Simultaneous gas-chromatographic analysis of lower fatty acids, phenols and indoles in faeces and saliva using a fused silica glass capillary column

Abstract

The simultaneous gas-chromatographic separation of a mixture of 14 lower fatty acids, 11 phenols and 7 indoles was performed by using a fused silica glass capillary column of Carbowax 20M (50m x 0.2mm i.d., Carbowax 2OM deactivated). Complete separation of the mixture was obtained, except for the peaks of phenols and o-cresol, o-ethylphenol and 3,5-xylenol and pelargonic acid, 2,3-xylenol and 1,2-dirnethylindole, whose peaks overlapped, and 2-and 3-methylindoles, which were poorly separated. The optimum conditions are as follows: column temperature, held for 1 min a t 100 "C; column oven, heated a t 4 "C min-1 from 100 to 220 "C, maintained at 220 "C for 9 min for standard compounds or 29 min for sample specimens, then cooled to 100 "C; and carrier gas (nitrogen) flow-rate, 0.97 ml min-l. The method was applied to the analysis of the lower fatty acids, phenols and indoles in cat and human faeces and non-smoker saliva.

Simultaneous Determination of Phenol and Mononitrophenol Isomers Using PLS Regression and Conventional and Derivative Spectrophotometry

“…However, some sample pre-treatments involving separation, extraction and/or adsorption are generally necessary, and these have been time-consuming and complex. The simultaneous determination of several phenols in the same sample can be carried out by voltammetry 31 and chromatographic methods including GC [32][33][34] and HPLC. [35][36][37][38] Simultaneous determination of several phenolic compounds by spectrophotometric methods has also been reported.…”

A Newly Designed Deodorant Pad for Urinary Incontinence

“…The fiber of iron‐phthalocyanine effectively eliminated bad‐smelling gases in vitro. These bad‐smelling substances in the environment are offensive to the nose in a concentration of less than 1 ppb in air 3 . In a much higher concentration the fiber of iron‐phthalocyanine eliminated in vitro a much larger amount of the bad‐smelling substances than activated carbon did.…”

“…This is why leaked urine in a diaper smells of ammonia. Fecal incontinence gives off the smells of acetic acids, indole, skatole, and other compounds 3 …”

Method for the determination of indole and skatole in pig fat

“…Packed column chromatography gave good resolution for macro quantities of the analytes, as in the case of gut contents, but when scaled down to sub-microgram kg-' fat levels there was poor separation from interfering compounds. This problem has been overcome by some workers by using fused silica glass capillary columns (Hoshika and Murayama 1983;Peleran and Bories 1985;Garcia-Regueiro et a1 1986a). Others have used spectrophotometric methods based on Chernoff's modification of the Ehrlich reaction of indoles with p-dimethylamine-benzaldehyde (Myers 1950;Cant and Walker 1980;Mortensen and Sorensen 1984).…”