An Environmentally Friendly Compact Microfluidic Hydrodynamic Sequential Injection System Using Curcuma putii Maknoi & Jenjitt. Extract as a Natural Reagent for Colorimetric Determination of Total Iron in Water Samples

Table 4

Concentration of total iron in water samples and percent recoveries.

Sample	Iron added (mg L^−1)	Iron found (mg L^−1)	Recovery (%)
1	0	3.085	—
	1	4.151	106.6
	3	6.301	107.2
2	0	1.076	—
	1	2.111	103.5
	3	4.351	109.2
3	0	0.661	—
	1	1.751	109.0
	3	3.379	90.6
4	0	2.359	—
	1	3.398	103.9
	3	5.630	109.0
5	0	2.477	—
	1	3.446	96.9
	3	5.879	113.4
6	0	2.003	—
	1	2.976	97.3
	3	5.102	103.3
7	0	2.083	—
	1	3.108	102.5
	3	4.819	91.2
8	0	2.089	—
	1	3.037	94.8
	3	5.063	99.1