Applying Four-Step Characteristic Ion Filtering with HPLC-Q-Exactive MS/MS Spectrometer Approach for Rapid Compound Structures Characterization and Major Representative Components Quantification in Modified Tabusen-2 Decoction

Table 2

Calibration curves, linear range, r², and LOQs of 19 compounds in MTBD.

Compound	Calibration curves	Linear range (μg/mL)	r^2	LLOQ (μg/mL)
ICGAA	y = 647.937x + 1.476	4.800–192.000	0.9994	4.800
1,5-DQA	y = 364.018x − 0.810	6.100–244.000	0.9991	6.810
GE	y = 22386.297x − 0.191	0.023–0.920	0.9982	0.025
APG	y = 29960.140x − 0.562	0.065–2.600	0.9989	0.073
LT	y = 15454.517x − 0.090	0.015–0.600	0.9986	0.015
KPF	y = 9208.139x − 0.051	0.010–0.400	0.9983	0.010
QC	y = 8437.051x − 0.062	0.011–0.440	0.9989	0.011
A-7-O-G	y = 6901.196x + 11.968	4.200–168.000	0.9962	4.200
RU	y = 2560.803x − 0.093	0.230–9.200	0.9992	0.250
HSYA	y = 1104.734x − 0.935	9.830–392.000	0.9984	10.930
NG-R1	y = 8.300x − 0.016	2.400–96.000	0.9964	2.400
G-Re	y = 730.821x + 0.137	1.010–40.400	0.9963	1.010
G-Rg1	y = 21.700x + 0.029	6.500–260.000	0.9983	6.700
G-Rb1	y = 93.320x + 0.128	5.660–226.400	0.9979	5.830
CA	y = 183840.263x − 8.999	0.260–10.400	0.9985	0.260
FA	y = 2322.874x − 0.525	0.390–15.600	0.9992	0.410
GPA	y = 119.544x − 0.011	0.800–32.000	0.9987	0.800
CGA	y = 3414.355x − 5.245	5.500–220.000	0.9978	5.660
PDG	y = 10.556x − 0.018	2.180–87.200	0.9987	2.180