Comparison of Three Solid Phase Materials for the Extraction of Carboxylic Acids from River Water Followed by 2D GC × GC-TOFMS Determination

Table 3

Raw and SPE filtered water characteristics.

Sample	SUVA = SAC/DOC (L/(mgm))	DOC (ppb)	Fractions of dissolved organic carbon (DOC) (in %)
			Hydrophobic DOC	Hydrophilic DOC	Building blocks	Low molecular weight acids (LMWAs)
Raw water	3.40	9106	7.3	92.7	12.2	NQ
Silica filtered water	2.88	1892	14.5	85.5	8.5	0.1
C-18 filtered water	1.37	6339	14.7	77	4.7	NQ
Strata X filtered water	2.93	1942	16.3	83.7	8.8	9.7

SUVA: specific ultraviolet absorbance.
SAC: spectral absorption coefficient.
DOC: dissolved organic carbon.