Recent advances in the area of nanotechnology have led to interesting applications of nanomaterials in medicine, especially in the areas of imaging and treatment. This thesis presents the development of two molecularly imprinted polymers (MIPs) based on the same fluorescent functional monomer. One MIP, prepared in the bulk format, is investigated for its ability to detect tamoxifen and its metabolites. The other MIP synthesised in the nanogel format, holds the potential to be used as pH-responsive drug delivery system. Four objectives were identified within this project. The first was the design and synthesis of fluorescent functional monomer. Two coumarin derivatives carrying a polymerisable unit, for covalent bonding within the polymer, and a carboxylic moiety, for interaction site with the template, were synthesised and characterised. However, only one of them (the VCC: 6-vynilcoumarin-4-carboxylic acid) showed high fluorescent yield and was selected as functional monomer. The second objective involved the development of a detection system based on bulk MIP containing the VCC fluorescent monomer. This system proved effective in generating a detectable signal upon binding the analytes. The signal was observed as a quenching of the polymer fluorescence and it was proportional to the amount of target molecules detected. The third objective was the preparation of tamoxifen-imprinted nanogels for potential application in the drug delivery field. The optimisation of the procedure gave a set of NIP/MIP with the desired solubility, particle size and fluorescence emission. These nanogels were then employed in the last objective, which involved the toxicity study and evaluation of the drug loading on of transgenic line of zebrafish. The nanogels were non-toxic at the tested concentrations and the presence of tamoxifen was confirmed.

<p>In the present work, molecular dynamics simulations were used to evaluate the molecular interactions in prepolymerization mixtures, as occurring during production of molecularly imprinted polymers. The systems simulated were produced based on earlier studies for reference of results. Four systems were simulated in order to investigate the effect on molecular interactions based upon the choice of porogen (acetonitrile or chloroform) and proton transfers. The systems consisted of phenylalanine anilide as template, methacrylic acid as functional monomer, ethylene glycol dimethacrylate as crosslinker and 2,2’-azobis-(2-methylpropionitrile) as radical initiator, with either acetonitrile or chloroform as porogen. Trajectories from the simulations were evaluated through radial distribution function analysis, grid density analysis and hydrogen bond analysis to investigate molecular interactions and complex formations in the simulated complete prepolymerization mixtures. Focus was on functional monomer-template, crosslinker-template and template-template complex formations. The results showed that the porogen influences molecular interactions in complete prepolymerization mixtures. Formation of higher order complexes was confirmed in all of the systems involving all of the investigated molecular species in the prepolymerization mixtures. The results could also confirm the presence of previously observed complexes between functional monomer and template (2:1 and 1:1 stoichiometry) and the prevalence of template dimerization, as well as a high involvement of crosslinker in complex formation.</p>

As sulfonamidas são antibióticos amplamente utilizados na medicina humana e animal. Por apresentarem um custo relativamente baixo, além de seu uso medicinal são comumente utilizadas como aditivos nos alimentos para promover o crescimento de animais. O alto consumo das sulfonamidas é preocupante, pois grandes quantidades desses compostos são descartadas no ambiente por meio de excreções humanas, excreções animais e por águas residuárias industriais e hospitalares. A presença de sulfonamidas no ambiente, mesmo em níveis de traços, pode gerar uma toxicidade direta nas espécies expostas bem como a proliferação seletiva de bactérias resistentes, que podem transferir os genes de resistência para outras espécies bacterianas. O impacto ambiental negativo ocasionado por esse tipo de composto exige o monitoramento adequado e o consequentemente desenvolvimento de técnicas e métodos de análise e de preparo de amostra que consigam atingir suficientes intervalos e limites de detecção. Na atualidade a SPE é uma técnica bastante utilizada para extração de analitos em amostras ambientais, pois permite trabalhar com um consumo de solvente reduzido, sua reprodutibilidade é alta, o tempo de preparo de amostra é curto e permite a automatização. No formato automatizado on-line a fase extratora é empacotada em uma pré-coluna e ligada ao sistema cromatográfico geralmente por meio de uma válvula de seis pórticos. Dentre as possíveis fases para a SPE os polímeros molecularmente impressos (MIP) têm tornado-se atrativos por causa de sua alta seletividade em comparação com as fases extratoras tradicionais; além disso, permitem, mediante procedimentos simples, associar a tecnologia MIP com a tecnologia de materiais de acesso restrito - RAM (do inglês: restricted access media) obtendo assim os materiais RAM-MIP. Nesse trabalho foi sintetizado e avaliado o desempenho de um polímero de impressão molecular (MIP), e três polímeros de impressão molecular restritos à ligação de macromoléculas (RAM-MIP, BSA-MIP e RAM-MIP-BSA) para a pré-concentração seletiva de sete sulfonamidas (SNs) em amostras complexas para análise em sistema HPLC-bidimensional. Os materiais obtidos foram avaliados em termos de fator de retenção, seletividade, seletividade competitiva e capacidade de eliminação de macromoléculas. O polímero BSA-MIP apresentou os melhores resultados, demonstrando-se muito mais seletivo para sulfonamidas do que para alguns interferentes como fluoroquinolonas, cafeína, ácido acetilsalicílico entre outros, também demonstrou uma capacidade de exclusão de macromoléculas de 97,63% ao ser testado com uma solução de 44 mg mL-1 de BSA. / Sulfonamides are antibiotics widely used in human and veterinary medicine. Due to their relatively low cost and their therapeutic effects, they are frequently employed as growth promoting additive in animal food. This high consumption causes that high amounts of them are being ejected to the environment through the animal and human excrements or industrial and hospital wastewater. Even in trace amount, these compounds can produce direct toxicity in several species and the selective spread of the antibiotic resistant bacteria that can transfer the resistance genes to others bacteria species. This negative impact has to be adequately monitored and, thus, there is a claim to the development of analytical and sample preparation techniques and methods that permit reaching to very low detection limits and intervals. Currently solid phase extraction (SPE) is the technique commonly used for isolation of analytes from environmental samples, since it allows working with smaller volumes of solvent, shorter sample preparation times, achieving high reproducibility and allowing automation. In automated on-line SPE the extracted phase is packed into a precolumn and linked to the chromatographic system, generally by a 6-port valve. Among the possible phases for SPE the molecular imprinted polymer (MIP) has become interesting because it is more selective than traditional extraction; moreover, through simple procedure it can be associated with the restricted acess media (RAM) producing the RAM-MIP and the MIP-BSA materials. Here we synthesized and evaluated the performance of one MIP and three molecular imprinted polymers linked to macromolecules (RAM-MIP, BSA-MIP e RAM-MIP-BSA) for a selective preconcentration of seven sulfonamides in complex samples for two-dimensional HPLC analysis. The synthesized materials was evaluated regarding the retention factor, competitive selectivity and elimination capacity of macromolecules. The BSA-MIP option showed the best results, achieving high selectivity for sulfonamides against others interferences such as fluoroquinolone, caffeine and acetylsalicylic acid; additionally presenting an exclusion capacity of 97,63% of macromolecules when was tested with a BSA solution at 44 mg ml-1.

As sulfonamidas são antibióticos amplamente utilizados na medicina humana e animal. Por apresentarem um custo relativamente baixo, além de seu uso medicinal são comumente utilizadas como aditivos nos alimentos para promover o crescimento de animais. O alto consumo das sulfonamidas é preocupante, pois grandes quantidades desses compostos são descartadas no ambiente por meio de excreções humanas, excreções animais e por águas residuárias industriais e hospitalares. A presença de sulfonamidas no ambiente, mesmo em níveis de traços, pode gerar uma toxicidade direta nas espécies expostas bem como a proliferação seletiva de bactérias resistentes, que podem transferir os genes de resistência para outras espécies bacterianas. O impacto ambiental negativo ocasionado por esse tipo de composto exige o monitoramento adequado e o consequentemente desenvolvimento de técnicas e métodos de análise e de preparo de amostra que consigam atingir suficientes intervalos e limites de detecção. Na atualidade a SPE é uma técnica bastante utilizada para extração de analitos em amostras ambientais, pois permite trabalhar com um consumo de solvente reduzido, sua reprodutibilidade é alta, o tempo de preparo de amostra é curto e permite a automatização. No formato automatizado on-line a fase extratora é empacotada em uma pré-coluna e ligada ao sistema cromatográfico geralmente por meio de uma válvula de seis pórticos. Dentre as possíveis fases para a SPE os polímeros molecularmente impressos (MIP) têm tornado-se atrativos por causa de sua alta seletividade em comparação com as fases extratoras tradicionais; além disso, permitem, mediante procedimentos simples, associar a tecnologia MIP com a tecnologia de materiais de acesso restrito - RAM (do inglês: restricted access media) obtendo assim os materiais RAM-MIP. Nesse trabalho foi sintetizado e avaliado o desempenho de um polímero de impressão molecular (MIP), e três polímeros de impressão molecular restritos à ligação de macromoléculas (RAM-MIP, BSA-MIP e RAM-MIP-BSA) para a pré-concentração seletiva de sete sulfonamidas (SNs) em amostras complexas para análise em sistema HPLC-bidimensional. Os materiais obtidos foram avaliados em termos de fator de retenção, seletividade, seletividade competitiva e capacidade de eliminação de macromoléculas. O polímero BSA-MIP apresentou os melhores resultados, demonstrando-se muito mais seletivo para sulfonamidas do que para alguns interferentes como fluoroquinolonas, cafeína, ácido acetilsalicílico entre outros, também demonstrou uma capacidade de exclusão de macromoléculas de 97,63% ao ser testado com uma solução de 44 mg mL-1 de BSA. / Sulfonamides are antibiotics widely used in human and veterinary medicine. Due to their relatively low cost and their therapeutic effects, they are frequently employed as growth promoting additive in animal food. This high consumption causes that high amounts of them are being ejected to the environment through the animal and human excrements or industrial and hospital wastewater. Even in trace amount, these compounds can produce direct toxicity in several species and the selective spread of the antibiotic resistant bacteria that can transfer the resistance genes to others bacteria species. This negative impact has to be adequately monitored and, thus, there is a claim to the development of analytical and sample preparation techniques and methods that permit reaching to very low detection limits and intervals. Currently solid phase extraction (SPE) is the technique commonly used for isolation of analytes from environmental samples, since it allows working with smaller volumes of solvent, shorter sample preparation times, achieving high reproducibility and allowing automation. In automated on-line SPE the extracted phase is packed into a precolumn and linked to the chromatographic system, generally by a 6-port valve. Among the possible phases for SPE the molecular imprinted polymer (MIP) has become interesting because it is more selective than traditional extraction; moreover, through simple procedure it can be associated with the restricted acess media (RAM) producing the RAM-MIP and the MIP-BSA materials. Here we synthesized and evaluated the performance of one MIP and three molecular imprinted polymers linked to macromolecules (RAM-MIP, BSA-MIP e RAM-MIP-BSA) for a selective preconcentration of seven sulfonamides in complex samples for two-dimensional HPLC analysis. The synthesized materials was evaluated regarding the retention factor, competitive selectivity and elimination capacity of macromolecules. The BSA-MIP option showed the best results, achieving high selectivity for sulfonamides against others interferences such as fluoroquinolone, caffeine and acetylsalicylic acid; additionally presenting an exclusion capacity of 97,63% of macromolecules when was tested with a BSA solution at 44 mg ml-1.

Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-09-19T17:06:54Z No. of bitstreams: 1 JosimarAraujo.pdf: 950712 bytes, checksum: 6ec752a1c9c3751ffeba0d040eb09762 (MD5) / Made available in DSpace on 2017-09-19T17:06:54Z (GMT). No. of bitstreams: 1 JosimarAraujo.pdf: 950712 bytes, checksum: 6ec752a1c9c3751ffeba0d040eb09762 (MD5) Previous issue date: 2017-09-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The present work describes a study of the construction of an electrochemical sensor involving sol-gel process and molecular imprinting for detection of triclosan. The sol-gel process is a process in which a network is formed from a solution, by progressively changing a liquid precursor, from a sol to a gel and, in most cases, finally to a dry network. In turn, molecular imprinting is a method of induced formation of some predetermined selectivity recognition element for some template molecule. Thus, for the determination of the template molecule triclosan, 5-chloro-2-(2,4-dichlorophenoxy)-phenol, the following steps were performed: 1) verification of a glassy carbon electrode modified with chitosan and multi-walled carbon nanotubes, and molecularly imprinted siloxanes, would be suitable for the voltammetric detection of triclosan; 2) to observe if a network would be formed with the sol-gel process and to evaluate the mechanical stability of the electrochemical sensor constructed; 3) to evaluate the modified electrode as an electrochemical sensor with selectivity, specificity and detection limit for the determination of triclosan in aqueous solutions; 4) to verify the applicability of the proposed sensor by detecting of triclosan oxidation in real samples. The results showed that glassy carbon electrode modified with chitosan, multi-walled carbon nanotubes and molecularly imprinted siloxanes, constructed by sol-gel and molecular imprinting processes, presented mechanical stability, sensitivity, selectivity, specificity and applicability as an electrochemical sensor for the detection of triclosan in commercial samples of physical moisturizer and of toothpaste. / O presente trabalho descreve um estudo da construção de um sensor eletroquímico envolvendo processo sol-gel e impressão molecular para detecção de triclosan. O processo sol-gel é um procedimento no qual uma rede é formada a partir de uma solução. Esta formação é por meio de uma mudança progressiva deste líquido inicial, de um sol para um gel e, na maioria dos casos, finalmente para uma rede seca. Por sua vez, a impressão molecular é um método de formação induzida de elementos de reconhecimento com seletividade predeterminada para alguma molécula molde. Assim, para a determinação da molécula molde triclosan, 5-cloro-2- (2,4-diclorofenoxi)-fenol, as seguintes etapas foram executadas: 1) verificar se um eletrodo de carbono vítreo modificado com quitosana, nanotubos de carbono de paredes múltiplas e siloxanos molecularmente impressos seria adequado para a detecção voltamétrica do triclosan; 2) averiguar a formação de uma rede com o processo sol-gel e avaliar a estabilidade mecânica do sensor eletroquímico construído; 3) avaliar a sensibilidade do eletrodo modificado como um sensor eletroquímico com seletividade, especificidade e limite de detecção para a determinação de triclosan em soluções aquosas; e 4) comprovar a aplicabilidade do sensor proposto mediante a detecção de sinal de oxidação de triclosan em amostras reais. Os resultados mostraram que eletrodos de carbono vítreo modificados com quitosana, nanotubos de carbono de paredes múltiplas e siloxanos molecularmente impressos, construídos por processo sol-gel e impressão molecular, apresentaram estabilidade mecânica, sensibilidade, seletividade, especificidade e aplicabilidade como um sensor eletroquímico para a detecção de triclosan em amostras comerciais de hidratante corporal e de creme dental.

As Sulfonamidas (SAs) são antibióticos de uso muito comum na medicina veterinária, sendo também aplicadas na medicina humana. Os resíduos dessas substâncias, ou dos seus metabolitos na carne e outros alimentos, podem causar efeitos adversos para a saúde dos consumidores como, por exemplo, resistências a antibióticos e alergias. Este trabalho apresenta o desenvolvimento e aplicação de métodos modernos de preparo de amostra para determinação de multiresíduo de sulfonamidas em alimentos por cromatografia líquida acoplada a espectrometria de massas e ultravioleta visível. Dentre os métodos de preparo de amostra, aplicou-se o método de extração QuEChERS (Quicky, Easy, Cheap. Effective, Rugged, Safe) modificado, em combinação com a cromatografia liquida acoplada a espectrometria de massas, para a análise de dez sulfonamidas em amostras de músculo de frango e bovino. No segundo estudo, seguindo a tendência de miniaturização, sintetizou-se um polímero molecularmente impresso (Sulfadimetoxina-MIP) para uso como sorbente em dispositivos de Microextração com Sorbentes Empacotado (MEPS). O método, denominado SDM-MIP-MEPS, foi otimizado e aplicado em amostras de músculo de frango usando a cromatografia liquida com detecção por ultravioleta-visivel. Embora o uso do polímero molecularmente impresso (MIP) como sorbente seletivo para o MEPS já tenha sido reportada em dois trabalhos, pela primeira vez é descrito a aplicação de um MIP impresso com sulfdimetoxina (SDM), usando MEPS para extração de sulfonamidas em músculo de frango. Portanto, a novidade neste caso, é o uso da nova técnica extração miniaturizada (MEPS) com o polímero sintetizado sulfadimetoxina-MIP como sorbente de empacotamento. As metodologias foram validadas com sucesso de acordo com as diretrizes 657/2002/EU. / Sulfonamides are widely used in veterinary and human medicine. Residues of these compounds, or their metabolites in animal meats and other foods, are toxic and can cause side effects in human\'s health, such as resistance to antibiotics and allergic reactions. This study describes the development and application of a modern sample preparation approach for sulfonamides multiresidue determination in food by chromatographic methods coupled to mass spectrometry and ultraviolet-visible spectroscopy. Among those sample preparation methods, the modified QuEChERS extraction in combination with liquid chromatography in tandem with mass spectrometric detection was applied to the analysis of residues of 10 sulfonamides in chiken and cattle muscle. In the second study, following the miniaturization trends, it was synthesized a molecularly imprinted polymer (Sulfadimethoxine-MIP), for application as sorbent in Microextraction by Packed Sorbents (MEPS). The extraction method was optimized and successfully applied to chicken muscle samples in combination with highperformance liquid chromatography by ultraviolet-visible detection. Although the use of MIPs as selective packing materials for MEPS has already been reported in two papers, is first time that application of a MIP imprinted with Sulfadimethoxine is evaluated for the extraction of sulfonamides in chicken muscle. Therefore the novelty of the present work is the use of this new miniaturization extraction technique with synthesized sulfadimethoxine-MIP polymer as packing sorbent. The methods were successfully validated according to the 2002/657/EC guidelines.

Molecularly imprinted polymers (MIPs) have been compared to natural antibodies in that they can specifically bind target compounds in a similar way that antibodies specifically bind to an antigen. The attraction of the MIPs technology is the ease of creating binding elements which are relatively cheap compared with the process of isolating natural antibodies. In this research monoterpenes, such as α-terpineol, were chosen to be the model compounds for investigating the molecular imprinting of small, poorly functionalised organic compounds. The conventional non-covalent approach was mainly used to synthesise these MIPs, but the sacrificial-spacer semi-covalent approach was also investigated. A less widely used method, porogen-imprinting - a variant of non-covalent imprinting - was adapted for α-terpineol. The latter novel terpene MIP appeared to specifically bind α-terpineol, by hydrogen bonding, so the polymer was characterised in detail. The main parameters which were altered for preparing non-covalent MIPs included the template (α-terpineol, (-)-menthol or trans-terpin); the functional monomer (methacrylic acid, 2-hydroxyethyl methacrylate, bilirubin and phenol [for the semi-covalent MIP]); the cross-linking monomer (ethylene glycol dimethacrylate, divinylbenzene and trimethylolpropane trimethacrylate); and also the polymerisation method (block or precipitation polymerisation). The binding specificity and cross-reactivity for all the polymers were tested using a liquid batch-binding setup. The batch-binding setup required the detection of analyte that was not bound in order to calculate by difference the fraction of analyte bound to the polymer. Initially the terpenes were to be detected by a colorimetric method; however attempts to make the method sensitive and reliable were not successful. In comparison, gas chromatography was more reliable for the detection of terpenes and was used for the experiments presented in this thesis. 1H-NMR studies of the interaction between α-terpineol and acetic acid (as a non-polymerisable analogue of methacrylic acid) were investigated as a basis for understanding the binding to the carboxyl functional group moiety employed in many of the non-covalent MIPs that were made. The interaction between (-)-menthol and phenol was also investigated because the phenol moiety was employed in the semi-covalent MIP. Only selected MIPs, which appeared to specifically bind the template, were physically characterised. This included optimising the batch-binding parameters, scanning electron microscopy imaging, surface area and pore radius analysis and in some cases Fourier transform-infrared spectroscopy of the polymers.

The aim of this study was to develop methods for sample preparation for 8-OHdG in blood plasma samples with different solid phase extraction techniques using HPLC with an elec- trochemical detector. The solid phase extraction cartridges used were Chromabond® C18, Oasis® MAX, and three types of SupelMIPTM cartridges for chloramphenicol, riboflavin, and nitroimidazoles. The SupelMIPTM cartridges are based on molecularly imprinted polymers- technique. The separation of 8-OHdG in samples extracted from blood plasma was carried out with a Thermo Quest Hypersil Division ODS column (250 mm × 4 mm, 3μm I.D.) and methanol:buffer (10:90, v/v) as mobile phase. Recovery and selectivity was studied for the different solid phase extraction methods. The highest recovery was obtained using the Chromabond C18 cartridge with a recovery of 92%, and CV coefficient 9.5% (n = 4). 8-OHdG could not be extracted on MIP-cartridges for chloramphenicol or riboflavin, but was retained on MIP columns for nitroimidazoles, and the highest recovery was 49%.

Molecularly imprinted polymers (MIPs) are biomimetic sensing elements that combine the accuracy and highly specific binding affinity of a biosensor, with the robustness and reusability associated with artificial electrochemical sensors. This thesis investigates the application of a MIP sensor to address the challenge of phosphate detection in precision agriculture. Traditional chemical sensing approaches using portable electrochemical sensors display a significant cross-interference between inorganic phosphate and other nutrient ions. This is due to the low position of phosphate in the Hofmeister Selectivity Series for anions, its high electronegativity and its pH dependent structure, resulting in a molecule that is very difficult to detect. To address this challenge, a sensor was created by spin coating a phosphate selective MIP onto a substrate containing a series of electrodes. These electrode devices allowed for electrical measurements to be taken using an inductance, capacitance and resistance (LCR) testing station, and to observe the change in the materials dielectric constant as the binding sites become occupied by the target analyte. The devices underwent several design reiterations to produce an optimised setup consisting of 100 interdigitated chrome electrodes with a width of 1 μm and a separation distance of 1 μm on a quartz substrate. The final electrode design was used to carry out a nutrient cross-interference study across several polymer permutations. The purpose of this was to develop an optimised MIP formulation for binding specifically to inorganic phosphate ions. From this study, an optimal phosphate selective MIP was identified, based upon a binding site constructed from methacrylic acid around a diphenyl phosphate template molecule. During capacitance measurements, this MIP formulation demonstrated a clear preferential response to phosphate (1610 pF) over the average capacitance results observed following exposure to the competing nitrate (1286 pF) and sulphate (1212 pF) nutrients tested in the cross-interference study.

Orientador: Douglas Soares Galvão / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-20T20:43:55Z (GMT). No. of bitstreams: 1 Moura_FranciscoAlirioAlmeidaGomesde_M.pdf: 1452512 bytes, checksum: 5bfe0662fc16432eada98d772559aa36 (MD5) Previous issue date: 2012 / Resumo: Nesse estudo, investigamos, utilizando ferramentas computacionais, o problema do desenvolvimento racional de polímeros molecularmente impressos (MIP). Utilizamos vários tipos de simulações moleculares: dinâmica molecular, simulated annealing e método de Monte Carlo para alcançar uma seleção de monômeros funcionais baseada em uma biblioteca de monômeros candidatos para uma dada substância-alvo de interesse. Aplicamos esses métodos à simulação das soluções pré-polimerização para a construção de um MIP para a substância 17ß-estradiol, que é uma molécula orgânica de interesse médico e ambiental. Fomos bem sucedidos em simular a solução pré-polimerização para nove monômeros diferentes e construímos uma lista ordenada de possíveis melhores candidatos dentre esses nove / Abstract: In the present study, we investigated by means of computational tools, the problem of rational design of Molecularly Impressed Polymers (MIP). We used several different types of simulations: molecular dynamics, simulated annealing and Monte Carlo method to achieve a selection of functional monomers based on a library of candidates for the functional monomers for some given target substance of interest. We applied these methods to pre-polimerization solutions for the design of a MIP for the substance 17ß-estradiol, which is an organic molecule of medical and environmental interest. We were successful in simulating the pre-polimerization solutions for nine different monomers and building an ordered list of possible best monomers among these candidates / Mestrado / Física / Mestre em Física