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 1

Colorimetric test results.

Methods	Positive/Negative	Colour observed
Ferric test	+	Greenish-brown
Shinoda’s test	+	Brown
Acid butanol test	+	Crimson
Nitrous acid test	−	Brownish-yellow
Potassium iodate test	−	Brown

+ positive test, − negative test.