Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2016-12-02T12:49:44Z No. of bitstreams: 1 PDF - Yuri Basílio Gomes Patriota.pdf: 955612 bytes, checksum: 03ba9e97932ba281d6427913b6fc9361 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-12-06T19:13:13Z (GMT) No. of bitstreams: 1 PDF - Yuri Basílio Gomes Patriota.pdf: 955612 bytes, checksum: 03ba9e97932ba281d6427913b6fc9361 (MD5) / Made available in DSpace on 2016-12-06T19:13:14Z (GMT). No. of bitstreams: 1 PDF - Yuri Basílio Gomes Patriota.pdf: 955612 bytes, checksum: 03ba9e97932ba281d6427913b6fc9361 (MD5) Previous issue date: 2015-08-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Microemulsions (MEs) are isotropic and thermodynamically stable systems translucent two immiscible liquids, usually water and oil, stabilized by an interfacial film of surfactants located at the oil / water interface. The thiophenes and its derivatives are an important class of heterocyclic compounds having a wide variety of biological properties including antibacterial, antifungal, analgesic, anti-inflammatory, antioxidant. In this study 2 - [(2,4-dichloro-benzylidene)-amino]-5,6-dihydro-4H- cyclopenta [b] thiophene-3-carbonitrile was utilized, called 5CN06. The objective of this research was to develop, characterize and evaluate the in vitro antifungal activity of microemulsion for oral use containing a thiophene derivative. A pseudo-ternary phase diagram (PTPD) was constructed adopting a high energy approach using labrasol (LAS) as surfactant, Ethanol (EtOH) as co-surfactant, isopropyl myristate (IPM) as oil phase and water as aqueous phase. Proportions defined of LAS, IPM and EtOH were titrated with water and the appearance observed at each point of DFPT and the ME regions were highlighted. The blank ME (ME B) was obtained from a selected point in DFPT, at this point it was evaluated the incorporation of 5CN06 by three different methods (M1, M2 and M3). All formulations were characterized and evaluated for macroscopic aspects, entrapment efficiency, droplet size and polydispersity index (PDI), polarized light microscopy, differential scanning calorimetry (DSC), X-ray diffraction (XRD) and in vitro antimicrobial activity. A spectrophotometric analytical method was developed and validated to quantify the 5CN06 in MEs. The technique employed for the construction of PTPD proved quite simple and reproducible. The MEs maintained clarity, transparency and isotropy after incorporation of 5CN06. Blank ME (ME B) and three incorporated ME (ME M1, ME M2 and ME M3) showed droplets sizes with diameter of 24.8 ± 0.5 nm, 25.5 ± 0.42 nm, 24.3 ± 0.43 nm and 29.7 ± 2.5 nm with PDI of 0.371 ± 0.013, 0.377 ± 0.009, 0.362 ± 0.020 and 0.354 ± 0.013 and 5CN06 entrapment of 84%, 86% and 88%, respectively. The MEs formulations were physically stable by storage for 30 days under stress conditions. The analytical method developed and validated showed simple, fast and with minimal cost being considered linear, specific, accurate and precise and therefore validated according the International Conference on Harmonization (ICH) and National Health Surveillance Agency (ANVISA). Previously the antimicrobial activity assay, the 5CN06 was quantified in MEs systems and the results showed that the concentration of 5CN06 was 57, 117,5 and 133,1 for ME M1, ME M2 and ME M3, respectively. ME M2 and M3 showed higher concentration and it were utilized for further studies. Antimicrobial activity of ME M2 and M3 was -1 evaluated and minimal inhibitory concentration (MIC) of 29.4 μg.ml to -1 Staphylococcus aureus and 3.7 μg.ml for both yeasts C. tropicalis e C. parapsilosis -1 were obtained for ME M2. To ME M3 were obtained MIC of 66.6 μg.ml for both -1 strains, Staphylococcus aureus e Escherichia coli and 4.2 μg.ml for Candida albicans, C. tropicalis e C. guillermondii. This preliminary data indicate the potential of MEs for oral delivery of poor aqueous solubility drugs. / Microemulsões (MEs) são sistemas termodinamicamente estáveis e isotropicamente translúcidos de dois líquidos imiscíveis, usualmente água e óleo, estabilizados por um filme interfacial de tensoativos localizados na interface óleo/água. Os tiofenos e seus derivados são uma importante classe de compostos heterocíclicos que possui uma grande variedade de propriedades biológicas tais como antibacteriana, antifúngica, analgésica, anti-inflamatória e antioxidante. Nesse estudo, foi utilizado o 2-[(2,4-dicloro-benzilideno)-amino]-5,6-diidro-4H-ciclopenta [b] tiofeno-3-carbonitrila, denominado de 5CN06. O objetivo desse trabalho foi desenvolver, caracterizar e avaliar a atividade antifúngica in vitro de microemulsões para uso oral contendo um fármaco derivado do tiofeno (5CN06). Diagramas de fases pseudoternário (DFPT) ® foram construídos usando labrasol (LAS) como tensoativo, etanol (EtOH) como co- tensoativo, miristato de isopropila (MIP) como a fase oleosa e água como a fase aquosa. Proporções definidas de LAS, EtOH e MIP foram tituladas com água e o aspecto observado em cada ponto do DFPT e as regiões de ME foram destacadas. A ME branca (ME B) foi obtida a partir de um ponto selecionado no DFPT, e a esse ponto avaliou-se a incorporação do 5CN06 por três métodos distintos (M1, M2 e M3). Todas as formulações foram caracterizadas e avaliadas quanto aos aspectos macroscópicos, eficiência de encaspulação, tamanho de gotícula, índice de polidispersão (IPD), microscopia de luz polarizada, calorimetria exploratória diferencial (DSC), difração de raios – X (DRX) e atividade antimicrobiana in vitro. Um método analítico espectrofotométrico foi desenvolvido e validado para quantificação do 5CN06 nas MEs. A técnica empregada para a construção do DFPT se mostrou bastante simples e reprodutível. As MEs mantiveram limpidez, transparência e isotropia após a incorporação do 5CN06. A ME B e as formulações ME M1, M2 e M3 apresentaram tamanhos de gotículas com diâmetro de 24,8 ± 0,5 nm, 25,5 ± 0,42 nm, 24,3 ± 0,43 nm e 29,7 ± 2,5 nm com IPD de 0,371 ± 0,013, 0,377 ± 0,009, 0,362 ± 0,020 e 0,354 ± 0,013 e eficiência de encapsulação de 84%, 86% e 88%, respectivamente. As formulações foram fisicamente estáveis por 30 dias sob armazenamento em condições de estresse. O método analítico desenvolvido e validado se mostrou simples e rápido, sendo considerado linear, específico, exato e preciso e, portanto, validado de acordo com os critérios da International Conference on Harmonization (ICH) e da Agência Nacional de Vigilância Sanitária (ANVISA). Previamente ao estudo da atividade antimicrobiana, o 5CN06 foi quantificado em -1 todos os sistemas e os resultados mostraram 57, 117,1 e 133,1 μg.ml para a ME M1, M2 e M3. As MEs M2 e M3 mostraram as maiores concentrações e foram utilizadas para os estudos posteriores. A atividade antimicrobiana das MEs M2 e M3 -1 foi avaliada e valores de concentrações inibitórias mínimas (CIMs) de 29.4 μg.ml -1 para Staphylococcus aureus e 3.7 μg.ml para ambas as leveduras, C. tropicalis e C. parapsilosis, foram obtidas para ME M2. Para a ME M3, foram obtidos CIM de -1 66.6 μg.ml para ambas as cepas Staphylococcus aureus e Escherichia coli e 4.2 -1 μg.ml para Candida albicans, C. tropicalis e C. guillermondii. Estes dados preliminares indicam o potencial das microemulsões na utilização de fármacos com baixa solubilidade aquosa pela via oral.

Morphological architecturing is one of the smart and efficient ways to maximize the number of excitons harvested from the known photoactive materials and existing fabrication technologies. Surfaces and interfaces play a vital role in absorbing light and therefore when patterned regularly, aid in the improvement of light absorption. This thesis deals with the study of light management by morphologically architecturing the organic electroactive materials. Here, morphological architecturing is carried out using electrospinning technique by optimizing various parameters. In the first part, organic photovoltaic system is tailored by morphologically modifying the conjugated polymer active layer and analyzing the enhancement in light collection and hence performance of photovoltaic devices. In the second part, the prospects of using free standing buffer layer instead of thin film buffer layer in a solar cell is evaluated. Furthermore, the study on morphological engineering of conjugated small molecule is carried out, by varying the solvents and derivatives, in order to control morphologies by understanding the underlying mechanism. Overall this thesis attempts to understand the fundamentals in morphological architecturing, by physical architecturing of the small molecules in a device for light management applications as well as demonstrating improvement in light absorption in existing organic photovoltaic systems. In the introduction chapter, a brief description of organic photovoltaics is given followed by highlighting the importance of processing methods in light management and in organic photovoltaics. The significance of structured architecture in improving the device characteristics is presented. The issues and challenges in existing architecturing techniques available in literature are discussed. Electrospinning as a tool for morphological modification for organic photovoltaics is demonstrated. This is followed by an outline of the thesis. In Chapter 2, brief description of procedures carried out for fabrication, characterization and optimization of electrospinning process parameters are discussed. The description of fabrication procedures including electrospinning, spincoating and thermal evaporation are given. Characterization techniques used in this thesis for surface and feature analysis, structural, compositional, optical and opto-electrical analyses are described. Optimization of electrospinning process parameters in obtaining various morphologies are evaluated. In Chapter 3, enhancement of device characteristics of poly (3-hexylthiophene): phenyl C61-butyric acid methyl ester (P3HT: PCBM) by changing active layer film morphology into network structure is elucidated. Network structure is provided by electrospraying assisted hierarchical assembly of short fibrils. Effect of electrospraying parameters such as solvent, polymer blend concentration, applied voltage, tip to collector distance, flow rate and deposition time are analyzed. Solvent and applied voltage are observed to be the major parameters governing the formation of network structure. The optimized conditions are used to investigate the optical and structural properties. Percent reflectance studies showed improvement in light absorption due to increase in surface area. Structural characterization studies indicate an increase in orientation of crystallites and crystallinity as compared to spincoated samples. The optimized conditions along with additional spincoated layer of P3HT:PCBM are used to fabricate bulk heterojunction device. Device characteristics exhibited an increase in short circuit current and thus increase in efficiency from 2.18% to 3.66%. There is a enhancement of 37.5% going from maximum external quantum efficiency of 40%-55% for electrosprayed and spincoated devices. It is anticipated that network morphology could be the next possible structure to be explored in organic photovoltaic materials. In Chapter 4, photonic structure is analyzed and compared. A photonics device requires uniform periodic structural arrangement. Various techniques are used to fabricate these types of structures, employing several steps of fabrication. This work proposes single step hierarchical array of equal submicron size porous structure fabricated by tuning electrospinning processing parameters. The dictating process parameters on evolving structure are high voltage, tip to collector distance and solvent. Morphological and optical investigations suggest that uniform periodic topography helps in light scattering leading to multi reflection and thus enhancement in light absorption. This structure is evaluated as active layer in organic photovoltaic devices using poly (3 hexyl thiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) blend and its device characteristics are analyzed. Consistent and reliable device characteristics obtained through photonic structure is demonstrated. Finally, comparison is drawn to network structure to assess the advantages and limitations of both morphologies as active layer in organic photovoltaics. In Chapter 5, instead of architecturing active layer the next polymer film layer in the organic solar cells, that is the hole transport layer is transformed into free standing nanofiber mats. Morphological, structural and surface wetting properties are assessed for these nanofiber mats followed by fabrication of inverted organic solar cell. The free standing nanofibers mats are obtained by electrospinning the blend of Poly(3,4-ethylenedioxythiophene) Polystyrene sulfonate (PEDOT:PSS) a conducting water soluble polymer with other water soluble polymers such as poly vinyl alcohol (PVA) and poly ethylene oxide (PEO). The study is further extended by employing two batches of PEDOT:PSS of varying conductivity that are analyzed side by side for six ternary and two binary blends each. Electrospinning parameters such as applied voltage and flow rate are optimized and fibers of diameter 150-200 nm are obtained. Maximum content of PEDOT:PSS with which free standing fiber mats could be achieved are 98 and 99%. Subsequent increase in PEDOT:PSS results in formation of beads. Surface wetting behavior showed that hydrophillicity increases with increase in PEDOT:PSS content. Devices are fabricated and the variation in characteristics and charge collection with respect to addition of PEO and PVA are discussed. In Chapter 6, a conjugated small molecule is taken as case study unlike the use of the conjugated polymer studies in previous chapters. A mechanism is proposed for tuning the sphere-spike morphology and also to control the crystallite size through solvent management using a conjugated small molecule. Electrospraying of an organic molecule is carried out using various solvents, obtaining fibril structures along with a range of distinct morphologies. Solvent characteristics play a major role in achieving the morphology of the organic material. A thiophene derivative (7, 9-di (thiophen-2-yl)-8H-cyclopenta [a]acenaphthylen-8-one) (DTCPA) of donor-acceptor-donor (DAD) architecture is used to study this solvent effect. Seven solvents with decreasing vapor pressure are selected for experiments. Electrospraying is conducted at a solution concentration of 1.5 wt % and a constant applied voltage of 15 kV. Gradual transformation in morphology of the electrospun product from spikes-sphere to only spikes is observed. A mechanism describing this transformation is proposed based on the electron micrograph analysis and XRD analysis. These data indicate that the morphological change is due to the synergistic effect of both vapor pressure and dielectric constant of the solvents. Through a reasonable control over the crystallites size and morphology along with supporting transformation mechanism theory, the work in this chapter elucidates electrospraying as a prospective method for designing the architectures in organic electronics. In Chapter 7, light management studies are carried out by morphologically architecturing the carbazole derivatives through electrospraying. The effect of derivatives on morphology is analyzed. The two carbazole derivatives; carbazole-benzothiadiazole (Cz-Bz) resulted in 2D structures and carbazole-benzothiadiazole-bithiophene (Cz-Bz-Bt) resulted in 3D structures after electrospraying. These structures are further analyzed to study the effect of vapor pressure of solvents and solution concentration. Structural characteristics indicate that electrospraying imparts change in molecular structure orientation. Optical studies showed 19 – 31% enhancement in light absorption. Further, three types of organic photovoltaic devices are fabricated and the opto-electrical properties are evaluated. Also, the effect of substrate on morphological formation is assessed. In Chapter 8, the major contributions and conclusions drawn from the morphological architecturing of both conjugated polymers and small molecules are summarized, along with few recommendations for future research.

Made available in DSpace on 2015-05-14T12:59:49Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2233780 bytes, checksum: 36fd18af67f2bd8e2c76af844131f20c (MD5) Previous issue date: 2012-08-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Heterocyclic compounds are the biggest sources of synthetic drugs and have grown exponentially with important applications in the pharmaceutical industry. Amongst the heterocyclic compounds, it has been highlighted the thiophenes category and its derivatives, which call attention for presenting important pharmacological actions, especially analgesic and the anti-inflammatory ones. The present study aims to investigate the Antinociceptive, anti-inflammatory activity and acute pre-clinical from tiophenic derivative 6CN10. The behavioral pharmacological screening of treated animals (250, 500 and 1000 mg/kg) showed changes, such as analgesia and ambulation reduction. There was no death of animals or the presence of toxic signs. From the pharmacological screening was determined the use of three doses (25, 50 and 100 mg/kg) for other studies. In the Rota rod and open field tests, there were no changes in the motor coordination of animals, discarding the possibility of a myorelaxant effect. Through models of nociception inducers, such as the abdominal constriction induced by acetic acid, formalin and hot plate, it was noticed a dose-dependent Antinociceptive activity of 6CN10. Such effect did not show itself to be associated to the opioid via of central analgesia, once this derivative did not produce any significant effect in the hot plate test, and because it has not been blocked by naloxone, an pattern antagonist opioid. The 6CN10 inhibited significantly the time of paw licking in both phases of the formalin test, especially at the inflammatory phase, being needed an analysis of the anti-inflammatory activity of the derivative. For this purpose, it was used the model of induced peritonitis by carrageenan, where there was inhibition of neutrophil migration to the intra-peritoneal cavity of treated animals, demonstrating the anti-inflammatory activity of 6CN10. In the acute toxicological study after treatment with the dosage of 1000 mg/kg 6CN10, it was observed a reduction in the food intake and in the body weight in females. The examined hematological parameters remained unaffected. The treatment was able to raise levels of ALT and AST, in both sexes, corroborating with histopathological findings that showed evidence of Hepatotoxicity. The kidneys, heart and lungs showed no histological particularities. Therefore, the results presented in this study showed a promising effect of 6CN10 as an analgesic and anti-inflammatory substance, however its security should be better investigated. / Os compostos heterocíclicos são as maiores fontes de fármacos sintéticos e têm crescido exponencialmente apresentando importantes aplicações na indústria farmacêutica. Entre os compostos heterocíclicos destacamos a classes dos tiofenos e seus derivados, que despertam grande interesse por apresentarem ações farmacológicas importantes, sobretudo, analgésica e antiinflamatória. O presente estudo se propôs a investigar a atividade antinociceptiva, antiinflamatória e a toxicidade pré-clínica aguda do derivado tiofênico 6CN10. A triagem farmacológica comportamental dos animais tratados (250, 500 e 1000 mg/kg) demonstrou alterações, tais como, analgesia e redução da ambulação. Não houve morte dos animais, nem presença de sinais tóxicos. A partir da triagem farmacológica determinou-se a utilização de três doses (25, 50 e 100 mg/kg) para os demais estudos. Nos testes de rota rod e campo aberto, não foram observadas alterações na coordenação motora dos animais, descartando a possibilidade de um efeito miorelaxante. Por meio de modelos indutores de nocicepção, como os testes das contorções abdominais induzidas por ácido acético, da formalina e da placa quente, foi observado uma atividade antinociceptiva dose-dependente de 6CN10. Tal efeito não demonstrou associar-se à via opióide de analgesia central, uma vez que este derivado não produziu efeito significativo no teste da placa quente, e por não ter sido bloqueado pela naloxona, um antagonista opióide padrão. 6CN10 inibiu significativamente o tempo de lambedura da pata em ambas as fases do teste formalina, sobretudo na fase inflamatória, se fazendo necessário uma análise da atividade antiinflamatória do derivado. Para este fim, utilizou-se o modelo de peritonite induzida pela carragenina, onde houve inibição da migração de neutrófilos para a cavidade intraperitoneal dos animais tratados, demonstrando a atividade antiinflamatória do 6CN10. No estudo toxicológico agudo após tratamento com a dose de 1000 mg/kg de 6CN10, foi observado redução da ingestão de alimentos e peso corpóreo nas fêmeas tratadas. Os parâmetros hematológicos analisados permaneceram inalterados. O tratamento foi capaz de elevar os níveis de ALT e AST, em ambos os sexos, corroborando com os achados histopatológicos que mostraram indícios de hepatotoxicidade. Os rins, coração e pulmões não apresentaram particularidades histológicas. Portanto, os resultados apresentados neste estudo evidenciaram um efeito promissor de 6CN10 como substância analgésica e antiinflamatória, contudo a sua segurança deve ser melhor investigada.

In the recent years area organic photovoltaics is generating a lot of interests because whole process of synthesis and fabrication is less energy intensive process as well as it is cost effective compared to conventional inorganic Si based photovoltaic technology. This work mainly deals with the fabrication and optimization of device fabrication conditions for organic photovoltaic materials. In first part of the work, the solar cell fabrication conditions were optimized for the commonly used system P3HT – PCBM. The fabricated device was optimized for the solvents used for the active material, concentration of the active material solution, donor- acceptor ratio of the active material, annealing conditions of the active layer and the metal evaporation conditions for the cathode. All the optimization procedures were carried out in controlled atmosphere to minimize the environmental effect inference during fabrication of the solar cell devices. All the characterization was carried out at ambient conditions. The efficiency of the solar cell was improved from 0.009% to 6.2%. the environmental stability of the fabricated devices were carried out after encapsulating it with epoxy based resin in both ambient conditions as well as extreme conditions like 85% RH at 25°C inside the humidity chamber. It was observed that both the data matches well with each other indicating proper encapsulation required to safe guard the device for the better performance over the period of time. Second part of this work mainly deals with understanding the structure property relationship of thiophene based donor- acceptor- donor molecule 2,5-dithienyl-3,4-(1,8-naphthylene) cyclopentadienone (DTCPA), which is highly crystalline, low band gap organic molecule which absorbs over entire visible region of the solar spectra. DTCPA crystals of various morphologies were prepared by various recrystallization routes. It was observed that macro scale morphology of these crystals differs from each other. Also depending on the method of recrystallization sizes of the crystals also varies. All the recrystallized DTCPA shows strong orientation toward (001) direction. However, it was observed that lattice parameters of these crystals slightly differ from each other owing to the recrystallization methodology. These variations in crystal parameters are more than 0.02 which is significant. It was also observed that the crystallite sizes depend on the recrystallization routes. Slow evaporation of concentrated solution (SEC) grown crystals has the larger crystallite size of 170nm. It was observed that absorption range of these crystals slightly differ from each other owing to the change in the crystallite sizes and crystal parameters. Third part of this work deals with the fabrication and optimization of thermal evaporation process of DTCPA for photovoltaic applications. DTCPA is stable at higher temperatures as well as has sharp melting point which make it ideal candidate for thermal evaporation. In this work films of DTCPA were fabricated for various evaporation rates by thermal evaporation technique. Chemical integrity of the molecules upon evaporation is found to be intact as observed from FTIR spectroscopy. XRD shows that at lower (25 W/m2) as well as higher (40 W/m2) films are oriented to (001), (400) as well as (311) directions, at 30 W/m2 and 35 W/m2 there is a strong orientation towards (311) and (001) directions respectively. Photo luminescence studies indicate that there is strong 410 nm emission for films deposited at the power of 25 W/m2 and 40 W/m2. Microscopic studies confirm that morphology is dependent on the deposition rates as it changes with the change in deposition rate. This in turn reflects in the device characteristics of these films. It was observed that films deposited at high deposition rates show better device characteristics with high VOC and current density values. All these device fabrication and characterizations were carried out in ambient conditions. Fourth part of this work deals with P3HT - DTCPA composites which exhibit wide range of light absorption. It was observed that DTCPA act as nucleating centers for the P3HT molecules and increases crystallinity in the composite. Furthermore, DTCPA helps in exciton separation because of donor and acceptor moieties present in the molecule. It also helps in charge transportation because of its crystalline nature and further it induces molecular ordering in the P3HT matrix. The band diagram of P3HT- DTCPA suggests that the band edges of both materials are ideal for charge separation. In addition, crystalline nature of the DTCPA molecule helps in effective charge transportation. J-V characteristics shows that there is large built in potential in the devices from these blends leading to large Voc. Composites with lower DTCPA loadings show higher efficiency than with higher loadings. These devices were prepared in ambient conditions and needs to be optimized for obtaining better device properties. In the fifth part of the work two types of system were studied to understand the band edge matching on the photovoltaic properties, carbazole based copolymers and DTCPA based copolymers. In the case of carbazole based copolymers it was observed that by copolymerizing carbazole with thiophene based derivatives lowers the band gap and modifies the HOMO and LUMO levels for better suit for the photovoltaic device fabrication. It was observed that that is two orders of improvements in the efficiency by co polymerizing carbazole with benzothiodizole as improves the JSC and VOC. Also the copolymerization of carbazole with both benzothiodiazole and bithiophene results in better light harvesting as the optical band gap was lowered. In the case of DTCPA copolymers with DTBT and DHTBT as both are random copolymers the solubility was low as well as their HOMO band edge was mismatched with the PEDOT: PSS which is a hole transport layer. However, the alternate polymerization of DTCPA with DTBT improved the band edge matching and also the solubility. As a result there was tenfold improvement in the charge collection and hence the efficiency was improved from 0.02% to 2.4%. Many of the conducting polymers have good material property but poor filmability. In the sixth part of this work deals with fabrication of device quality films by alternate deposition technique like pulsed laser deposition. Two types of system were studied in this work (i) polypyrrole- MWCNT nanocomposites and (ii) Poly DTCPA polymer. In both the cases it was observed that chemical integrity of the polymer retained during ablation. PolyDTCPA films were fabricated by pulsed laser deposition by both IR (Nd-YAG) and UV (KrF) laser source. Morphological studies indicate that IR laser ablated films were particulate in nature whereas UV laser ablated films were grown as continuous layers as polyDTCPA absorbs better in UV region. As a result the IV characteristics indicate that IR laser ablated films are resistive in nature and UV laser ablated films are good rectifiers indicating the suitability of the process for fabrication of device quality films.