Polímeros Molecularmente Impressos (MIPs) são polímeros sintéticos que apresentam alta seletividade a uma molécula de interesse. O objetivo deste trabalho foi a síntese e caracterização de MIPs para aplicação na extração em fase sólida (SPE), visando a determinação de fenilalanina. Os MIPs foram sintetizados a partir do MAA, fenilalanina, EGDMA, AIBN, em clorofórmio. Também foi sintetizado o polímero não-impresso (NIP), para controle da seletividade dos MIPs. A dessorção da fenilalanina foi realizada em extrator Soxhlet. Os MIPs e NIP foram caracterizados pelas técnicas de análise: FTIR, UV-Vis, MEV, DSC e TG. O MIP apresentou maior capacidade adsortiva à fenilalanina do que o NIP, com uma taxa média de adsorção de 55% comparada a 11% para o NIP. Por MEV o MIP apresentou superfície mais porosa, importante característica para aplicação em SPE. Os estudos realizados mostraram que o MIP sintetizado apresentou grande potencial para aplicação em técnica de SPE.

Abstract Molecularly imprinted polymers (MIPs) are synthetic polymers that have high selectivity to a molecule of interest. The objective of this work was the synthesis and characterization of MIPs for use in solid phase extraction (SPE), in order to determine Phenylalanine. The MIPs were synthesized from the MAA, Phenylalanine, EGDMA AIBN, in chloroform. Non imprinted polymer (NIP) was synthesized to control the selectivity of MIPs. The desorption of Phenylalanine was carried out in Soxhlet extractor. The MIPs and NIP were characterized by the following analytical techniques: FTIR, UV-Vis, SEM, DSC and TG. MIP showed higher adsorption capacity to Phenylalanine than the NIP with an average rate of adsorption of 55% compared to 11% for NIP. SEM MIP showed more porous surface, an important feature for use in SPE. The synthesized MIP in the present study showed great potential for use in SPE technique.

Films of collagen (CLG) and poly(N-isopropylacrylamide), PNIPAAm, were prepared by casting from water solutions. These bioartificial polymeric materials were studied to examine the influence of PNIPAAm content and glutaraldehyde vapor cross-linking on the thermal and biological stability of CLG. Mixtures, ranging from 20-80 wt% CLG composition, were cross-linked through exposure to glutaraldehyde vapors. Thermal and morphological properties of the films, cross-linked or not, were investigated by differential scanning calorimetry, thermogravimetry, and scanning electron microscopy, with the aim of evaluating miscibility, thermal stability, and interactions among the constituents. The experimental results indicated that the homopolymers are not thermodynamically compatible. However, there is good evidence that effective interactions, probably due to hydrogen bond formation, takes place between the constituents. These interactions are more evident on the samples that were not cross-linked. DSC studies revealed that PNIPAAm exerts a thermal stabilizing effect on uncross-linked CLG, while the cross-linking with glutaraldehyde affects only the biological polymer, preventing the interactions with PNIPAAm. SEM micrographs of the uncross-linked mixtures showed that the morphology, in all compositions studied, remains similar to the pure collagen. In the corresponding cross-linked samples, a more compact aggregation is observed although no appreciably changes can be seen.