Environmental Engineering Reference
In-Depth Information
extraction (LLE), solid-phase extraction (SPE) or solid-phase microextrac-
tion (SPME) of the derivatizated compounds; and (ii) LLE with non-polar
solvents [toluene, dichloromethane (DCM)] alone or in mixture with or
without complexing agents and in the presence or not of acidic condi-
tions and subsequent derivatization with Grignard reagents. After derivati-
zation, gas chromatographic separation followed by different detection tech-
niques such as mass spectrometry (GC-MS), tandem mass spectrometry
(GC-MS-MS) or flame photometry (GC-FPD) for the determination of the
species [18-21].
Martinez Vidal et al. [22] compared the use of LLE (using DCM, hex-
ane, diethyl ether, acetone, acetonitrile and their different mixtures) and solid
phase extraction (SPE) for the determination of eight organotin compounds
(MBT, DBT, TBT, TeBT, MPhT, DPhT, TPhT and TePhT), with a spiking ex-
periment, using DDTC (diethyldithiocarbamate) as the complexing agent.
With LLE low recoveries were obtained for all the compounds except for MBT,
but then the high values of MBT proved to be due to some interfering com-
pound. With the SPE method, good recovery values were achieved, but no
further details on recovery evaluation were reported in the paper. Tessier et al.
studied the extraction of volatile tin compounds from marine water by cryo-
genic trapping-GC-ICP-MS [23]. The high sensitivity and selectivity of the
ICP
MS detector coupled with cryofocusing assured detection limits below
1 fmol L
-1
as tin. Følsvik et al. [24] studied whether semipermeable mem-
brane devices (SPMDs) are applicable to monitor organotin compounds in
the marine environment with time-integrated sampling. Triolein, one of the
main components of neutral lipids in numerous aquatic organisms, suitable
for concentrating organic contaminants, was used to fill the SPMD tubing
/
Table 1
Applied speciation steps for organotin determination in marine water reported in
papers published since 2000
Extraction
Derivatization
Preconcentration
Analysis
•
LLE:
•
hydride generation
•
SPME
•
GC-MS [18]
- DCM [21, 22]
[19]
•
cryogenic trap [23]
•
GC-MS
/
MS
- hexane [18, 22]
•
organoborate:
[20, 22]
- toluene [20]
- ethylation [18, 24]
•
GC-FPD [19, 21]
- diethylether [22]
•
Grignard:
•
GC-ICP-MS [23]
- acetone [22]
- pentylation [20, 22]
•
GC-AED [24]
- acetonitrile [22]
- propylation [21]
- mixtures [22, 24]
•
SPE [22]
•
SPMDs [24]
