Fig. 5

Specificity (a) and sensitivity (b) of LFSA for rongalite. a 80 μL of a rongalite solution (10 μg/mL) was added to the sample pad of the assembled strips. This step was repeated for the other counter targets including formalin for the specificity tests. Deionized water was used as a control. b Rongalite standard solutions with varying concentrations (0, 0.8, 1, 5, and 10 μg/mL) were prepared. 80 μL of the standard solutions was pipetted to the sample pad, and the observation of red color within 15 min on the test line was regarded as the criteria for determining the detection limit