Reevaluation of headspace solid-phase microextraction and gas chromatography–mass spectrometry for the determination of methyl tert-butyl ether in water samples

Simultaneous determination of ten taste and odor compounds in drinking water by solid-phase microextraction combined with gas chromatography-mass spectrometry

“…It has been reported that high temperature can have undesirable effects on the extraction efficiency of SPME fibers for some low molecular weight analytes with higher volatility because adsorption of analytes by the fiber coating is an exothermic process (Fang et al, 2003;Burbank and Qian, 2005;Vichi et al, 2005). However, in this study, a definite increase in total peak area occurred when the temperature increased from 35 to 65°C (Fig.…”

Trace analysis of methyl tert-butyl ether in water samples using headspace solvent microextraction and gas chromatography–flame ionization detection

“…To obtain the final concentration of MTBE in the microdrop, it was injected to GC and the area of resulting signal was used to determine its concentration from a calibration graph obtained, from the direct injections of varying concentration of the sample under the same experimental conditions. Very recently, using a SPME method, Fang, et al, have shown that the presence of BTEX will result in the diminished extraction efficiency of MTBE [31]. In order to examine the influence of BTEX on the extraction of MTBE by the proposed method, the extraction of 20 g/l of MTBE was performed in the presence and absence of 100 and 200 g/l of o-xylene.…”

“…As the concentration of a mixture of analytes is increased, the sites will eventually become occupied. At this point no more samples will be adsorbed, or else displacement will occur [31].…”

“…This is most probably due to the fact that, in the proposed HSME method, the extraction inside microdrop is based on distribution while, in the SPME adsorption and distribution can occur, it is depend of the SPME coating. For instance, Crboxen-polydimethylsiloxane (CAR-PDMS) extracts MTBE via adsorption [31]. For adsorbent-type fibers, the number of sites or pores is limited.…”

Single-walled carbon nanotubes as an effective adsorbent in solid-phase microextraction of low level methyl tert-butyl ether, ethyl tert-butyl ether and methyl tert-amyl ether from human urine

“…It is interesting that the peak areas increased with the addition of NaCl (1.5 M), so 0.87 g NaCl was added to the urine sample (10 mL) to adjust the ionic strength in the following experiments. The same experiments were carried out with CAR/PDMS fiber which is frequently used for determination of oxygenated ethers [51,52] and the optimum condition for extraction of the ethers was determined as follow: extraction time, 25 min; extraction temperature, 40 • C; desorption time, 3 min; desorption temperature, 250 • C; salinity, 2.5 M NaCl.…”