Construction and evaluation of microsystems for flow analysis / Construção e avaliação de microssistemas para analise em fluxo

AUTOR(ES)
DATA DE PUBLICAÇÃO

2008

RESUMO

This work describes the construction, characterization and application of microsystems for flow analysis. Laser ablation was employed for the development of a system in poly(methylmethacrylate), whose channels, with rectangular cross sections measuring 200 mm width by 4,5 mm depth, were sealed with an adhesive plastic film. This device supported flow rates up to 2,0 mL min without leaking and its application for the photometric determination of Fe(II) in medicines provided results that did not differ significantly of those obtained by flame atomic absorption spectrometry at a confidence level of 95 %. The deep UV-photolithography was used for the construction of microsystems in urethane / acrylate based resin. The channels with triangular cross sections and dimensions between 200 e 600 mm were sealed with a layer of the same resin, forming a monolithic structure that supported flow rates up to 3.0 mL min. Plastic optical fibers and hypodermic needles were coupled to the devices and used for the integration of the optical detection systems and for the access of the working solutions, respectively. A microsystem with an integrated flow cell for fluorimetric detection and two confluence points was applied to the determination of Ca e Mg in mineral waters. Other two devices were separately applied to the photometric determination of Cr(VI) in contaminated waters and in metallic alloys, and to the determination of Cl in mineral waters. For all the applications, the concentrations obtained agreed with those determined by batch methods (spectrophotomety and complexometric titration). The generation of extremely small volumes of residues (ca. 25 mL of solution after an 8-h working day) indicates that the proposed devices appropriately accomplish the requirements established by the Green Chemistry

ASSUNTO(S)

fotolitografia flow analysis photolithography green chemistry quimica verde microfabrication analise em fluxo microfabricação

ACESSO AO ARTIGO

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