On-chip immunoassay for determination of urinary albumin.
An immunoassay performed on a portable microfluidic device was evaluated for the determination of urinary albumin. An increase in absorbance at 500 nm resulting from immunoagglutination was monitored directly on the poly(dimethylsiloxane) (PDMS) microchip using a portable miniature fibre-optic spectrometer. A calibration curve was linear up to 10 mg L(-1) (r(2) = 0.993), with a detection limit of 0.81 mg L(-1) (S/N = 3). The proposed system showed good precision, with relative standard deviations (RSDs) of 5.1%, when evaluated with 10 mg L(-1) albumin (n = 10). Determination of urinary albumin with the proposed system gave results highly similar to those determined by the conventional spectrophotometric method using immunoturbidimetric detection (r(2) = 0.995; n = 15).
Centre for Excellence in Omics-Nano Medical Technology Project Development, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, 10330, Thailand.
Wanida
W
Laiwattanapaisal
Temsiri
T
Songjaroen
Thitima
T
Maturos
Tanom
T
Lomas
Assawapong
A
Sappat
Adisorn
A
Tuantranont