Claisen-Schmidt condensation of ferrocenecarboxaldehyde with hetaryl methyl ketones1. The synthesized chalcone derivatives were then treated with hydrazine hydrate in glacial acetic acid medium to produce N-acetyl-2 pyrazoline derivatives2.