Table 2.

Operating parameters of GC–MS.

Column	DB-5MS capillary column
	(30 m × 0.25 mm; 0.25 μm; Thermo Scientific, USA)
GC oven conditions	50 °C, hold 5 min
	10 °C/min to 65 °C, hold 30 min
	5 °C/min to 120 °C, hold 10 min
	5 °C/min to 180 °C
	5 °C/min to 210 °C, hold 10 min
	20 °C/min to 325 °C, hold 10 min
Carrier gas	He (1 mL/min, 25 psi)
Linear velocity	19.8 cm/s
Injection mode	Split 1:20
Injection temperature	250 °C
MS parameters		FID parameters
MS ionization mode	EI	FID temperature	300 °C
Scan time	0.2 s	Hydrogen flow	35.0 mL/min
Mass range	35–550 amu	Air flow	350.0 mL/min
Ion source temperature	270 °C	Make up flow	40.0 mL/min
Interface temperature	250 °C