an evaluation of a particle beam interface at high aqueous

An Evaluation of a ParticleBeam Interface at High

Aqueous Concentrations

Jennifer M. Duker and Thomas C. Marecic

Problem...

Reverse phase HPLC can typically include highaqueous solvent conditions.

MS is becoming a preferred detection device forHPLC.

Compatibility between the two techniques ischallenging.

Stages of Particle Beam LC/MS

HPLC INTERFACE MASSDETECTOR

Phase Momentum

LC Separate Separate MSLiquid _ "- "- _ GasPhase Phase

INTERFAC

Phase Momentum

Separate Separate

Aerosol Enrichment/generation Pressure

ReductionDesolvation

Phase Separation

GoalTo separate the solvent from thesolute by converting the solvent tothe gas phase and the solute t°particles

° Nebulization - generation of anaerosol

° Desolvation - separation of thesolvent from the solute

Momentum Separation

,-GoalTo remove gas phase whiletransporting particles into MS

° Effective removal of solvent• Enrichment of solute

INTERFACE

Phase Momentum

Separate Separate

Aerosol Enrichment/generation Pressure

ReductionDesolvation

Why are some solvent conditionsmore difficult?

Solvent B.Pt.

ProticWater 100 10.5Methanol 64.7 8.9

AproticAcetonitrile 81.6 7.8THF 66.0 7.6

Phase Separation(Cpdt)g+(Cpdt)soI

(Cpdt)l AHvap

TOcmeasured iDEAL

Power (watts)

100% Solvent Evaporation0% Solute Evaporation

Summary of Phase SeparationTM

ThermaBeam

Thermal/Pneumatic NebulizationDesolvation

Analysis of Environmental CompoundsExperimental Conditions

Analytical ConditionsCompounds: caffeine

methomylbenzidine

Column: Waters Nova-Pak C18 (2.0 x 150 mm)Mobile Phases: (1)72:28 ammonium acetate:ACN

(2)87:13 ammonium acetate:ACNFlow rate: 250 uL/min

MS Review

Ivent Conditions72:28

NH4OAc:ACN

MaxplotChromatogram

100 to 200 amu

PDA Review

Fi p

HighAqueousSolvent

Conditions87:13

NH OAc:ACN4

MS Review

HighAqueousSolvent

Conditions87:13

NH4OAc:ACN

View Cube

3D

Chromatogram

TICContour View

MaxplotChromatogram

Maxplot Chromatogram100 to 200 amu

Environm

Overlay of Mass Spectra

_ra::_i!_!_ii_i__Hel:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

•Eile',"_!!i_'_i_!_E_ditl;ii__!_PlOt_D,C p

ExtractedMass

Spectrumof methomyl

__Hetp!!i

Extracta

Mass

Spectrumof

benzidine

ExtractedMass

Spectrumof benzidine

Extracta

Mass

Spectrumof

caffeine

ExtractedMass

Spectrumof caffeine

Conclusions

Analysis using high aqueoussolvent conditions is possible

,_ThermaBeam TM lessens the

challenge for compatibility betweenHPLC and MS

AutoOptimize adjusts the interfaceto handle high aqueous conditions