Table 3. Quantitative aspects of isotope-labeling derivatization^a.

Carboxylic acid	m/z		Derivatization limit (μM)	Linearity
	Light form	Heavy form		Correlationb	Dynamic rangec
Oxaloacetic acid, di-	213.36	222.32	50	y=0.892x, r2=0.997	1:1∼1:5
Oxalic acid, di-	192.25	201.26	50	y=0.925x, r2=0.995	1:1∼1:5
Malonic acid, di-	199.33	208.34	25	y=1.124x, r2=0.999	1:1∼1:8
Fumaric acid, di-	205.37	214.38	10	y=0.935x, r2=0.995	1:1∼1:10
Succinic acid di-	206.36	215.36	5	y=1.085x, r2=0.999	1:1∼1:50
Maleic acid, di-	205.38	214.38	10	y=0.943x, r2=0.997	1:1∼1:10
Malic acid, di-	214.37	223.37	5	y=0.914x, r2=0.992	1:1∼1:50
Citric acid, di-, -H2O	234.33	243.34	10	y=0.967x, r2=0.993	1:1∼1:10
a-ketoglutaric acid, di-	220.38	229.33	25	y=0.907x, r2=0.993	1:1∼1:10
isocitric acid, di-, -H2O	234.33	243.34	25	y=0.975x, r2=0.990	1:1∼1:10
Tartaric acid, di-	222.36	231.35	10	y=0.843x, r2=0.996	1:1∼1:10
Adipic acid, di-	220.57	229.56	5	y=1.142x, r2=0.999	1:1∼1:50
Citric acid, di-	243.33	252.34	10	y=1.135x, r2=0.999	1:1∼1:10
isocitric acid, di-	243.33	252.34	10	y=1.112x, r2=0.994	1:1∼1:10
Formic acid	193.32	202.34	10	y=1.201x, r2=0.978	1:1∼1:10
Acetic acid	207.33	216.34	25	y=0.956x, r2=0.997	1:1∼1:10
Propionic acid	221.37	230.33	5	y=1.230x, r2=0.999	1:1∼1:50
Pyruvic acid	235.37	244.34	25	y=1.160x, r2=0.992	1:1∼1:8
Lactic acid	237.34	246.36	25	y=1.109x, r2=0.993	1:1∼1:8
Butyric + isobutyric acid	235.33	244.34	5	y=0.871x, r2=0.996	1:1∼1:50
Benzonic acid	269.33	278.33	5	y=1.063x, r2=0.999	1:1∼1:50
Shikimic acid	321.36	330.38	25	y=1.231x, r2=0.996	1:1∼1:8
Quinic acid	339.35	348.37	100	nd	nd

^aAnalytes were derivatized with BAMP and BAMP-d9.

^by= experimental mass spectrometric peak intensity ratio of light form to heavy form; x= theoretic ratio.

^cDetermined by keeping the light form concentration constant (100mM) and reducing the heavy form concentration.

^dNot detected.