As células solares poliméricas (PSCs) e diodos emissores de luz poliméricos (PLEDs) destacam-se dos seus análogos inorgânicos pela possibilidade de reduzir custo de fabricação, obtenção de dispositivos mais leves e flexíveis, maior liberdade no design e menor tempo de produção de dispositivos, devido à sua maior facilidade de processamento. Neste trabalho foram investigadas as mudanças nas propriedades fotofísicas, eletroquímicas e elétricas do poli[2,7-(9,9-dioctilfluoreno)-alt-4,7-bis(2,5-tiofeno)-2,1,3-benzotiadiazol] (PDBT) e seus derivados contendo grupos substituintes hexila no anel tiofeno. Este polímero conjugado é conhecido por seu potencial para aplicações em PSCs. Para tanto, três copolímeros, contendo diferentes concentrações de mero tiofeno substituído, foram sintetizados via reação de acoplamento de Suzuki. Usando técnicas adequadas, foram verificadas correlações entre o comportamento fotofísico, térmico e elétrico dos copolímeros e o teor de tiofeno substituído. Os materiais poliméricos sintetizados foram aplicados como camada ativa em PLEDs e PSCs. Em relação aos PLEDs, foi verificada baixa luminância e emissão de luz na faixa da cor laranja e cor verde. Além disso, diferentes efeitos, relacionados com a concentração de tiofeno substituído e as propriedades fotovoltaicas, foram identificados nas PSCs montadas. / Polymer Solar cells (PSCs) and polymer light-emitting diodes (PLEDs) draw attention from their inorganic analogues for the possibility of manufacturing cost reduction, more light and flexible devices, as well as the greater design freedom and shorter production time devices due to its easier processing. In this work, we investigated the changes in the photophysical, electrochemical and electrical properties from poly[2,7-(9,9-dioctylfluorene)-alt-4,7-bis(2,5-thiophene)-2,1,3-benzothiadiazole] (PDBT) that was caused by hexyl substituents introduction on the copolymer thiophene rings. This conjugated polymer system is known for its PSCs applications potential. Therefore, three copolymers, with different concentrations of substituted thiophene mere, were synthesized by Suzuki polycondensation. Using appropriate techniques, direct relationships were verified between the photophysical, thermal and electrical behavior from copolymers and substituted thiophene content. The synthesized polymeric materials were applied as active layer in PLEDs and PSCs. Regarding PLEDs, it was verified a low luminance and light emission in the range of orange and green colors. Furthermore, different effects, related to the substituted thiophene concentration and photovoltaic properties, were identified from mounted PSCs.

Made available in DSpace on 2017-07-20T12:40:21Z (GMT). No. of bitstreams: 1 FabioSantanaSantos.pdf: 4363488 bytes, checksum: 41a5d6b8fb73b9234813c167b1c4d075 (MD5) Previous issue date: 2013-10-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In this work, we sought to develop a methodology for the preparation of composite conductive polymer metal oxides for application in photovoltaic devices. The goal is the preparation of in-situ deposition of polymer and TiO2 oxide, in a single step by Electrochemical Synthesis of the substrates with architecture specially prepared for this. This study was divided into three stages, initially prepared molecules that give may give rise to monomers precursors of conjugated polymers derived from poly-p-phenylenevinylene PPV and polythiophene, groups attached to the aromatic ring of the polymer chain, the type (-O-(CH2) xCH3, X = 9 or 4), and the CN group. We conducted theoretical based on the DFT method (Density Functional Theory) and experimental studies of bromination reactions by different routes, using CCl4 as a solvent, AcOMe and aqueous HBr/KBr. We carried out the preparation of ZnO nanoparticles by hydrothermal route. In a second step was conducted in the preparation of a copolymer (DCN-PPV/PPV) to evaluate the effect of the CN group in the structure. Studies electrochemical synthesis of polymers and copolymers composite polymer/nanoparticulate (TiO2) and (ZnO) oxide in order to create a form of application and the construction of a prototype of a photovoltaic device. We tested two electrochemical systems a compound of acetonitrile (ACN) tetrafluoroborate tetrabutylammonium (TBABF4) for synthesis of polyfluorene (PF) and polybenzofluorene (PBF), we tested for this through the addition of (TiO2) and (ZnO). We also evaluated the electrochemical synthesis of polymer poly-p-phenylene (PPP), polythiophene (PT) and between them copolymer (PPP/PT) in the middle of boron trifluoride diethyl etherate (BFEE), this system is realized The addition of 1% distilled water. Finally, we performed a preliminary study on the application of composites PF and TiO2, MB-PPV and TiO2, synthesized electrochemically in photovoltaic devices made in accordance with the structure (anode/polymer pure or composite/cathode); also being investigated nanolayers influence of the metal insert (NCM) nanolayers in the case of gold, the structure of the device (anode/NCM/ polymer pure or composite/cathode). / Neste trabalho, buscou-se desenvolver uma metodologia para preparação de compósitos polímeros conjugados/óxidos metálicos para aplicação em dispositivos fotovoltaicos. O objetivo foi a preparação in-situ dos polímeros e deposição dos óxido de TiO2, através da síntese eletroquímica sobre os substratos com arquitetura especialmente preparadas para isso. O trabalho foi dividido em três etapas, inicialmente preparou-se moléculas que possam dar origem a monômeros precursores de polímeros conjugados, derivados do poli-p-fenilenovinileno PPV e do politiofeno com os grupos ligados ao anel aromático da cadeia polimérica, do tipo (-O-(CH2)xCH3, X=9 ou 4), e o grupo CN. Foram feitos estudos teóricos baseados em DFT (teoria do funcional de densidade), e experimentais de reações de bromação por diferentes rotas, utilizando como solvente o CCl4, AcOMe e solução aquosa de HBr/KBr. As nanopartículas de ZnO foram sintetizadas pela rota hidrotermal. Em uma segunda etapa foi realizada a preparação de um copolímero (DCN-PPV/PPV) para avaliar o efeito do grupo CN na estrutura. Estudos de síntese eletroquímica de polímeros, copolímeros e compósitos polímero/nanoparticulas de óxido de TiO2 e ZnO, também foram realizados, com o intuito de criar uma forma de aplicação destes na construção de um protótipo de dispositivo fotovoltaico. Foram testados dois sistemas eletroquímicos, um composto por acetonitrila (ACN) e tetrafluoroborato de tetrabutilamonio (TBABF4), para síntese do polifluoreno (PF) e o polibenzofluoreno (PBF), e testou-se para este meio a adição de nanopartículas de oxido de titânio TiO2 e de zinco ZnO. Avaliou-se também a síntese eletroquímica dos polímeros poli-p-fenileno (PPP), politiofeno (PT) e o copolímero entre eles (PPP/PT) em meio de trifluoreto de boro dietil eterato (BFEE). Por fim, foi feito um estudo preliminar sobre a aplicação dos compósitos PF/TiO2 e MB-PPV/TiO2, sintetizados eletroquimicamente em dispositivos fotovoltaicos confeccionados de acordo com a estrutura (ânodo/polímero puro ou compósito/Cátodo); sendo também investigada a influência da inserção de nanocamadas metálicas de ouro (NCM), na estrutura do dispositivo (ânodo/NCM/polímero ou compósito/cátodo).

Transthyretin (TTR) amyloidosis is a disease that appears in three variants. One variant affects the elderly population with heart failure, the other two variants are hereditary and caused by an amino acid substitution in the gene, resulting in polyneuropathy and/or heart issues depending on the amino acid substitution. However, in all three variants, other organs may also be affected with amyloid deposition in the disease course. Amyloid fibrils of TTR (ATTR) contains a mixture of full-length protein and fragments (50-127). Luminescent conjugated oligothiophenes (LCO’s) are novel amyloid binding probes used to stain amyloid fibrils and these amyloid probes have the feature of characterizing the amyloid structure in terms of fluorescence spectra. Apart from LCO’s, a few other amyloid binding probes are used to stain recombinant amyloid transthyretin and native transthyretin for binding studies. The majority of generated TTR aggregates in vitro did not have the characteristic fluorescence spectra when bound to LCO’s and was observed as a clumped gel-like aggregate. The generation of recombinant TTR fibrils in vitro using the mutant TTR-T49M to obtain an aggregation prone fragment (50-127) after being treated with cyanogen bromide had a low yield of in vivo amyloid-like fibrils, but with characteristic LCO spectra. Carpal tunnel ATTR often precedes ATTR deposition in heart tissue. Amyloid transthyretin in carpal tunnel tissues was stained with LCO’s and used as a reference in the comparison against the in vitro generated recombinant amyloid transthyretin fibrils. This project also includes quantification of amyloid transthyretin in a few selected parts of the carpal tunnel tissue using ImageJ. In the long run this method could help in diagnosing TTR amyloidosis.

Le tissu adipeux blanc (TA) joue un rôle central dans la physiopathologie de l'obésité et la résistance à l'insuline. Durant ma thèse, j’ai étudié la réponse cellulaire et moléculaire du TA au stress métabolique induit chez la souris par l'administration d'un isomère de l'acide linoléique (CLA). Nous avons utilisé l’isomère trans10,cis12 de l'acide linoléique (t10,c12-CLA) pour promouvoir un syndrome lipoatrophique chez la souris C57BL/6J. La dynamique de cette réponse a été explorée dans le TA, l'intestin et au niveau systémique, sur deux périodes consécutives de 7 jours d’administration de t10,c12-CLA puis d’interruption du traitement. Nos résultats montrent que t10,c12-CLA induit une dérégulation des gènes métaboliques et un dépôt de matrice extracellulaire (ECM) dans le TA. Le profil immunologique est perturbé, avec l'accumulation de macrophages M2 anti-inflammatoires. Ces altérations métaboliques, immunitaires et structurelles sont inversées, mais pas toujours normalisées, après 7 jours de récupération. La réversibilité des modifications observées dans le TA indique que cette réponse est plus adaptative que pathologique. Cependant, les altérations induites par t10, c12-CLA dans le TA sont temporellement liées à l'hyperinsulinémie, ce qui renforce l’idée que l'intégrité du TA est cruciale pour l'homéostasie glucidique. Bien qu’aucune réponse immunitaire n’ait été observée dans l'intestin, l’expression des gènes codant pour des protéines de jonctions serrées (claudine et occludine) est diminuée. Une partie des effets de t10,c12-CLA pourrait être relayée par l’augmentation de la perméabilité intestinale. Cette étude montre que, en réponse à un stress nutritionnel de courte durée, le TA regagne rapidement son homéostasie. Lorsque la contrainte est plus chronique, comme dans l'obésité, la plupart des interventions ne parviennent pas à inverser l'état dysfonctionnel du TA. Le grand défi dans les années à venir reste de trouver des stratégies thérapeutiques à long terme dans les maladies métaboliques. / White adipose tissue (WAT) plays a central role in the physiopathology of obesity and insulin resistance. During my PhD, I studied the cellular and molecular response of WAT to metabolic stress induced in mice by the administration of an isomer of linoleic acid (CLA). We used trans10,cis12 isomer of linoleic acid (t10,c12-CLA) as a tool to promote a lipoatrophic syndrome in C57BL/6J lean female mice. The short-term dynamics of this response was explored in WAT, gut and at systemic level, over two consecutive 7-day periods of t10,c12-CLA administration and withdrawal. Our results show that t10,C12-CLA-induced alterations in WAT included metabolic gene deregulation and extracellular matrix deposition. The immunological profile of WAT was markedly disturbed, with anti-inflammatory M2-polarized macrophage accumulation. Metabolic, immune and structural alteration were fully revered, but not always normalized after 7 days without treatment. The reversibility of WAT alterations indicates a more adaptive than pathological response to t10,C12-CLA. However, t10,c12-CLA-induced WAT deregulation is temporally linked to hyperinsulinemia supporting the primacy of WAT integrity for glucose homeostasis. No immune alteration was observed in response to t10,C12-CLA in the gut, where genes encoding tight junction proteins (claudin and occludin) were down regulated. Thus, part of the effects of t10,c12-CLA could be mediated by increased intestinal permeability. This study shows that in response to an acute nutritional stressor, WAT and glucose homeostasis could be rapidly regained. When the stress is more chronic, as in obesity, most of the interventions fail to reverse WAT dysfunctional state, underlining the big challenge in the years ahead of finding long-term therapeutic strategies in metabolic diseases.

O ácido linoléico conjugado (CLA) é um ácido graxo poliinsaturado, encontrado nos produtos da alimentação. Estudos indicam que o CLA possui ações contra câncer, aterogênese e DM 2 e obesidade. O presente trabalho avaliou os efeitos da suplementação crônica com CLA em ratos Wistar machos e teve como objetivo investigar o desenvolvimento corporal e o perfil metabólico dos animais e dos adipócitos isolados do tecido adiposo branco periepididimal. Após quatro semanas de suplementação os animais apresentaram redução no ritmo de ganho de peso, acompanhado de redução da ingestão alimentar, redução da massa adiposa e do volume celular dos adipócitos. A menor incorporação dos substratos acetato e glicose em lipídeos, o aumento lipólise e diminuição da expressão do PPAR?, também contribuíram para menor adiposidade encontrada. A redução de massa adiposa foi acompanhada por resistência à insulina, elevados níveis de citocinas inflamatórias e desenvolvimento de esteatose hepática. Esses fatores estão relacionados com o desenvolvimento de síndrome lipodistrófica em animais. Portanto, a efetividade do CLA em reduzir massa adiposa foi comprovada no presente estudo, mas os efeitos devem ser considerados. / Conjugated linoleic acid (CLA) is a natural polyunsatured fatty acid found in many dietary sources. Animal studies demonstrated that CLA has properties against cancer, atherogenesis, diabetes and obesity. This work evaluated the effects with chronic CLA supplementation in young adults Wistar male rats for four weeks, aiming to investigate the possible changes in corporal development and metabolic profile as well as the effects in isolated adipocytes of periepidydimal white adipose tissue of these supplemented animals. We observed a reduction of the rhythym of body weight gain, followed by diminished food intake, regression of adipose mass, and also a reduction of adipocyte volume. The findings of low incorporation of acetate and glucose substrates into lipids, elevation on the lipolytic response and reduction of PPAR-gamma gene expression, also contributed to the lower adiposity. This reduction in adipose mass was followed by insulin resistance, high levels of inflammatory citokines and the development of hepatic steatosis, features related to the development of lipodystrophic syndrome. Therefore, this study demonstrated the CLA effect on reduction of adipose mass, although adverse effects associated with CLA chronic supplementation must be considered.

Os objetivos deste experimento foram os de realizar levantamento exploratório da produção, composição e perfil de ácidos graxos do leite de búfalas e dos alimentos utilizados em cinco fazendas da região de Sarapuí e Pilar do Sul, no Estado de São Paulo. Foram coletadas amostras mensais de leite de oito búfalas por fazenda e de alimentos durante os meses de abril a novembro de 2002. Das cinco fazendas, uma explorava sistema de confinamento total e quatro usavam sistemas de produção a pasto com suplementação volumosa no inverno (silagem de gramíneas e cana-de-açúcar) e concentrado (resíduo de cervejaria ou mistura comercial) o ano todo.Três propriedades realizavam duas ordenhas diárias, e as demais apenas uma. Os teores de gordura, proteína e lactose variaram de 5,4 a 8,6%, 3,7 a 4,9% e 4,5 a 5,6%, respectivamente, valores normais para bubalinos. Os teores de gordura e de proteína aumentaram ao longo da lactação, enquanto o teor de lactose acompanhou a curva de lactação. O teor de nitrogênio uréico no leite variou entre 5,6 e 27,3 mg/dL, com valor médio em todas as fazendas de 15,9 mg/dL, inferior ao observado na literatura para bubalinos. Do total de ácidos graxos na B. decumbens o ácido linoléico variou de 18,2% no inverno para 19,9% no verão e o ácido linolênico de 20,8% no inverno para 31,4% no verão. A B. ruziziensis apresentou teor de ácido linoléico 17,7% no inverno e 19,4% no verão, enquanto o ácido linolênico variou de 50,2% no inverno para 45,6% no verão. Observou-se grande variação individual no teor de CLA no leite de bubalinos (0,31-3,42%). Nos animais a pasto ou com suplementação volumosa de gramíneas frescas a variação foi maior (0,44 a 3,31%) que nos animais confinados (0,31 a 1,74%). Os teores obtidos de CLA no verão foram em média mais elevados (38,6%), que no inverno, nos rebanhos em pastejo. A Análise de Componentes Principais confirmou a correlação positiva entre os ácidos graxos de cadeia ímpar e de cadeia ramificada e alta correlação entre os ácidos capróico, caprílico e cáprico. Também indicou correlação negativa entre os ácidos graxos de cadeia longa com os de cadeia curta, média, ímpar e ramificada. O teor dos ácidos graxos hiper-colesterolêmicos (ácidos láurico, mirístico e palmítico) diminuiu à medida que houve elevação do teor de ácidos graxos de cadeia longa no leite. A atividade da enzima ∆9-dessaturase, medida indiretamente (relação produto x substrato), foi maior em animais que receberam resíduo de cervejaria em menor quantidade ao longo do ano. / The objective of this study was to determine milk production, composition and fatty acids profiles in five buffalo farms in the Sarapui and Pilar do Sul counties, in the Southeast region of the State of Sao Paulo. Monthly feed and milk (from eight animals per farm) samples were collected from April to November 2002. In one farm animals were housed in total confinement and were fed a TMR ration; wet brewers grains and a commercial grain mix and summer pasture and a mixture of grass silage plus chopped sugar cane during winter were offered in the remaining farms. Animals were milked twice daily in three farms. Milk fat, protein and lactose contents varied from 5.4 to8.6%, 3.7 to 4.9% and 4.5 to 5.6%, respectively. Milk fat and protein contents increased as the lactation progressed. Milk urea nitrogen showed a large variation among farms (5.6 to 27.3 mg/dL). The content of linoleic and linolenic acids in B. decumbens varied from18.2 and 20.8% (winter) to 19.9 and 31.4% (summer) and in B. ruziziensis varied from 17.7 and 50.2% (winter) to 19.4 and 45.6% (summer). "Milk CLA content showed a large variation among animals (0.31 to 3.42%). Pasture fed or green chopp supplemented animals showed a larger variation (0.44 to 3.31%) than TMR fed animals (0.31 to 1.74%). Milk CLA content was higher (39%) during summer than in winter, in pasture fed animals. Principle Component Analysis confirmed the positive correlation between odd chain and side chain fatty acids and a high correlation among caproic, caprilic and capric acids. It also showed a negative correlation between long chain fatty acids and short and medium chain and odd and side chain fatty acids. Milk hiper-colesterolemic fatty acids (lauric, miristic and palmitic acids) content decreased as the long chain fatty acids did increased. The indirectly measured Delta 9 dessaturase activity was higher in animals being offered small amounts of wet brewers grains throughout the lactation.

Le couplage covalent de précurseurs moléculaires spécialement conçus, assisté par une surface métallique, a récemment émergé comme nouvelle voie pour la création de nouvelles architectures moléculaires prometteuses pour l’électronique moléculaire. Les phtalocyanines et leurs dérivés ont attiré beaucoup d’intérêt à cause de leurs propriétés chimiques et optoélectroniques. Dans cette thèse la synthèse de composés de phtalocyanine est présentée. Les composés sont obtenus par une réaction en surface entre précurseurs fonctionnalisés avec quatre groupements carbonitriles et des atomes métalliques. L’étude expérimentale est faite par microscopie à effet tunnel et spectroscopie de photoémission X. Les précurseurs moléculaires de TCN-DBTTF et de PPCN ont été étudiés. Les TCN-DBTTF ont été déposés avec les atomes de Mn, Fe ou Cu sur Ag(111) et Au(111). La réaction de cyclotetramerization a été activée par recuits. Dans le cas le plus favorable (TCN-DBTTF avec Fe sur Ag(111)), la réaction peut être activée à 200°C et permet la synthèse de phtalocyanines individuelles. Un recuit à plus haute température permet de continuer la réaction en 1D (250°C) et en 2D (275°C). Des résultats similaires ont été obtenus pour le dépôt de PPCN avec Mn ou Cu sur Au(111). L’évolution des spectres des niveaux de coeur permet d’obtenir une preuve de la réaction. Les différents facteurs qui influencent la cyclotetramerisation ont été étudiés.L'étude démontre la versatilité de la méthode: la synthèse en surface permet la création de polymères 2D originaux connectés par des macrocycles de phtalocyanine susceptibles d’être étendus à un grand nombre de précurseurs et d’atomes métalliques. / Surface-assisted covalent coupling of suitably designed molecular precursors on metal surfaces has recently emerged as a new route towards the design of novel molecular architectures promising for future applications. Phthalocyanines and their derivatives have been widely studied for their chemical and optoelectronic properties. In this thesis the synthesis of phthalocyanine compounds is presented. The compounds are obtained through an on-surface reaction between tetracarbonitrile-functionalized precursors and metals. The experimental investigation is carried out by means of scanning tunnelling microscopy and X-Ray photoemission spectroscopy. Two molecular precursors, TCN-DBTTF and PPCN, are studied. TCN-DBTTF molecules are deposited with metal atoms (Mn, Fe, or Cu) on Ag(111) and Au(111). Annealing is used to activate the reaction of cyclotetramerization between precursors and metals. In the most favourable case (TCN-DBTTF with Fe on Ag(111)) the reaction can be activated at 200°C and leads to the synthesis of individual phthalocyanines. Increasing the temperature allows the synthesis of polymeric lines, at 250°C, and small 2D domains, at 275°C. Similar results are obtained for PPCN deposition with Mn or Cu on Au(111). In this latter case, the evolution of core level spectra allows a chemical proof of the on-surface reaction. The factors affecting on-surface cyclotetramerization have also been studied. This study demonstrates the versatility of the method: on-surface cyclotetramerization allows creating original 2D polymers connected by phthalocyanine macrocycles, and may work with a wide range of tetracarbonitrile-functionalized precursors and metallic atoms.

Small fluorescent probes are important tools when studying protein aggregates involved in different neurodegenerative diseases, such as Alzheimer’s disease. Luminescent conjugated oligothiophenes have been developed and shown to be excellent ligands when studying morphology among amyloids, due to their conjugated thiophene backbone that provides them with unique photophysical properties. This kind of probes are being developed successively to enhance the specificity of their biological targets. In this project, luminescent conjugated oligothiophenes functionalized with amino acids, so called proteophenes, have been synthesized to investigate their optical properties. Since amino acids are chiral molecules, the possibility of induced chirality to the thiophene backbone was examined, as well as the proteophenes ability to work as amyloidospecific ligands for the study of protein aggregates. The synthesis of four different proteophenes are presented in this report, along with analysis results of their photophysical properties.

The main focus of this thesis is on the aromaticity of the ground state and electronically excited states of π-conjugated molecules and polymers, as well as how aromaticity is connected to their properties. The electronic structures of polybenzenoid hydrocarbons (PBHs) were explored through density functional theory (DFT) calculations and the π-component of the electron localization function (ELFπ). The study revealed how the π-electronic structure is influenced by the fusion of double bonds or benzene rings to the PBHs. We also demonstrated that the π-electrons of benzene extend to accommodate as much aromaticity as possible when bond length distorted.   The aromatic chameleon property displayed by fulvenes, isobenzofulvenes, fulvalenes, bis(fulvene)s, and polyfulvenes were investigated using DFT calculations. The tria-, penta-, and heptafulvenes were shown to possess ionization energies and electron affinities which can be tuned extensively by substitution, some of which even outperform TTF and TCNQ, the prototypical electron donor and acceptor, respectively. The singlet-triplet energy gap of pentafulvenes can be tuned extensively by substitution to the point that the triplet state is lower than the singlet state and thus becomes the ground state. The ELFπ of isobenzofulvene shows that the benzene ring in an electronically excited state can be more aromatic than the corresponding ring in the ground state. We have shown that the 6-ring of [5.6.7]quinarene is influenced by a Hückel aromatic resonance structure with 4n+2 π-electrons in the excited quintet state. The bis(fulvene)s which are composed of a donor type heptafulvene and an acceptor type pentafulvene, retain the basic donor-acceptor properties of the two fragments and could function as compact donor-acceptor dyads. A few of the designed polyfulvenes were found to have band gaps below 1 eV at the PBC-B3LYP/6-31G(d) level. Various 2,7-disubstituted fluorenones and dibenzofulvenes were synthesized and their excited state properties were investigated by absorption spectroscopy and time-dependent DFT calculations. It was found that the 1A → 1B transition of ππ* character can be tuned by substitution in the 2,7-positions. The 2,7-bis(N,N-dimethyl) derivatives of fluorenone and dibenzofulvene displayed low energy transitions at 2.18 and 1.61 eV, respectively, in toluene.

Label-free detection of DNA has been successfully demonstrated on field effect transistor (FET) based devices. Since conducting organic materials was discovered and have attracted more and more research efforts by their profound advantages, this work will focus on utilizing an organic field effect transistor (OFET) as DNA sensor. An OFET constructed with a transporting fluidic channel, WetOFET, forms a fluid-polymer (active layer) interface where the probe DNA can be introduced. DNA hybridization and non-hybridization after injecting target DNA and non-target DNA were monitored by transistor characteristics. The Hysteresis area of transfer curve increased after DNA hybridization which may be caused by the increasing electrostatic screening induced by the increasing negative charge from target DNA. The different morphology of coating surface could also influence the OFET response.