Development of knitted and woven fabric for medical textiles

Bu çalışmada, yeterli antimikrobiyallik özelliğine sahip kullanım performansı yüksek örme ve dokuma tekstil yüzeylerinin geliştirilmesi amaçlanmıştır. Çalışma kapsamında bu özellikler kazandırılmak için hem elyaflardan gelen özelliklerden hem de kimyasallardan gelen antimikrobiyal özelliklerden faydalanılmıştır. Buna göre, çalışma kapsamında, üç farklı iplik numarasından (Ne 40/1, Ne 30/1 ve Ne 17/1) iki farklı eğirme yöntemi (Ring ve Vortex) kullanılarak farklı elyaflardan (pamuk, gümüş, tencel, bambu, poliester, kanallı poliester ve antibakteriyel poliester) iplikler üretilmiştir. Üretilen ipliklerden ise örme ve dokuma kumaş üretimleri gerçekleştirilmiştir. Örme kumaşlar üç farklı konstrüksiyonda (süprem, interlok ve iki iplik) üretilmiştir. Dokuma kumaşlar ise, iki farklı konstrüksiyonda (1/1 bez ayağı ve saten) farklı atkı ve çözgü ipliği kullanılarak üretilmiştir. Üretilen örme ve dokuma kumaşlara emdirme ve çektirme yöntemi ile Antibakteriyel ve su itici bitim işlemi uygulanmıştır. Geliştirilen kumaşlara fiziksel performans testleri, ısıl konfor testleri ve Antibakteriyel Aktivite, Bakteri Filtrasyon Etkinlik Testi, Nefes Alabilirlik (Basınç Farkı) ve Mikrobiyal Temizlik (Biyoyük) ölçümleri yapılmıştır. Elde edilen sonuçlar incelendiğinde, antibakteriyel apre uygulanmış örme kumaş (A) ve gümüş elyaf içeren örme kumaş (B1) numunelerin TSE K 599 standardına göre ve performans testlerine göre en uygun kumaşlar oldukları görülmüştür.In this project, it is aimed to develop technical textiles with sufficient antimicrobial properties with high usage performance. Within the scope of the study, both antimicrobial fibers and silver-added chemicals were used to gain these properties. Accordingly, within the scope of the project, yarns are spun from cotton, silver fiber, tencel, bamboo, polyester, polyester coolmax and polyester antibacterial fibers. In this project we used two different spinning methods (Ring and Vortex) from three different yarn counts (Ne 40/1, Ne 30/1 and Ne 17/1). Knitted and woven fabrics were produced from these yarns. Knitted fabrics have been produced in three different constructions (single jersey, interlock and 2-thread) and with different yarn mixtures. Woven fabrics, on the other hand, are produced in two different constructions (1/1 plain and satin) and using different weft and warp yarns. Antibacterial and water- repellent finishing processes 6 Carbon was applied to the knitted and woven fabrics. Performance tests, thermal comfort measurment and antibacterial activity, bacterial filtration efficiency, breathability (Pressure Difference) and Bioburden tests were performed on the developed fabrics. When the results obtained were examined, the knitted fabric (A) and knitted fabric with silver fiber (B1) sample completed all the measurements successfully

Fundamental characterization, photophysics and photocatalysis of a base metal iron(II)-cobalt(III) dyad

A new base metal iron-cobalt dyad has been obtained by connection between a heteroleptic tetra-NHC iron(II) photosensitizer combining a 2,6-bis[3-(2,6-diisopropylphenyl)imidazol-2-ylidene]pyridine with 2,6-bis(3-methyl-imidazol-2-ylidene)-4,4′-bipyridine ligand, and a cobaloxime catalyst. This novel iron(II)-cobalt(III) assembly has been extensively characterized by ground- and excited-state methods like X-ray crystallography, X-ray absorption spectroscopy, (spectro-)electrochemistry, and steady-state and time-resolved optical absorption spectroscopy, with a particular focus on the stability of the molecular assembly in solution and determination of the excited-state landscape. NMR and UV/Vis spectroscopy reveal dissociation of the dyad in acetonitrile at concentrations below 1 mM and high photostability. Transient absorption spectroscopy after excitation into the metal-to-ligand charge transfer absorption band suggests a relaxation cascade originating from hot singlet and triplet MLCT states, leading to the population of the $^{3}$MLCT state that exhibits the longest lifetime. Finally, decay into the ground state involves a $^{3}$MC state. Attachment of cobaloxime to the iron photosensitizer increases the $^{3}$MLCT lifetime at the iron centre. Together with the directing effect of the linker, this potentially makes the dyad more active in photocatalytic proton reduction experiments than the analogous two-component system, consisting of the iron photosensitizer and Co(dmgH)$_2$(py)Cl. This work thus sheds new light on the functionality of base metal dyads, which are important for more efficient and sustainable future proton reduction systems

Carbon Nanotubed Mediated Drug Delivery Approach Using Novel Antimicrobials

<p><strong>Original Conference Abstract</strong></p> <p>     The idea of employing carbon nanotubes (CNTs) as potential drug delivery vehicles is more than a decade old but a still emerging hot topic in the field. What still keep this topic so hot are not only the outstanding physical/chemical (high aspect ratio, strength, functionality...) properties of CNTs that have initially attracted scientists, but especially their potential side effects on the biological systems that left the researchers unconvinced for many years. The lack of standardized research methodology resulting in conflicting conclusions on the side effects of these unnatural/artificial materials have caused the CNTs to be highly questioned for the employment in biological applications. Consequently, the question of “whether the CNTs are really toxic” has become the most popular research problem.<br>     In the light of the conflicting literature data and the “unanswered toxicity” problems, CNT mediated cellular delivery of CNTs has been taken under investigation using novel antimicrobial agents. The recent study is not only expected to bring the novel antimicrobials into use but also to give answers on: i) the most reliable and stable methods for CNT functionalizations, ii) the most appropriate intra-cellular delivery mechanism for the drug, iii) the fate of CNTs after drug delivery, their bio-compatibility, iv) effects of different variables in the CNT properties, and, v) target based outcomes of the novel antimicrobial utilization in CNT research in comparison to the other reported active agents.<strong> </strong></p> <p> </p> <p>(The poster was awarded the "3rd Best Poster Award" at <em>Bioinnovation & ScanBalt Forum - International Conference on Molecular Biotechnology and Innovations for Healthy Life, Gdańsk | 16-18 of October 2013</em>)</p

Assembly of 1D Granular Structures from Sulfonated Polystyrene Microparticles

Being able to systematically modify the electric properties of nano- and microparticles opens up new possibilities for the bottom-up fabrication of advanced materials such as the fabrication of one-dimensional (1D) colloidal and granular materials. Fabricating 1D structures from individual particles offers plenty of applications ranging from electronic sensors and photovoltaics to artificial flagella for hydrodynamic propulsion. In this work, we demonstrate the assembly of 1D structures composed of individual microparticles with modified electric properties, pulled out of a liquid environment into air. Polystyrene particles were modified by sulfonation for different reaction times and characterized by dielectric spectroscopy and dipolar force measurements. We found that by increasing the sulfonation time, the values of both electrical conductivity and dielectric constant of the particles increase, and that the relaxation frequency of particle electric polarization changes, causing the measured dielectric loss of the particles to shift towards higher frequencies. We attributed these results to water adsorbed at the surface of the particles. With sulfonated polystyrene particles exhibiting a range of electric properties, we showed how the electric properties of individual particles influence the formation of 1D structures. By tuning applied voltage and frequency, we were able to control the formation and dynamics of 1D structures, including chain bending and oscillation

Electric Field-Driven Assembly of Sulfonated Polystyrene Microspheres

A designed assembly of particles at liquid interfaces offers many advantages for development of materials, and can be performed by various means. Electric fields provide a flexible method for structuring particles on drops, utilizing electrohydrodynamic circulation flows, and dielectrophoretic and electrophoretic interactions. In addition to the properties of the applied electric field, the manipulation of particles often depends on the intrinsic properties of the particles to be assembled. Here, we present an easy approach for producing polystyrene microparticles with different electrical properties. These particles are used for investigations into electric field-guided particle assembly in the bulk and on surfaces of oil droplets. By sulfonating polystyrene particles, we produce a set of particles with a range of dielectric constants and electrical conductivities, related to the sulfonation reaction time. The paper presents diverse particle behavior driven by electric fields, including particle assembly at different droplet locations, particle chaining, and the formation of ribbon-like structures with anisotropic properties

Polyamidoamine Dendrimers Decorated Multifunctional Polydopamine Nanoparticles for Targeted Chemo- and Photothermal Therapy of Liver Cancer Model

The development of multifunctional drug delivery systems combining two or more nanoparticle-mediated therapies for efficient cancer treatment is highly desired. To face this challenge, a photothermally active polydopamine (PDA) nanoparticle-based platform was designed for the loading of chemotherapeutic drug and targeting of cancer cells. PDA spheres were first functionalized with polyamidoamine (PAMAM) dendrimers followed by the conjugation with polyethylene glycol (PEG) moieties and folic acid (FA) targeting ligand. The anticancer drug doxorubicin (DOX) was then absorbed on the particle surface. We performed the physico-chemical characterization of this versatile material and we assessed further its possible application in chemo- and photothermal therapy using liver cancer cell model. These nanoparticles exhibited high near-infrared photothermal conversion efficacy and allowed for loading of the drug, which upon release in specifically targeted cancer cells suppressed their growth. Using cell proliferation, membrane damage, apoptosis, and oxidative stress assays we demonstrated high performance of this nanosystem in cancer cell death induction, providing a novel promising approach for cancer therapy

Polyamidoamine Dendrimers Decorated Multifunctional Polydopamine Nanoparticles for Targeted Chemo- and Photothermal Therapy of Liver Cancer Model

The development of multifunctional drug delivery systems combining two or more nanoparticle-mediated therapies for efficient cancer treatment is highly desired. To face this challenge, a photothermally active polydopamine (PDA) nanoparticle-based platform was designed for the loading of chemotherapeutic drug and targeting of cancer cells. PDA spheres were first functionalized with polyamidoamine (PAMAM) dendrimers followed by the conjugation with polyethylene glycol (PEG) moieties and folic acid (FA) targeting ligand. The anticancer drug doxorubicin (DOX) was then absorbed on the particle surface. We performed the physico-chemical characterization of this versatile material and we assessed further its possible application in chemo- and photothermal therapy using liver cancer cell model. These nanoparticles exhibited high near-infrared photothermal conversion efficacy and allowed for loading of the drug, which upon release in specifically targeted cancer cells suppressed their growth. Using cell proliferation, membrane damage, apoptosis, and oxidative stress assays we demonstrated high performance of this nanosystem in cancer cell death induction, providing a novel promising approach for cancer therapy

Calcite Nanotuned Chitinous Skeletons of Giant Ianthella basta Marine Demosponge

Marine sponges were among the first multicellular organisms on our planet and have survived to this day thanks to their unique mechanisms of chemical defense and the specific design of their skeletons, which have been optimized over millions of years of evolution to effectively inhabit the aquatic environment. In this work, we carried out studies to elucidate the nature and nanostructural organization of three-dimensional skeletal microfibers of the giant marine demosponge Ianthella basta, the body of which is a micro-reticular, durable structure that determines the ideal filtration function of this organism. For the first time, using the battery of analytical tools including three-dimensional micro&mdash;X-ray Fluorescence (3D-&micro;XRF), X-ray diffraction (XRD), infra-red (FTIR), Raman and Near Edge X-ray Fine Structure (NEXAFS) spectroscopy, we have shown that biomineral calcite is responsible for nano-tuning the skeletal fibers of this sponge species. This is the first report on the presence of a calcitic mineral phase in representatives of verongiid sponges which belong to the class Demospongiae. Our experimental data suggest a possible role for structural amino polysaccharide chitin as a template for calcification. Our study suggests further experiments to elucidate both the origin of calcium carbonate inside the skeleton of this sponge and the mechanisms of biomineralization in the surface layers of chitin microfibers saturated with bromotyrosines, which have effective antimicrobial properties and are responsible for the chemical defense of this organism. The discovery of the calcified phase in the chitinous template of I. basta skeleton is expected to broaden the knowledge in biomineralization science where the calcium carbonate is regarded as a valuable material for applications in biomedicine, environmental science, and even in civil engineering