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International audience; Although acetone, in DESI ionisation generally leads to protein aggregation, in this study we report unexpected multi-proton transfers to lysozyme using this aprotic solvent as a charged spray. The DESI/acetone mass spectrum of lysozyme displays (i) a significant increase in the average charge state (Zav) and (ii) an incomplete H+/Ca2+ exchange, even though the overall contribution of cationised species is high, relative to those from spraying with a methanol/water solvent. This behavior is contrary to that expected from gas phase basicity, because GBacetone >GBmethanol. Decreasing the amount of sample deposited on the target (from 50 to 0.050 pmole) leads to a charge state increase, as seen in ESI, but not in the extent of cationisation. Moreover, the DESI signal duration is extended with sprayed acetone even though the total ionic current is significantly lowered. With a d6-acetone spray, no incorporation of a deuteron occurs, and the ionization yield is strongly decreased for multi-protonated lysoi+ lysozyme. This is in contrast to that observed with a d4-methanol spray, which displays a distribution of 48 deuterons in the lyso9+ ion as shown in high resolution with a LTQ/Orbitrap instrument. This unexpected behavior of the (CD3)2CO spray suggests that protons do not originate from acetone. Furthermore, dry argon post-flow on the target surface results in the lysozyme signal suppression, whereas with a humid argon flow, the signal is regenerated. On the other hand, an argon stream bubbling in heavy water, yields incorporation of several deuterons. The interpretation of this behavior is explained by considering the acetone radical ions at the surface of the primary droplets (and/or offspring droplets and/or at the wet sample surface), being able to react with ambient moisture (or with traces of water adsorbed at liquid phase). Under these conditions, enough protons are produced to generate multi-charged solvated lysozyme aggregates which then become desolvated in the reduced pressure in the skimmer area.

The most important phase in textile finishing processes is adsorption of chemical compounds and substances on textile materials surface. Lyocell fibers, like most textile fibers, are negatively charged in neutral and alkali aqueous solutions. Therefore, the adsorption of anionic textile auxiliaries, dyestuffs, optical brighteners and finishing agents is difficult due to repulsive forces. Therefore, in this paper Lyocell fibers were cationized with three different compounds - short chain quaternary ammonium compounds, 3-chloro-2-hydroxypropyl-trimethyl ammonium chloride (CHPTAC), and long chain commercial products for the same purpose – cationic reactive polyammonium compounds Rewin OS (CHT/Bezema), and Rewin DWR (CHT/Bezema). Surfactants are essential for wet treatment of textiles. Its adsorption highly depends on ionogenity, particle size, and length of hydrophobic part as well as treatment conditions applied. For that reason, the ionic surfactant adsorption below and above critical micellar concentration (CMC) were investigated, as well as electrokinetic potential and specific amount of surface charge of such cationized Lyocell fibers.

Bu tez kapsamında, tekstil sanayinde yaygın olarak kullanılan poliamid/elastan kumaşların 1:2 metal kompleks boyarmaddeleriyle verim kaybına yol açmadan kaynama noktasının altındaki sıcaklıklarda boyanabilme ve kısa fiksaj sürelerinde basılabilme imkânları incelenmiştir. Tez projesinde öncelikle poliamid kumaşların düşük sıcaklıkta boyanması ve kısa fiksaj süresinde basılmasını sağlama amacı ile lifleri kimyasal modifikasyona uğratacak bir yardımcı kimyasalın ve bunun aplikasyonuna ilişkin yöntemin geliştirilmesi üzerinde çalışmalar yapılmıştır. Yapılan denemeler sonucunda boyama sıcaklığını 80°C'a düşürebilmek için katyonikleştirme işleminin optimum koşullarının, pH 7, 60°C, 30 dk. ve %5'lik konsantrasyon olduğu tespit edilmiştir. Ayrıca katyonikleştirme işlemi sonrası poliamid kumaşların renk verimi ve haslıklarında herhangi bir kayba uğramadan baskı sonrası fiksaj süresinin 30 dakikadan 15 dakikaya kısaltılabileceği görülmüştür. Tez kapsamında poliamid kumaşların düşük sıcaklıkta boyanması ve kısa fiksaj süresinde basılmasını sağlama amacı ile uygun düşük sıcaklıkta boyama yardımcı kimyasalının ve bunun aplikasyonuna ilişkin yöntemin geliştirilmesi konusunda da çalışmalar yapılmıştır. Deneysel çalışmaların sonucuna göre boyamada bütil-isopropil ftalimid esaslı yardımcı kimyasal kullanılmasının gerek boyamada sıcaklığın düşürülmesi gerekse baskıda fiksaj süresinin kısaltılması hususlarında pek bir fayda sağlamadığı söylenebilir. Within this thesis, dyeability of the polyamide/elastane fabrics, which are commonly used in textile industry, below the boiling temperature with 1:2 metal complex dyes without causing loss of efficiency and their printability under short fixation periods were examined. In this thesis project, firstly studies on developing an auxiliary, which can modify fibers chemically, and its application process were carried out with the aim of making possible to dye polyamide fabrics at low temperatures and print at short fixation periods. As a result of experiments, optimum conditions of cationization treatment were determined as pH 7, 60°C, 30 min. and a concentration of 5% for decreasing dyeing temperature to 80°C. Furthermore it was observed that fixation time after printing could be shortened from 30 min. to 15 min. Without a loss in color efficiency and fastness of polyamide fabrics after cationization treatment. Within this thesis project, studies also on developing a suitable low temperature dyeing auxiliary and its application process were carried out with the aim of making possible to dye polyamide fabrics at low temperatures and print at short fixation periods. According to the results of experimental studies, it can be said that the usage of butyl-isopropyl phtalimide based auxiliary does not provide benefits neither in lowering dyeing temperature nor shortening the fixation time in printing. 55

The objective of this study is to enhance in vivo ectopic bone formation by combination of plasmid DNA impregnation into three-dimensional (3-D) cell scaffolds and a developed in vitro culture method. Gelatin was cationized by introducing spermine (Sm) to the carboxyl groups for complexation with the plasmid DNA. As the MSC scaffold, collagen sponge reinforced by incorporation of poly(glycolic acid) (PGA) fibers was used. A complex of the cationized gelatin and plasmid DNA of BMP-2 was impregnated into the scaffold. MCS were seeded into each scaffold and cultured by a static and perfusion methods. When MSC were cultured in the PGA-reinforced collagen sponge, the level of BMP-2 expression was significantly enhanced by the perfusion culture compared with static method. When the osteoinduction activity of the PGA-reinforced collagen sponges seeded with PBS, MSC, naked plasmid DNA-BMP-2, cationized gelatin-plasmid DNA-BMP-2 complex, and transfected MSC by static and perfusion method, were studied following the implantation into the back subcutis of rats in terms of histological and biochemical examinations, homogeneous bone formation was histologically observed throughout the sponges seeded with cationized gelatin-plasmid DNA of BMP-2 complex and transfected MSC by perfusion method, although the extent of bone formation was higher for the later one. The level of alkaline phosphatase activity and osteocalcin content at the implanted sites of sponges seeded with transfected MSC by perfusion method were significantly high compared with those seeded with other agents. We conclude that combination of plasmid DNA-impregnated PGA-reinforced collagen sponge and the perfusion method was promising to promote the in vitro gene expression for MSC and in vivo ectopic bone formation.

The majority of known cytotoxic RNases are basic proteins which destroy intracellular RNA. Cationization of RNases is considered to be an effective strategy for strengthening their antitumor properties. We constructed a set of RNase Sa variants consisting of charge reversal mutants, charge neutralization mutants, and variants with positively charged cluster at the N-terminus. All constructs retain a high level of catalytic activity and differ in net charge. Using acute myeloid leukemia cells Kasumi-1 we have shown that (i) cytotoxicity of RNase Sa mutants is linearly enhanced by cationization, (ii) the ability of cytotoxic mutants to induce cell death is caused by induction of apoptosis and (iii) localization of positive charge on N-terminus does not contribute to RNase Sa cytotoxicity. Capacity to induce apoptosis in malignant cells and the absence of necrotic effects make the RNase Sa mutants with high positive charge a suitable anti-cancer agent.

International audience; Microencapsulation of hydrophobic (α-tocopherol) and hydrophilic (ascorbic acid) vitamins by native (non-modified) and modified soy protein isolate (SPI) was carried out using a spray-drying technique. Proteins' functional properties were modified by acylation and cationization reactions in aqueous alkaline media. The results obtained demonstrated that SPI modification resulted in decreased emulsion droplet size and viscosity. All preparations with ascorbic acid (AA) had lower viscosity and microparticle size than those with α-tocopherol (T). Moreover, grafting of fatty acid chains to SPI by acylation improved its amphiphilic character and affinity with hydrophobic substances. Thus, the microencapsulation efficiency of T was increased from 79.7% to 94.8% and the microencapsulation efficiency of AA was reduced from 91.8% to 57.3% compared to native SPI. Conversely, attachment of quaternary ammonium cationic groups to proteinic chains by cationization, increased SPI solubility and favored the AA microencapsulation. This study illustrated that an appropriate modification of SPI can improve the microencapsulation efficiency of suitable active cores.

Lama ailesine mensup olan Alpaka (Lama pacos)'dan elde edilen liflere alpaka adı verilmektedir. Alpakanın en önemli özelliği ipeğimsi, yumuşak tutumudur. Alpakanın değerli olmasına yol açan diğer özellikleri arasında parlaklığı, dayanımı, çok sıcak tutması (yapısındaki mikroskobik boyuttaki hava boşlukları sayesinde havayı hapsettiğinden yüne göre 7 kat daha sıcak tutmaktadır), dökümlülüğü, boyayı çok iyi alması ve pillinglenme eğilimi olmaması sayılabilir. Bu lifler dünyada oldukça dar bir alanı kapsayan spesifik bölgelerde bulunmakta olup çok küçük miktarlarda üretilmektedirler. Tüm bu faktörler bu liflerden yapılmış ürünlerin pahalı olmasına yol açmaktadır ve bu nedenle söz konusu lifler `Lüks Lif` olarak nitelendirilmektedir.Lüks lifler fiyat bakımından yün ile karşılaştırılacak olursa, bu liflerden üretilen kumaşların yünlü mamullere göre oldukça pahalı olduğu görülmektedir. Dolayısıyla alpaka, katma değeri yüksek değerli bir liftir. Tekstil ürününün katma değerini arttıran en önemli işlem basamağı ise terbiye işlemleridir. Alpaka liflerinin terbiye işlemlerinde özellikle boyama adımında çeşitli sorunlarla karşılaşılmaktadır. Bu liflerin boyanmasındaki temel sorun, koyun yününde uygulanan kaynama sıcaklığında boyama işleminin bu liflerin çeşitli özelliklerine zarar vermesidir. Eğer renk veriminde düşüşe yol açmadan düşük sıcaklıkta boyama başarılabilirse, liflerin çeşitli özelliklerinin (parlaklık, dayanım vb.) korunmasının ve boyamadaki enerji sarfiyatının azaltılmasının yanı sıra, daha iyi boyanma özelliklerini elde edilebilecektir. Bu projede, alpaka liflerinin verim kaybına yol açmadan çeşitli boyarmadde sınıflarıyla kaynama noktasının altındaki sıcaklıklarda (80 veya 90°C) boyanabilme imkânları araştırılacaktır. Bu amaçla; boyama öncesi liflere katyonikleştirilmesi işlemi uygulanması üzerinde çalışılacaktır. Bunun ötesinde liflerin boyanma düzgünlüğünün geliştirilmesi için çeşitli yardımcı maddelerin kullanımı ve boyama koşullarının ayarlanması üzerinde çalışılarak boyama kalitesi arttırılacaktır. Alpaka gibi katma değeri yüksek liflerin boyanmasında bir diğer önemli konu moda yaratacak etkilerin eldesidir. Bu nedenle, proje kapsamında ayrıca, liflere çeşitli modifikasyonlar uygulayarak liflerin boyanmasında `multicolor efekt` eldesi üzerinde de çalışılacaktır.Anahtar kelimeler:Alpaka, boyama, katyonikleştirme, düzgünlük, multicolor Alpaca is relative to llama family (Lama pacaos) and obtained from this animals fiber is called alpaca. Most feature of alpaca fiber is silk touch handle. Other features of alpaca fibers are luster, strength, keep warm (its structre has microscopic air spaces so keep air inside and this gives warmer feature seven times than wool), drape, and perfect take in dyestuff, less pilling. These fibers exist in rarely specific area in world and are produced less amount. All these factors give more expensive price made by this fiber and for that reason mentioned fiber is characterized `Luxry Fiber`.If luxry fibers compare with wool about price, it is easy to see that made from these fibers fabrics are much more expensive than wool stuff. Hence alpaca is valuable and profitable fiber. Another profitable process is treatment of textile materials. On treatment of alpaca fibers especialy in dyeing process there are some problem to face. The main complication of this fiber dyeing is when dyeing at boiling temperature like conventional wool, alpaca fibers some specialties are badly affected by this process. If it is possible to dye that without any decrease of yield by low temperature, some features of fiber (luster, strenght etc) can protect and this gains saving of energy.In this project alpaca fibers' dyeability will search by different kind of dyestuff without any yield under boling degree celcius (80 or 90°C). For that reason the first thing is that cationication on fibers before dyeing. Furthermore dyeing quality will increase by using different kind of agent and regulation of dyeing process for improve of dyeing levellness. Another isue is that fashion side of alpaca fibers profitable and different effect on dyeing. For this purpose in this project alpaca fibers will modified by applications for `multicolor effect` will investigate.Keywords:Alpaca, dyeing, cationication, levelness, multicolor 63

Cotton fibers develop a negative charge when immersed in water. Reactive dyes, which are most commonly used to dye cotton fibers, are also negatively charged in solution. The negative charge developed on the fiber surface repels negative dye molecule, which limits the efficiency of dye uptake (low % exhaustion). To overcome this problem a large amount of salt is used to neutralize the repulsion forces between the fabric and the dye. The salt used is neither exhausted nor destroyed and hence remains in the dye bath after dyeing. The large amount of salt concentration in the effluent has a negative environmental impact. One of the approaches to eliminate salt during the dyeing process and to improve the dye uptake on cotton fabric is cationization of fiber/fabric. In this study, dyeing kinetics and dye-uptake was studied on 1) chemically cationized 100% cotton fabrics 2) fabric made from composite yarn (chitin/cellulose and viscose) and 3) fabric made from genetically modified fibers. The dye uptake property is enhanced on cationized cotton fibers or cotton fabrics due to the addition of cationic sites. These cationic sites attract negatively charged dye molecules, which increases the % exhaustion. Both fabrics made from cationized cotton fiber or chemically cationized fabric can be dyed with high efficiency without salt and without alkali in relatively short dyeing time. Therefore, cationization of fiber or fabric could be a viable option to increase the % exhaustion without using salt and alkali. Additionally, the high % exhaustion of dye on cationized fabric lowers the amount of dye in dye effluent discharged from the dyeing operations which decreases water pollution. Dye uptake was also analyzed on the knitted fabric produced from Quickspin yarn. The dyeing kinetics and the final % exhaustion of fabric produced from Quickspin yarn are identical to the fabric produced from commercial Ring spun yarn. There is a good correlation between K/S of knitted fabrics produced from QuickSpin yarn and Rotor spun yarn. The results indicate that the dye-uptake is not affected by the spinning technology. The only parameter that has significant impact on the dye uptake is the fiber micronaire. Therefore, Quickspin yarn can be successfully used to access dye uptake efficiency on very small amount of cotton fibers (~10g).

Native galactoglucomannans (GGMs), which were isolated from thermomechanical pulping waters of Norway spruce, were modified through cationization, carboxymethylation, and imination at the reducing end with a primary long-chain hydrocarbon amine. The derivatives were tested for their papermaking properties. The native GGMs increased the wet tensile strength as a result of the dispersion of fibrils in the wet fibre web. In wood-containing paper, GGMs increased the retention of fines and extractives without a decrease in paper strength. The GGMs also flocculated fillers effectively. The cationic GGMs were able to interact between fibrous fine material and fibres, as well as with fillers. Therefore, an electrostatic mechanism of action is suggested. Carboxymethylated GGMs are believed to bind to fibres and fines through divalent metal ions present in wood. For the amphiphilic amine-modified GGMs, the alkane chain attached to the reducing end appeared to play a key role. The tail was orientated towards the hydrophobic particles; the resulting paper was the most hydrophilic, since the hydrophobic particles were covered with the polysaccharide. Based on the present results, it can be concluded that galactoglucomannans can be modified to yield new and interesting functionalities to wet-end additives for papermaking and other purposes.

BIOVERT+VBI:CPI:FRA; Cationizations of galactomannan- and xylan-type hemicelluloses were performed in a solid state, with 2,3-epoxypropyltrimethylammonium chloride (ETA) as the cationic reagent under alkaline conditions. By this method, the reaction efficiency was significantly increased for all hemicellulose types, up to 90% in the case of xylan. The consumption of reagents was reduced by a factor of ten when compared to the reaction in liquid phase, while comparable values of the degree of substitution (DS) were obtained. By reducing the number of purification steps, the consumption of solvents was limited, and high mass yields were preserved. By all aspects, this method constitutes an economical and environmental gain for the cationization reaction of hemicelluloses. Native hemicelluloses and their cationic derivatives were tested as additives to the pulp slurry in order to increase the dry strength of the paper formed. The cationization of hemicelluloses had a beneficial effect on the mechanical properties of paper, with a supplementary gain of properties compared to the unmodified polysaccharides. Cationic derivatives of a DS 0.3 gave the best results for both polysaccharides, with the galactomannan-type being more efficient than the xylan-type with a 90% increase of the burst index.

Interface phenomena have a significant role in the wet finishing processes. Therefore, in this paper electrokinetic phenomena of cotton fabric cationized with commercial cationic compound was researched. After cationization, the characterization of surface and chemical composition was performed by FTIR-ATR. Electokinetic phenomena - Zeta potential, Isoelectric point (IEP) and Point of zero charge (PZC), were determined according to streaming current/streaming potential method and specific amount of surface charge according to back-titration method. The affinity of such modified cotton to reactive dyestuff of different functional groups was investigated trough the K/S values. The influence of electrolyte addition to dye bath was investigated as well.

Cotton fabric is mostly dyed with reactive dyes. Reactive dyeing of cotton requires a large amount of salt for the exhaustion of dye from the dyebath onto the fiber. Considerable amount of dyes is hydrolyzed. Dyeing of cotton with reactive dyes has serious environmental impact as large volume of highly colored and saline effluent is discharged. The process named cationization allows dyeing cotton fibers without using salt. This process consists of a chemical modification of cellulosic macromolecules to introduce positively charged sites. In this study, cotton fabric was cationized using 3-chloro-2-hydroxylpropyl trimethyl-ammonium chloride (CHPTAC). The assessment of dye uptake was investigated with two reactive dyes, CI Reactive Blue 235 and CI Reactive Blue 19. Dye exhaustion kinetics were established using the Datacolor-HueMetrix Monitor system. The color of the fabric at the end of the dyeing cycle was measured using Macbeth colorimer. The Analysis of Variance (ANOVA) shows statistically significant effect of the CHPTAC concentration (treatment) and the exhaustion time. There is also significant interaction treatment*exhaustion time.

Wastewater effluents from textile industry mainly contain dyes used in the dyeing or printing of textiles yarns or fabrics. A lot of technologies can be adopted for dye removal from wastewaters, including biological treatments based on activated sludge, adsorption on activated carbon, or membrane processes. Nevertheless, none of these methods is performing toward all classes of dyes; treatment plants of great dimensions and difficult handling can be required, while cost can be prohibitive. In the present study, dye adsorption was performed on low-cost fibrous cellulose materials, submitted to a cationization process using a quaternary ammonium reagent. These materials were characterized by FTIR–ATR spectroscopy, while the treatment efficiency was investigated through exhaustion and kinetic adsorption tests toward anionic dyes, such as acid, direct, reactive, and a cationic dye. Comparisons were carried out between treated and untreated samples, and with activated carbon. Best results were obtained with cationized cotton, both in linters or “tulle” fabric form, showing good performance toward all the investigated dyes. Tests in continuous flow confirmed the good behavior of these materials, but tulle fabric was better as filtration medium for a lower pressure drop. Finally, regeneration tests by bleaching were carried out finding that regenerated material maintained good adsorption power.

Cationized agaroses with different degrees of substitution (0.04–0.77) were synthesized, employing 3-chloro-2-hydroxypropyltrimethylammonium chloride (CHPTAC). The influence of different reaction parameters on the substitution degree and molecular weight was evaluated. The investigated parameters were concentration of reagents, temperature, time, and addition of NaBH4. The products were characterized by means of scanning electronic microscopy, infrared spectroscopy, viscosimetry, and NMR spectroscopy. Methanolysis products were studied by electrospray ionization mass spectrometry. The higher the concentration of CHPTAC employed, a higher degree of substitution was obtained, if the optimum concentration of NaOH in each case was employed. Insufficient quantities of NaOH reduced epoxide formation and the reacting alkoxides of the polysaccharide, whereas an excess of NaOH favored degradation of the epoxide and decrease in the molecular weight of the product. A reaction time of 2 h was sufficient to obtain products with the maximum degree of substitution for each case. The addition of NaBH4 gave products with a slightly higher molecular weight, but the extra cost involved should not justify its use for large-scale application. Fil: Prado, Héctor Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones En Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones En Hidratos de Carbono; Argentina Fil: Matulewicz, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones En Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones En Hidratos de Carbono; Argentina Fil: Bonelli, Pablo Ricardo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Cukierman, Ana Lea. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Tecnología Farmacéutica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

During the twin extrusion process, starch basic structure is modified and it is very important to be able to predict the changes experienced by the product. To model the transformation of starch during twin screw extrusion, it is thus necessary to take into account the strong coupling between viscosity and thermomechanical treatment. It is the purpose of the present work. We have used the software Ludovic© to calculate the flow of a molten starch along a twin screw extruder. We have assumed that the degradation reaction (viscosity decrease) was linked to the specific mechanical energy received during the flow. We have compared extrusion cases with and without viscosity/energy coupling, and we show that it is important to take it into account to correctly predict the parameters of the extrusion process (torque, energy, product temperature, etc.) and the level of starch transformation. POLYM. ENG. SCI., 50:1758–1766, 2010. © 2010 Society of Plastics Engineers

The main aim of this work was to synthesize water-soluble chitosan – methoxy poly(ethylene glycol) (MPEG) graft copolymers and cationized chitosan derivatives of various structure and desirable graft density, and to study their properties. Novel chitosan-MPEG derivatives with different degree of substitution of chitosan were prepared for the first time by “click” chemistry. Several new schemes of the synthesis of chitosan-MPEG and additionally cationized chitosan derivatives were suggested based on protection of amino functionality by using chitosan-dodecyl sulphate complexes. Additional cationization of chitosan through its hydroxyl groups in alkaline medium enabled to prepare chitosan derivatives with very high charge density. A method of enzymatic hydrolysis of the cationized chitosans was proposed which allowed a tenfold decrease of the molecular weight of chitosan derivatives. Modification of chitosan by tartaric, citric or adipic acid yielded chitosan nanoparticles. Further modification of chitosan nanoparticles by dithiobenzendicarboxylate resulted in RAFT macroinitiators used as precursors of functionalized nanoparticles. Pagrindinis šio darbo tikslas buvo susintetinti vandenyje tirpius norimos struktūros bei pakeitimo laipsnio skiepytuosius chitozano – polietilenglikolio (MPEG) kopolimerus bei katijonizuotus chitozano darinius ir ištirti jų savybes. Įvairaus pakeitimo laipsnio chitozano-MPEG skiepytieji kopolimerai susintetinti vykdant „klik“ chemijos reakcijas. Pasiūlyti nauji chitozano-MPEG bei papildomai katijonizuoto chitozano sintezės būdai, chitozano aminogrupių apsaugai naudojant chitozano kompleksus su dodecilsulfatu. Dalinai katijonizuoto chitozano darinius papildomai katijonizuojant šarminėje terpėje, gauti chitozano dariniai, turintys labai didelį krūvio tankį. Pasiūlytas katijonizuoto chitozano fermentinės hidrolizės metodas, kurį naudojant chitozano darinio molekulinę masę lengvai galima sumažinti dešimtimis kartų. Chitozaną modifikuojant vyno, citrinų arba adipo rūgštimis, susintetintos nanodalelės. Prie chitozano nanodalelių prijungus (4-cianpentano rūgšties)-4-ditiobenzenkarboksilatą, susintetintas makroiniciatorius gyvybingajai radikalinei polimerizacijai RAFT metodu.

Textiles are characterized by its inner and outer structure and functional groups. Specific adsorption of ions or dissociation of the surface groups in aqueous solution results with their surface charge. Different treatments, mostly alkaline modifications of fibers, change surface charge and adsorption ability. Cationization, as an alternative method for improving dyestuff and surfactant adsorption, increases cotton zeta potential and change the fiber surface charge influence significantly on cotton adsorption properties. The present paper deals with systematic investigations of the interface phenomena of cationized cotton fabric with short chain quaternary ammonium compound 2, 3-epoxypropyl trimethyl ammonium chloride (EPTAC) before, during and after mercerization process. The water, ionic surfactant and dyestuff adsorption, as well as electrokinetic potential and specific amount of surface charge of modified cotton fabrics are researched. By comparing mercerized and cationized cotton, it was found that cationized cotton retains all the beneficial properties of mercerized cotton with a change of surface charge that ensures further quality improvement.

Interface phenomena have a significant role in the wet finishing processes. It occurs between liquid and solid phases (e.g. baths – textiles). Although these systems are extremely complex, systematic study of interface phenomena of cotton fabric lead to knowledge of the mechanisms in textile wetting, finishing and dyeing processes setting the base that can be used to predict fabric behavior in the wet finishing, and to some extent to assess the value and utilization characteristics, and environmental acceptability of the product for a particular application. The present paper systematically investigates the interface phenomena of modified cotton fabric (by mercerization and cationization). Mercerization is performed following the technological process. Cationization was performed with short chain quaternary ammonium compound 2, 3-epoxypropyl trimethyl ammonium chloride (EPTAC) before, during and after mercerization process. Cotton fabrics modification was researched by cationization through structural properties of fabrics, FTIR and TGA. Interface phenomena of cationized cotton fabrics were investigated through surface free energy, pore volume distribution (PVD), water, ionic surfactant and dyestuff adsorption, hydrophility, electrokinetic potential and specific amount of surface charge. By comparing mercerized and cationized cotton, it was found that cationization during the mercerization process results in new material giving to cotton a new dimension of pretreatment and finishing. The modified cotton retains all the beneficial properties of mercerized cotton with a change of surface charge that ensures further quality improvement. It was found that cationization with short chain cationic compounds completely change the system dyestuff-cotton fiber and do not obey any known law, which indicates the necessity of further investigations of such modified cotton. Additionally, this modification presents an exceptional potential for environmental disposal of waste as well, since such modified cotton fully adsorbs anionic dyestuff.

Cotton, like most textile fibers, is negative charged in neutral and alkali aqueous solutions. Dyestuffs, optical brighteners and finishing agents in aqueous solution have the same electrical charge as cotton. Therefore, adsorption processes are difficult due to these repulsive forces. This paper studies the application of water extraction plants of St. Johns wart, marigold and hibiscus for the finishing of modified cotton – by mercerization and cationization. The mercerization is the oldest modification since 19th century, while the cationization is researched in last 10 years. In this paper cationization of cotton fabric for achieving electropositive charge and better adsorption properties was carried out with cationic compound, quaternary ammonium salt during the mercerization well as with commercial product for cationization Denimcol Fix-GF (Bezema). The cotton electrokinetic phenomena after modifications were determined by zeta potential, isoelectric point, point of zero charge and specific amount of surface charge. The adsorption ability of plant extracts with and without mordant was investigated.

This paper deals with interface phenomena of pretreated and modified cotton fabric. The most important phase in textile finishing processes of cotton fabrics is adsorption of chemical substances and compounds on textile materials surface and wet-ability as well. Due to existing repulsion forces, adsorption of dyestuffs, fluorescent whitening agents and other textile auxiliaries is not easy to perform. This can be overcome with large amount of electrolyte addition, what is economically and ecologically unfavorable. Therefore, for the future textiles alternative methods have been researched. One of those is cotton modification using amines and/or quaternary ammonium compounds. Modification of cotton fabric for achieving electropositive charge was carried out by cationization before and during the mercerization process. Interface phenomena result in change of textile surface free energy. Electrokinetic phenomena characterize electric charge of textile material, while contact angle characterize its wet-ability. The effect of modification on the change of fabric zeta potential, surface free energy, contact angle, specific amount of surface charge, ionic surfactant and dyestuff adsorption ability were discussed.

The most important phase in textile finishing processes is adsorption of chemical substances and compounds on textile materials surface and wettability as well. Interface phenomena happen between liquid and solid phase, like water solution and textile material, resulting in change of textile material surface free energy. Electrokinetic phenomena, as zeta potential and specific amount of surface charge, characterize electric charge of textile material, while contact angle characterize its wettability. Cotton, as most of textile fibers, has electronegative charge in neutral and alkali water solution. Adsorption of dyestuffs, fluorescent whitening agents and other textile auxiliaries is not easy to perform due to existing repulsion forces. This can be overcome with large amount of electrolyte addition, what is economically and ecologically unfavorable. Therefore, alternative methods have been researched. One of them is cotton modification using amines and/or quaternary ammonium compounds which block negative OH groups resulting in electropositive cotton. This paper deals with interface phenomena of pretreated and modified cotton materials. For this purpose damask cotton fabric was desized, enzymatically and alkali scoured, bleached and mercerized in industrial conditions. Modification of cotton fabric for achieving electropositive charge was carried out by cationization before and during the mercerization process with cationic compound, quaternary ammonium salt – 3-chloro-2-hydroxypropyl-trimethyl ammonium chloride (CHPTAC). The effect of modification on the change of fabric zeta potential, surface free energy, contact angle, specific amount of surface charge, ionic surfactant and dyestuff adsorption ability were discussed. The zeta potential was measured by streaming current method on Electrokinetic analyzer, EKA depending on pH and surfactant addition. Isoelectric point, IEP and Point of Zero Charge, PZC were calculated from the results of zeta potential measurement. Contact angle was measured on DataPhysics OCA 20 Instrument using three different liquids – water, formamide and diiodomethane. From the results of disperse and polar components surface free energy was calculated. According to Chibowski method, wicking distance of polar and apolar solvents – water, formamide and n-heptane, components of surface free energy were calculated. The surface free energy calculated by different methods was discussed in a quantitative way. Adsorption of ionic surfactant with C12 – anionic Na-dodecyl sulphate (NDDS) and cationic Dodecyl trimethyl ammonium bromide (DDTMAB) was determined by potentiometric titration using using autotitrator Titrino (Metrohm). Qualitative evaluation of dyestuff adsorption was brought after dyeing with anionic dyestuff Benzopurpurin 4B (Sigma ; C.I. 2350 ; Direct Red 3) and measuring spectral characteristic using remission spectrophotometer Spectraflash 600 plus-CT (Datacolor). Additionally, the influence of cotton pretreatments on its mechanical properties has been investigated. It was shown that cationization during the mercerization process gives a new dimension of cotton pretreatment, as well as the quality assurance of cotton in the future.

Textile wettability and adsorption are the most important phases in textile finishing processes. These interface phenomena that occur at solid-liquid interface, like textile fabric and water solution, depend to a large extend on the kind and magnitude of the solid surface free energy. Changing the number of functional fiber surface groups, e.g. by pretreatment and modification of fabric, affect the distribution of surface charge, resulting in change of fabric surface free energy and wettability. Therefore, in this paper, plain woven cotton fabrics were enzymatically desized, enzymatically scoured with alkali and neutral pectinases, chemically bleached, mercerized and cationized during mercerization. The influence of these pretreatment processes and modifications to cotton fabric interface phenomena was investigated throughout the change of fabric surface free energy and contact angle. Contact angle was measured on DataPhysics OCA 20 instrument. Disperse and polar components of surface free energy were recalculated from contact angle measurements and according to Chibowski thin-layer method as well. The surface free energies were discussed in a quantitative way. It is well known the fabrics treated in wet conditions undergo some structural changes ; therefore the degree of polymerization, DP for cotton cellulose was determined as well as mechanical properties of pretreated and modified cotton fabrics.

Beside the vital and powerful role of sun in our everyday lives the overdose of UV radiation on skin can lead to potential skin damage from exposure to the sun's ray. Compare with visible light that interacts with dyes UV radiation interacts with ultraviolet absorbers and fluorescent whitening agents. Middle UV-rays (UV-B region,  =280-315 nm) causes acute and chronic reactions and damages such as skin reddening or increased risk for other diseases. For such reason it is important to protect the people from the ultraviolet radiation falling on garments and sun-screening textiles such as tends. The level of such protection of fabric depends of a large number of factors as the type of fibre, porosity, density, moisture, colour and FWA in the case of white textiles. In this paper cationized cotton fabric was treated with UV reactive absorber on the base of oxalanilide, Tinofast CEL, by exhaust method to improve the UV protection of fabric. For optical brightening three stilben derivates as fluorescence whitening agents (FWA) were used in wide concentration range. Remission spectrophoto-meter SF 600 PLUS CT (Datacolor) was used for measuring CIE whiteness and Yellowing Index according to DIN 6167 Description of yellowing of practically white or practically colourless materials. UV protection was determined through Ultraviolet protection factor (UPF) using transmission spectrophotometer Cary 50 Solarscreen (Varian) according AS/NZS 4399:1996 Sun Protective Clothing: evaluation and classification. The relative intensity of fluorescence was determined using Carl-Zeiss Fluorometer. The aim of the paper was to study the FWA's fluorescence changes of sun protected cationized white cotton fabric.

Selülozik liflerin boyanmasında reaktif, direkt, küp, naftol ve kükürtboyarmaddeleri ile pigment boyalar kullanılmaktadır. En fazla ve yaygınolarak kullanılan direkt ve reaktif boyarmaddeler, selüloz liflerinin vekarısımlarının boyanmasında ve basılmasında yaklasık % 50'lik bir payla enönemli boyarmadde sınıflarını olusturmaktadır. Direkt boyarmaddeler,uygulamasının kolay ve ucuz olması sebebiyle düsük yas haslıklarınaragmen, reaktif boyarmaddeler ise yüksek yıkama haslık özelliklerinedeniyle, pamugun boyanmasında kullanılan en önemli boyarmaddegrubudur. Ancak bu iki boyarmadde grubu genelde pamuk lifine karsı orta birafiniteye sahiptir. Bu afinite eksikliginin üstesinden gelmek için yüksekmiktarda tuz kullanılmasına ragmen fikse olmus boya miktarı düsüktür.Bununla birlikte, pamuklu kumasların direkt ve reaktif boyarmaddelerleboyanması bol miktarda enerji ve su gerektirmekte ve islem sırasında kirlilikyaratmaktadır. Bu nedenle daha ekonomik, daha ekolojik, daha etkin, dahaverimli ve daha kolay uygulanabilir yöntemlerin ortaya konulmasıamaçlanmaktadır.Pamuk boyamacılıgında kullanılan hemen hemen tüm boyarmaddelerboyama islemleri sırasında anyonik karakterdedirler. Bunun yanı sırapamugun sulu çözeltilerdeki negatif zeta (d) potansiyeli nedeniyle, anyonikboyarmaddelerin afinitesi oldukça düsmektedir. Hem reaktif hem de direktboyarmaddeler sulu çözeltide anyoniktirler. Basta direkt ve reaktifboyarmaddeler olmak üzere pamuk lifleri ile olan afinite eksikligini yenmekiçin bu proje kapsamında, lifleri modifiye ederek, pozitif yüklü halegetirilmesinde farklı kimyasallar denenerek, renk verimi ve çesitli haslıklaraetkisi incelenmistir.Anahtar kelimeler: Pamuk, katyoniklestirme, direkt boyarmaddeler,reaktif boyarmaddeler, fiksatör, Quat 188 Reactive, direct, vat, naphthol and sulphur dyestuffs and pigment dyesare used to dye cellulosic fibers. The reactive and direct dyestuffs are themost important dyestuffs with approximately %50 portion of the dyeing andprinting of the cellulosic fibers. In spite of their low fastness to washingproperties direct dyestuffs are one of the most important dyestuffs which areused in cotton dying because their implementation is cheap and easy.Reactive dyestuffs are the other important dyestuffs which are used in cottondying due to their high fastness to washing properties. However these twodyestuffs have an average affinity towards cotton fibers. In order to overcomethis lack of affinity high amount of salt is used. Despite the excess usage ofsalt the fixed amount of dyestuff is low. In addition to this plenty of energyand water is required during the dying process of cotton fabric with directand reactive dyestuffs and pollution is occurred because of this process. Dueto these reasons more economic, more ecologic, more effective, moreproductive and more practical methods are tried to be found.Most of the dyestuffs which are used in cotton dying have an anioniccharacter during dying processes. Furthermore the affinity of anionicdyestuffs is decreased because of the negative zeta (d) potential in aqueoussolution of cotton. Both of the reactive and direct dyestuffs are anionic inaqueous solution. Within this project (thesis) in order get over the lack ofaffinity of direct and reactive dyestuffs towards cotton fibers; fibers aremodified, different chemicals are used in order to gain positive charge andthe affects of these processes on color efficiency and different fastness areexamined.Keywords: Cotton, cationization, direct dyestuffs, reactivedyestuffs, fixative, Quat 188 229

In addition to some beneficial effects of UV radiation on skin this radiation may cause skin damage such as sunburn, allergies, skin aging and even skin cancer especially during the summer time. It is well known that garment provides some UV protection, but in most cases there are not enough its sun screening properties. Compared with visible light that interacts with dyes, UV radiation interacts with ultraviolet absorbers and fluorescent whitening agents (FWA), as well. To prevent harmful UV rays transmission, fabrics can be treated with different UV absorbers. In this paper the influence of FWA on UV protection of pretreated cotton fabric was investigated. For the purpose of better adsorption property cotton fabric was pretreated during mercerization with cationic compound following by chemical and optical bleaching and finally by treatment with UV absorber. Additionally, the influence of cotton pretreatments on its mechanical properties was investigated.

The objective of this study is to enhance the expression of a plasmid DNA for mesenchymal stem cells (MSC) by combination of 3-dimensional (3D) tissue engineered scaffolds and non-viral gene carrier. As a carrier of plasmid DNA, dextran-spermine cationic polysaccharide was prepared by means of reductive-amination between oxidized dextran and the natural oligoamine, spermine. As the MSC scaffold, collagen sponges reinforced by incorporation of poly(glycolic acid) (PGA) fibers were used. A complex of the cationized dextran and plasmid DNA of BMP-2 was impregnated into the scaffolds. MCS were seeded into each scaffold and cultured by a 3D culture method. When MSC were cultured in the PGA-reinforced sponge, the level of BMP-2 expression was significantly enhanced by the cationized dextran-plasmid DNA complex impregnated into the scaffold than by the cationized dextran-plasmid DNA complex in 2-dimensional (2D) (tissue culture plate) culture method. The alkaline phosphatase activity and osteocalcin content of transfected MSC cultured in the PGA-reinforced sponge were significantly higher compared with 2D culture method. We conclude that combination of cationized dextran plasmid DNA complex and 3D tissue engineered scaffold was promising to promote the in vitro gene expression for MSC.

Cotton fibers, like most textile fibers, are negative charged in neutral and alkali aqueous solutions. Dyestuffs, optical brighteners and finishing agents in aqueous solution have the same electrical charge as cotton, so adsorption processes are difficult due to repulsive forces. This paper studies adsorption properties of modified cotton. Modification of cotton yarns for achieving electropositive charge and better adsorption properties was carried out by cationization with cationic compound, quaternary ammonium salt in different stages of pretreatment. It is an alternative method for improving dyestuff and surfactant adsorption. Dyestuff adsorption ability and ionic surfactants adsorption ability were investigated.