Desenvolvimento de dispositivos microfluídicos em poliéster-toner para diagnósticos clínicos com detecção colorimétrica

• Autor(a) principal: Souza, Fabrício Ribeiro de
• Data de Publicação: 2013
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/3165
• topic: Dispositivos em poliéster-toner; Diagnóstico clínico; Detecção colorimétrica; QUIMICA::FISICO-QUIMICA

This report describes the fabrication of a minimally instrumented polyestertoner device (PTD) to perform by the first time, clinical diagnostics with colorimetric detection and microfluidic transport by capillary action. A conventional digital camera, a cellphone camera, an optical microscope, and a scanner mode from a multifunction printer were evaluated for using as colorimetric detector. In order to study the analytical performance it was used a platform containing nine detection zones directly printed on a polyester film. It has been observed that all electronic devices studied could be applied as colorimetric detector. However, the scanner exhibited the best performance on the control of two problems often observed in the images acquisition, which are related to the ambient light and focus. Due to the best results, the analytical feasibility of the scanner was evaluated for the determination of Fe2+ in drugs samples by using the 1,10-phenanthroline method. The data were compared to results achieved by a reference spectrophotometric method. Based on a statistical analysis, it was not been found significance differences (P=0,05). Afterwards, the scanner was chosen to monitor the colorimetric response of clinical assays regarded to the detection of glucose, total protein, cholesterol, and triglycerides on a PTD. The proposed device exhibited good inter and intra-device reproducibility (relative standard deviation values lower than 6%). A semi-quantitative analysis of glucose, total protein, and cholesterol in an artificial serum sample provided results similar to the data provide by the supplier. The shelf life of PTDs was evaluated in a period of five days, using the glucose assay at three different temperature: 10 ºC, 25 ºC e 40 ºC. The shelf life was estimated to be c.a. three days, taking into account that in this period there was a lost of 50% in the mean color intensity. Lastly, it was observed that the addition of a disaccharide (trehalose) ensures the enzymatic stability at the different temperatures during five consecutive days. The cost of a PTD has been estimated to be ca. R$ 0.40 taking into account the fabrication process.