An array of highly selective Fabry-Perot optical-channels for biological fluids analysis by optical absorption using white light source for illumination

This paper describes a laboratorial microsystem (Microlab) used to measure the concentration of biomolecules in biological fluids. Rather than just one measurement channel, it comprises 16 optical-channels that enable the measurement of the concentration of 16 different biomolecules with the same device. An array of 16 optical filters based on Fabry-Perot thin-films optical resonators has been designed. Each optical-channel is sensitive in a single wavelength with a FWHM less than 6 nm and with a peak intensity higher than 86%. The 16 optical channels array fabrication requires only 4 masks, used with different deposition time. The Microlab can easily be tuned during fabrication to analyze different biomolecules only by adjusting the deposition times without affecting the device layout. A commercially available passband optical filter with a passband wavelength in 450-650 nm is used. The Microlab requires only a white light source for illumination due to the use of selective optical filters. The quantitative measurement of uric acid in urine is demonstrated. Such a device is extremely suitable for clinical diagnosis application in clinical laboratories and at a patient’s home because of its small size, low-cost and portability.Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BD/1281/2000. Fundo Europeu para o Desenvolvimento Regional - POCTI/33747/ESE/1999