Hiroya Harino

Simultaneous determination of butyltin and phenyltin compounds in the aquatic environment by gas chromatography

Abstract A method for the simultaneous determination of butyl- and phenyltin compounds in the aquatic environment was studied. The analytes in water, sediment and biological samples were extracted into 0.1% tropolone-benzene solution after adding hydrochloric acid diluted with tetrahydrofuran. With sediment samples, inorganic sulphur-containing species co-extracted with the analytes were removed with tetrabutylammonium hydrogensulphate-sodium sulphide, which brought about a decrease in many of the accompanying peaks. After propylation with n-propylmagnesium bromide, the analytes were determined by gas chromatography with flame photometric detection. The recoveries were in the range 70–100% and the detection limits for a signal-to-noise ratio of 10 were 3 ng 1−1 in water samples and 0.5 μg kg−1 in sediment and biological samples.

Analysis of organotin compounds by grignard derivatization and gas chromatography-ion trap tandem mass spectrometry.

The determination of organotin compounds in water using gas chromatography-tandem mass spectrometry (GC-MS-MS) is described. Several organotin derivatives were synthesized by the reaction of organotin chlorides with Grignard reagents such as methyl-, propyl- and pentylmagnesium halides. After the optimization of the GC-MS-MS conditions, several derivatizations with the Grignard reagents were compared by evaluating the molar responses and volatilities of the derivatives and derivatization yields. As a result, the derivatizing reagent of choice is pentylmagnesium bromide. Calibration curves for the mono-, di- and tributyltins and mono-, di- and triphenyltins with pentylmagnesium bromide were linear in the range of 0.5-100 pg of Sn. The instrumental detection limits of six organotins ranged from 0.20 to 0.35 pg of Sn. The recovery tests from water samples (500 ml) were performed by using sodium diethyldithiocarbamate (DDTC) as a complexing reagent. Except for monophenyltin, the absolute recoveries of organotins from pure water at 200 ng of Sn/l were satisfactory. The recoveries calibrated by surrogate compounds (perdeuterated organotin chlorides) ranged from 71 to 109%. The method detection limits ranged from 0.26 to 0.84 pg of Sn (500-ml sample). This method was applied to the recovery of organotins from river water and seawater. The calibrated recoveries were between 90 and 122%.

Double-chain surfactants with two sulfonate groups as micelle-forming reagents in micellar electrokinetic chromatography of naphthalene derivatives

Three surfactants having two sulfonate groups and two lipophilic chains, disodium 5,12-bis(dodecyloxymethyl)-4,7,10,13-tetraoxa-1-16-hexadecanedisulfonate (DBTHX), 5,13-bis(dodecyloxymethyl)-4,7,11,14-tetraoxa-1-17-heptadecanedisulfonate (DBTHP) and 5,13-bis(dodecyloxymethyl)-4,7,11,14-tetraoxa-9,9-dimethyl-1-17-heptadecanedisulfonate (DBTDMHP), were used in micellar electrokinetic chromatography (MEKC) to separate eight naphthalene derivatives as model analytes. Their capacity factors linearly increased as the concentration of each surfactant increased from 1 to 10 mM at pH 7.0. These double-chain surfactants exhibited different selectivity and wider migration time windows when compared with sodium dodecyl sulfate (SDS), which is used widely in MEKC. The eight naphthalene derivatives were baseline separated at 5 mM DBTHX and 2.5 mM DBTHP, respectively, and nearly baseline separated at 2.5 mM DBTDMHP. However, SDS at 60 mM could not completely resolve three of the analytes.

Determination of aromatic amine mutagens, PBTA-1 and PBTA-2, in river water by solid-phase extraction followed by liquid chromatography-tandem mass spectrometry.

We describe a novel method for the determination of two kinds of aromatic amine mutagens, 2-[2-(acetylamino)-4-[bis(2-methoxyethyl)-amino]-5-amino-7-bromo-4-chloro-2H-benzotriazole (PBTA-1) and 2-[2-(acetylamino)-4-[bis(2-cyanoethyl)-ethylamino]-5-amino-7-bromo-4-chloro-2H-benzotriazole (PBTA-2), in river water based on liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS-MS). A solid-phase extraction procedure was used for the extraction of PBTA-1 and PBTA-2 from river water. The procedure was rapid and the relative standard deviations were below 4%. The detection limits of PBTA-1 and PBTA-2 in river water using the proposed method were found to be 1 and 2 ng/l, respectively. The compounds were detected by this method in river water taken from two sites in the Yodo River system at the ng/l level.

Simultaneous determination of 2-phenylbenzotriazole-type mutagens, PBTA-1 through -8, in river water by liquid chromatography–tandem mass spectrometry

We describe a method for the simultaneous determination of eight kinds of phenylbenzotriazole-type mutagens (PBTA-1, -2, -3, -4, -5, -6, -7 and -8) in river water based on liquid chromatography-tandem mass spectrometry (LC/MS/MS). The application of dopant-assisted atmospheric pressure photoionization (APPI) for the detection of the PBTAs was studied. The APPI technique provided higher PBTA signal intensities than those obtained with an electrospray ionization (ESI) source, and the APPI method was used for the determination of the PBTAs. A solid-phase extraction procedure was used for the extractions of PBTA-1 through -8 from river water. The procedure was rapid and the relative standard deviations were below 15%. The detection limits of PBTA-1 through -8 in river water using the proposed method were found to range from 0.04 to 0.5 ng L(-1) and PBTAs were successfully detected in river water at sub-ng L(-1) levels.

Reversed-phase liquid chromatography of polar benzene derivatives on poly(vinylbenzo-18-crown-6)-immobilized silica as a stationary phase

Abstract A packing in which poly(vinylbenzo-18-crown-6) is immobilized covalently to silica was tested for its usefulness as a stationary phase in the reversed-phase liquid chromatography of polar disubstituted benzene derivatives. Both electrostatic and hydrophobic interactions contribute considerably to the chromatographic separation. When potassium cations, which are complexed by the crown ether moiety on the stationary phase, are added to the mobile phase during chromatography using the poly(crown ether)-immobilized silica, positive charges are generated on the surface of the stationary phase and some electrostatic interaction occurs between polar disubstituted benzene derivatives and the stationary phase. Hence the retention behaviour of polar organic compound can be controlled easily by adding metal cations to the mobile phase. This type of reversed-phase chromatography using poly(crown ether)-immobilized silica is useful for separating positional isomers of various disubstituted benzene derivatives.

Separation of naphthalene and flavone derivatives by micellar electrokinetic chromatography with double- and triple-chain surfactants.

Three surfactants, p-bis(2-dodecyloxymethyl-3-oxa-6-sodiosulfonatohexyloxy)benz ene (BDSB) having two sulfonate groups and two lipophilic chains, disodium 10-dodecanoyl-5,15-bis(dodecyloxymethyl)-10-aza-4,7,13,16-tetra oxa-1,19-nonadecanedisulfonate (DDBTN) having two sulfonate groups and three lipophilic chains and disodium 4,11-bis(dodecyloxymethyl)-3,6,9,12-tetraoxa-1,14-tetrade canedionate (DBTT) having two carboxylate groups and two lipophilic chains, were used in micellar electrokinetic chromatography (MEKC). Eight naphthalene derivatives were baseline separated at 10 mM BDSB or 5 mM DBTT, and five flavone derivatives at 5 mM BDSB, DDBTN or DBTT. The elution order of the naphthalene derivatives in MEKC with BDSB was identical with that with DDBTN. However, this elution order was different from that found with DBTT. In the case of the flavone derivatives, BDSB, DDBTN and DBTT produced the identical elution order. These double- and triple-chain surfactants exhibited different selectivity when compared with widely used sodium dodecyl sulfate.