Table 1. NMR Integration Regions and Concentration Ranges Used for Investigation of LOD, LOQ, and Linearity.

compound	NMR range	working range (mg/L)	LOD/LOQ range (mg/L)
caffeine	7.93–7.87 ppm (singlet)	1–200	1–16
aspartame	3.11–3.03 ppm (multiplet): with citric acid	3–350	3–10
	2.76–2.73 ppm (doublet): without or few citric acid	4–350	4–100
acesulfame-K	5.70–5.65 ppm (quadruplet)	1–300	1–10
cyclamate	2.01–1.92 ppm (multiplet)	2–244	2–9
benzoate	7.62–7.56 ppm (multiplet)	2–210	1–42
E 150D	2.23–2.21 ppm (singlet)	41–2500	41–300
HMF	9.46–9.45 ppm (singlet)	1–10	1–5
vanillin	9.73–9.72 ppm (singlet)	1–20	1–10