Modification of Microfluidic Paper-Based Devices with Silica Nanoparticles

ELIZABETH EVANS; ELLEN FLAVIA MOREIRA GABRIEL; TOMAS E. BENAVIDEZ; WENDELL KARLOS TOMAZELLI COLTRO; CARLOS D. GARCIA

ROYAL SOC CHEMISTRY

Lugar: CAMBRIDGE; Año: 2014 p. 5560 - 5560

his paper describes a silica nanoparticle-modified microfluidic paper-based analytical device (mPAD) with improved color intensity and uniformity for three different enzymatic reactions with clinical relevance (lactate, glucose, and glutamate). The mPADs were produced on a Whatman grade 1 filter paper and using a CO2 laser engraver. Silica nanoparticles modified with 3-aminopropyltriethoxysilane were then added to the paper devices to facilitate the adsorption of selected enzymes and prevent the washing away effect that creates color gradients in the colorimetric measurements. According to the results herein described, the addition of silica nanoparticles yielded significant improvements in color intensity and uniformity. The resulting mPADs allowed for the detection of the three analytes in clinically relevant concentration ranges with limits of detection (LODs) of 0.63 mM, 0.50 mM, and 0.25 mM for lactate, glucose, and glutamate, respectively. An example of an analytical ap