A Simple Automated Method for the Determination of Nitrate and Nitrite in Infant Formula and Milk Powder Using Sequential Injection Analysis

Table 2

Routine for determination of nitrate by reduction to nitrite. V₁, V₂, S, HC₁, HC₂, Cd/Cu, R₁, C₁, Sy, W, and D: as indicated in Figure 1. X: not relevant. R: right. L: left. A: aspirate. P: propel. DAQ: step involving data acquisition.

Step	V1	V2	Operation	Destination	Volume (𝜇L)	Time (s)
1	S	L	A	HC1	40	1
2	Cd/Cu	L	P	Cd/Cu	40	34
3	X	R	A	Sy	250
4	Cd/Cu	L	P	Cd/Cu-HC2	250
5	Cd/Cu	L	A	HC1	167
6	W	L	P	W	167	10
7	X	R	A	Sy	1940
8	R1	L	A	HC1	100	1.5
9	Cd/Cu	L	A	HC1	210	15
10	C1	L	P	C1	400	14
	C1	L	A	HC1	400
11 (DAQ)	C1	L	P	D	Empty syringe	35