150K.Reddy-Nooneetal./J.Chromatogr.A1148(2007)145–151

Table1

DeterminationofiodideandbromideinthechloridematrixafterSDMEofderivatives(allresultsaretheaverageof vedeterminations)

Iodide(mg/100g)

LaboratorymadetablesaltsamplesSampleno.1cSampleno.2dSampleno.3eCommercialtablesaltsamplesRawsalt(India)

Sampleno.1(Spain)Sampleno.2(Spain)Sampleno.3(Spain)Sampleno.4(Tata)

Sampleno.5(NatureFresh)Sampleno.6(Star555)

Sampleno.7(CaptainCook)Sampleno.8(NirmaShudh)Sampleno.9(Knorr)Othersamples

Potassiumchloride(ThomasBaker)ConcentratedHCl(Merck)

abcdef

Recovery(%)ofspikea2.53.54.298.299.0101.697.598.497.2101.3102.098.198.297.5102.3

RSD(%)

Bromide(mg/100g)3.12.73.58.5830.1317.1828.8818.6613.2027.8030.6528.0824.7116.230.41

Recovery(%)ofspikeb

RSD(%)

1.964.869.870.490.045.075.862.622.183.522.602.832.900.44<LODf

5.1510.6015.363.52.73.54.03.63.93.13.74.23.73.85.1

99.0101.5102.198.597.498.997.998.298.6103.2101.498.5

1.82.52.91.61.82.02.23.62.81.92.44.2

2mgofiodide/100goftablesaltwasspiked.5mgofbromide/100goftablesaltwasspiked.

Thesamplecontained2mgofiodideand5mgofbromidein100gofsodiumchloride.Thesamplecontained5mgofiodideand10mgofbromidein100gofsodiumchloride.Thesamplecontained10mgofiodideand15mgofbromidein100gofsodiumchloride.Belowthelimitofdetection.

3.5.Analysisofrealsamples

Thepresentmethodhasbeenappliedtoseawaterandtablesaltsamplestodetermineiodide/iodateandbro-mide/bromate.Typicalchromatogramswereobtainedforanalysisofiodide/iodateandbromideinseawaterinvolv-ingsamplepreparationbySDME.Bromatewasnotfoundinseawater;possiblyitwasbelowtheLODinthesam-pleanalyzedbythepresentmethod.Similarobservationhasbeenmadebyusingarecentlyreportedmethodbasedonion

chromatography-inductivelycoupledplasma-massspectrome-try[45].3.6.Interferences

Theinterferenceofanumberofdifferentionshasbeenstud-iedbyspikingthestandardswithknownquantitiesofforeignsubstancesandanalyzingitbythepresentmethod.Anyorganicmatterthatalsoundergoesiodinationorbromination,suchasanilineandphenol,interferedseverelyandshouldberemoved,

Table2

Determinationofbromate/bromideandiodate/iodideinseawaterafterLPMEofderivatives(allresultsaretheaverageof5determinations)Sample

Iodide( g/l)Found

Seawaterno.1

25.6

Spiked10.020.030.025.050.075.025.050.075.0

Recoverya(%)97.8102.596.998.8105.799.0103.597.8101.9

Iodate( g/l)Found31.4

Spiked10.025.035.025.075.0100.025.050.075.0

Recoveryb(%)102.198.4104.396.897.9103.698.7103.698.6

Bromide(mg/l)Found60.8

Spiked15.025.035.025.050.075.030.060.075.0

Recoveryc(%)97.598.6103.6102.598.598.699.5105.198.5

Bromate( g/l)Found<LODe

Spiked5.020.030.010.025.075.025.050.075.0

Recoveryd(%)97.9104.296.7103.697.596.9104.699.2105.2

Seawaterno.215.236.555.4<LOD

Seawaterno.311.838.659.9<LOD

abcde

TheRSDwasintherange2.5–4.8%.TheRSDwasintherange3.6–5.4%.TheRSDwasintherange1.6–3.0%.TheRSDwasintherange4.2–6.5%.Belowthelimitofdetection.