Figure 4.

MID calculation of glutamine M5 obtained from labeled A549 cell extract diluted in plasma (0.1, 0.2, 0.5, and 1% of the original ¹³C enrichment) with (gray) and without model peak correction (red)—(a) Barplot of calculated (saturated) and estimated (transparent) glutamine M5 abundance with (gray) and without (red) model peak correction; (b) scatter plot of estimated vs measured glutamine M5 abundance, with (gray) and without (red) model peak correction for linear regression analysis.