session: evaluating a rapid atmospheric pressure ... · • the appi-ms/ms analyzer developed...
TRANSCRIPT
Energy and Environment Knowledge
Week Congress – E2KW -
Session:
Evaluating a Rapid Atmospheric Pressure Photoionization -
Mass Spectrometry (APPI-MS) Method for the Detection of
Polychlorinated Dibenzodioxins (PCDD) and Furans (PCDF) in
Real Environmental Samples Collected within the Vicinity of
Industrial Incinerators
Rafael Cuesta – Mario Amo – Ross McCulloch
Project Objective
Application of a new analytical technique for the quantification of
dioxin, tracking continuous PCDDs/PCDFs concentrations in air,
soil and biota (vegetable matter) in the surroundings of a municipal
solid waste incineration facility.
Project outline
• Analyzer Definition
• APPI Ionization
• PCDD/F Limit of Detection
• Analysis Results
• Conclusions
• Next Steps
Analyzer definition: PCCD/PCDF isomer separation by ion mobility
DMA resolution was not adequate for isomer separation. A high resolution DMA is being developed by SEADM, but for the time being the DMA is not incorporated into the Analyzer:
Architecture of the APPI-MS
SEADM´s Custom APPI ion Source
Sciex´s Qtrap 3200 Triple Quadrupole MS
APPI Ionization: develop of a field-free APPI prototype
• SEADM´s ESI/SESI Sources are ideal for polars, but not
suitable for non-polars.
• SEADM´s APCI Source is suitable for non-polars, but did not
have enough sensitivity .
• A new field-free APPI Source has been developed with high
ionization efficiency for both polar and non-polar compounds.
Analysis
• Samples dissolved in toluene solvent infused into the nebulizer at 2µL/min
• Sample is vaporized in the nebulizer at 400⁰C using 99.999% N2 as nebulizer gas
• PCDD/PCDF ionization: [M-Cl+O]-
• Ions are transmitted to the MS using electric fields and analyzed in negative Multiple Reaction Monitoring mode.
PCDD/F Limit of Detection
• Analysis of air sampled blanks and air samples loaded with liquid standards • LODs ranging from 0.15 to 1.40 pg;
Homologues detected with a LOD around 1 pg
• Method used for comparison purposes:
NDAMN1 - (HR-GC-MS)
Air Sample Results
1,E-02
1,E-01
1,E+00
1,E+01
TCDD TCDF PeCDD PeCDF HxCDD HxCDF HpCDD HpCDF OCDD OCDFHo
mo
logu
e c
on
cen
trat
ion
s (p
g/N
m3)
PCDD/PCDF Homologue concentrations in air samples Monthly average
Location 1 Location 2
Soil Sample Results
1,E-01
1,E+00
1,E+01
1,E+02
1,E+03
TCDD TCDF PeCDD PeCDF HxCDD HxCDF HpCDD HpCDF OCDD OCDF
Ho
mo
logu
e c
on
cen
trat
ion
s (p
g/gr
)
PCDD/PCDF Homologue concentrations in soil samples Monthly average
Locat. 1 Locat. 2 Locat. 3 Locat. 4
Biota Sample Results
1,E-02
1,E-01
1,E+00
1,E+01
1,E+02
TCDD TCDF PeCDD PeCDF HxCDD HxCDF HpCDD HpCDF OCDD OCDF
Ho
mo
logu
e c
on
cen
trat
ion
s (p
g/gr
)
PCDD/PCDF Homologue concentrations in biota samples Monthly average
Locat. 1 Locat. 2 Locat. 3 Locat. 4
Discussion
• I-TEQ or WHO-TEQ can not be calculated since congener contribution to homologue results is unknown.
• Homogeneity between the levels of the different homologues suggests consistency in the results
• Location 4 shows the highest concentration levels in soil analysis, presumably due to contributions from the adjacent road traffic to the total PCDD/Fs concentrations.
• The high concentration levels of lower-chlorinated dioxins and furans (tetra and penta) obtained, are characteristic of incineration emissions, according to the prior studies of this emissions.
Conclusions
• The APPI-MS/MS analyzer developed allows detection limits around 1 pg for each PCDD/F homologue.
• Operational costs of the analyzer are considerably lower than present techniques: Cost per analysis ≈ 25 Euros.
• According to project plan, the Analyzer will be improved at the end of 2016 with a high resolution DMA, which will allow isomer separation.
Next Steps: Interferent and isomer separation by
Ion Mobility Mass Spectrometry
•Nanoparticles and ion separation depending on their electrical mobility.
•Fluid velocity (horizontal) = U and Electrical velocity (vertical) = Z x E.
•Ion trayectories depends on Z, leaving the DMA only ions with Z= UΔ2/LV
Planar Differential Mobility Anlyzer
DMA P5
Next Steps: Interferent and isomer separation by
Ion Mobility Mass Spectrometry
DMA advantages over other separation techniques.
•Mobility separation is carried out in miliseconds versus dozens of minutes of other techniques such as gas chromatography.
•DMA ion transmission is remarkably high, in the order of 50%.
•The DMA substantially reduces the chemical noise since it only allows passing one electrical mobility at a time.
•DMA resolution are high compared with other ion mobility techniques such as FAIMS.
•Ion mobility separation takes place at atmospheric pressure.
•All the previous features allows an easily integration of SEADM DMA with the majority of mass spectrometers in the market.
Next Steps: Interferent and isomer separation by
Ion Mobility Mass Spectrometry
SEADM is working in a new HR-DMA which doubles the resolution of the previous version.
Sign
al in
ten
sity
cp
s
DMA voltage (inversely proportional to ion mobility)
Preliminary results working with PAHs, shows that the HR-DMA with the help of a deconvolution algorithm allows the separation BaP and BeP from a mixture of both standards.
