Detection of Albumin Using Gold Nanoparticles-mediated Microfluidic Paper-based Analytical Devices Shova A. Hardiyanti,1) Noval D. Wijaya,1) Lusi Krisdiyanti,1) Salsabillah F. A. Putri,1) Hermin Sulistyarti,1) Ani Mulyasuryani,1) Setyawan P. Sakti,2) Aulanni^am,1) Akhmad Sabarudin,1, a)
1)Department of Chemistry, Faculty of Science, Brawijaya University, Malang 65145, Indonesia.
2)Department of Physics, Faculty of Science, Brawijaya University, Malang 65145, Indonesia.
Abstract
In this work, we develop the rapid diagnostic kit potentially applied as point-of-care testing for kidney disease (nephropathy) through the detection of albumin in urine samples. For this purpose, gold-nanoparticle (AuNPs) in combination with anionic dyes of Bromocresol Purple (BCP) and Bromothymol Blue (BTB), which are immobilized onto distance-based microfluidic paper-based analytical devices (d-uPADs), are utilized as sensing reagents. In this device, two mechanisms operate for quantitative and semiquantitative detection of albumin using d-uPAD, which includes (1) protein error of pH indicator by direct reaction of albumin with dyes, and (2) full corona protein formation of AuNPs with albumin. These synergistic reaction mechanisms facilitate the sharp color change of dyes, which are easily detected by the naked eye. Some parameters affecting the sensitivity of the proposed method, such as dyes concentration, pH, reagent volume ratio, reagent immobilization, and reaction time are investigated in detail. Inexpensive, disposable, and easy-to-use without technical expertise for albumin detection are advantages of the proposed method. Additionally, the proposed method has high precision (RSD: 1.08-1.37%) and accuracy (95.74-99.96%).
