The Use of Silver Solid Amalgam Electrodes for Voltammetric and Amperometric Determination of Nitrated Polyaromatic Compounds Used as Markers of Incomplete Combustion

Table 6

Parameters of calibrations dependences for the determination of 5-NQ, 2-NF, 1-NP, and 3-NFt using HPLC-ED with “wall-jet” m-AgSAE detector (A) under optimized conditions in deionized water as an ideal matrix and (B) for determination in drinking water after SPE. Mobile phase 0.01 mol L⁻¹ phosphate buffer pH 7.0: methanol (15 : 85; v/v), 𝐹_𝑚=1 mL min⁻¹, 𝑉_inj=20 μL, detection potential −1.5 V, responses evaluated from the peak heights.

	Analyte	Linear dynamic range (μmol L^−1)	Slope^a	Intercept^b	Correlation coefficient	𝐿𝐷 (μmol L^−1)
(A) Optimized conditions in deionized water
Electrochemical detection	5-NQ	10–75	–1.28	–0.6	–0.9972	8.9
	2-NF	25–100	–1.45	–2.1	–0.9798	7.8
	1-NP	25–100	–0.91	–15.5	–0.9935	12.5
	3-NFt	25–100	–1.00	1.0	–0.9985	11.4
UV detection	5-NQ	1–100	0.502	–0.12	0.9999	1.6
	2-NF	1–100	0.423	–0.19	0.9998	1.9
	1-NP	1–100	0.882	–0.39	0.9999	0.9
	3-NFt	1–100	0.943	–0.12	0.9999	0.8
(B) Determination in drinking water after SPE
Electrochemical detection	5-NQ	0.5–5	–25.9	2.3	–0.9997	0.66
	2-NF	2–10	–20.7	–13.0	–0.9957	0.83
	1-NP	2–10	–20.3	–15.2	–0.9823	0.84
	3-NFt	2–10	–16.0	7.8	–0.9766	1.1
UV detection	5-NQ	0.5–10	10.2	–4.0	0.9829	0.38
	2-NF	0.5–10	8.0	–4.2	0.9937	0.50
	1-NP	0.5–10	16.0	–3.1	0.9940	0.24
	3-NFt	0.5–10	21.2	–5.0	0.9882	0.18

^a For electrochemical detection in nA μmol⁻¹ L and for spectrophotometric detection in mA.U. μmol⁻¹ L.
^b For electrochemical detection in nA and for spectrophotometric detection in mA.U.