Evaluation and application of a paper-based device for the determination of reactive phosphate in soil solution

Abstract

The evaluation and validation of a new low-cost microfluidic paper-based analytical device (μPAD) for the determination of reactive phosphate in soil solution is described. This device allows up to 15 replicate measurements of reactive phosphate on one credit card-sized device and requires only a desktop or hand scanner for signal detection and quantification. The proposed method showed a linear response between 0.1 and 1.0 mg L-1 and between 1.0 and 10.0 mg L-1 P with a limit of detection of 0.05 mg L-1 P. When applied to the analysis of soil solution, there was excellent agreement between results obtained using the μPAD and those obtained by a reference spectrophotometric method, as indica..