multi-element single particle analysis by icptof€¦ · 19 2017.08.02 webinar –multi-element...

Multi-Element Single Particle Analysis by icpTOF

Olga Borovinskaya

TOFWERK AG, Switzerland

2017.08.02 Webinar – Multi-element single particle analysis2

SP-ICP-MSNanolytics

Hassellöv and Kägi, et al., 2009, John Wiley & Sons, Ltd, 211-266


SP-ICP-MSNanolytics

Hassellöv and Kägi, et al., 2009, John Wiley & Sons, Ltd, 211-266


Analyte mass <--

Particle number

concentration <--

SP-ICP-MSSingle particle ICP-MS

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.80

2

4

6

8

10

12

14

16

18

20

Sig

nal (

a.u.

)

Time (ms)

0 1 2 3 4 5 6 7 8 9 100.0

0.2

0.4

0.6

0.8

1.0N

orm

aliz

ed s

igna

l (a.u

.)

Time (ms)Time (s)

C. Degelerde et al., Colloids Surf., A, 2003, 217, 137-142


CalibrationCalibration strategy

• Assumption - particles and

solutions behave the same

• in sample introduction system

• in plasma

• Challenge - mass of analyte

entering the plasma per time is

not known

Transport efficiency

• Picture from D. M. Mitrano, et al., Environmental Toxicology and Chemistry, 2012, 31(1):115-21

• H.E. Pace, et al., Anal. Chem., 2011, 83, 9361-9369


CalibrationTransport efficiency measurement

• Waste collection method does not work

• Two methods proposed by Pace et al. are used

• Based on known particle size

• Based on known particle number concentration

• Most commonly used method is size-based with Au NPs from NIST

Au

Au

𝑻𝒓𝒂𝒏𝒔𝒑𝒐𝒓𝒕 𝒆𝒇𝒇𝒊𝒄𝒊𝒆𝒏𝒄𝒚 (%) =𝑴𝒂𝒔𝒔 𝑨𝒖𝒎𝒆𝒂𝒔𝒖𝒓𝒆𝒅

𝑴𝒂𝒔𝒔 𝑨𝒖 𝒊𝒏𝒕𝒓𝒐𝒅𝒖𝒄𝒆𝒅

Particle size method

• Picture from D. M. Mitrano, et al., Environmental Toxicology and Chemistry, 2012, 31(1):115-21

• H.E. Pace, et al., Anal. Chem., 2011, 83, 9361-9369


SP-ICP-MSSingle particle detection

• Only one isotope per particle

• Only single-element particles

Quadrupole

Sector-field


TOFMulti-element single particle detection

• All isotopes every 30 µs

• All isotopes from an individual particle

• Complex particles, complex samples

Time-of-flight


icpTOFicpTOF for single particle detection

• NPs detection limits 10-100 nm*

• Mass resolving power**

• 3000 for icpTOF

• 6000 for icpTOF 2R

• Q-cell for interference control

• Matrix ion removal with notch filter

• Mass accuracy of 5 mTh

* Estimated for pure metallic particles

** Defined as m/Δm, where Δm is FWHM of the peak of

mass m

L. Hendriks et al., JAAS, 2017, 32, 548-561


icpTOFicpTOF for single particle detection


SP-icpTOFMulti-element single particle detection

• Sensitivity does not depend on number of measured isotopes

• Isotope ratios are accurate

• No need to choose what to measure prior to the analysis

• Sensitivity decrease with the number of measured isotopes

• Isotope ratios are biased

• Currently max 2 isotopes per particle

Simulated data


SP-icpTOFChallenging particles with icpTOF

NPs Bestisotope

Interferences Resolvingpower(m/Δm)*

Fe2O356Fe 40Ar16O 5000

SiO228Si 28N2 2000

TiO248Ti 32S16O, 12C36Ar 5000

XS 32S 32O2 3600

*Bodo Hattendorf, 2002, DISS. ETH NO. 14926Numbers given with Δm as full width at 10% of peak maximum were converted to FWHM

Mass resolving powericpTOF 3000

icpTOF 2R 6000

Q-cellInert gas collisional ion focusing

Reactive gas specific reaction H2 example


ApplicationsComposition of steel nanoparticles

Sample:

Synthetic nanosteel platelets (NanoDefine Project)

Method:

icpTOF with H2 in Q-cell to improve Fe detection limits

Calibration:

Sensitivity ratios with multi-element solution standards

Element composition calculated using 100% normalization

Collaboration work with S. Böhme, R. Peters, RIKILT, The Netherlands

• Size is very polydisperse, but the ratios are not• Element composition determined with solution only

Element Expected Measured molar fraction*

Fe 67-72% 68 ± 5%

Cr 16-26% 19 ± 4%

Ni 10-14% 11 ± 3%

Mo 2-4% 1.3 ± 0.4%

* Error is the SD from 2000 single particles


ApplicationsEngineered nanoparticles in the environment

Challenge

• CeO2, TiO2, SiO2, Al2O3, CuO, ZnO

• Elements are present in the

environment at high concentrations

• Elements are not homogeneously

distributed, in form of natural NPs

• Engineered particles at very low

levels

• Lack of techniques to discriminate

Solution

• Single particle fingerprinting


ApplicationsCeO2 nanoparticles in soil

C: 0.06D: 0.6E: 6

Important findings

• Enables tracing engineered CeO2

• Detection limit far below natural

background

• Does not require labeling

• Provides new information about

particulate natural background

Concentration factors ENP/NNP

Picture from A. Praetorius et al., Environ. Sci. Nano., 2017,4, 307-314

O: blankA: 0.0006B: 0.006


ApplicationsTiO2 NPs from sunscreens in lake water

Background

• Ti concentration and Ti:Al ratio in bulk increase during bathing season*

• Number concentration of Ti-bearing particles increases as well

icpTOF results

• In individual particles only Ti:Mn and Ti:Pb changed

• Elemental ratios in single particles are different from bulk

• Big fraction of natural NPs are pure Ti

Other elements associated with Ti: Fe, Mn, Pb

Collaboration with A. Gondikas, F. von der Kammer, Department of Environmental Geosciences, University Vienna*A. Gondikas, et al. Environmental Science and Technology, 2014, 48, 5415-5422


ApplicationsIn vivo formation of HgSe

Background*

• Se protects the body from toxic MeHg

forming HgSe

• Mechanism of formation is still poorly

understood

• Study on a population of stranded pilot

whales

• SP-ICP-QMS revealed increase in HgSe

size and concentration with age

• Synchrotron µ-XRF showed Hg:Se of 1 in

large clusters and < 1 in small

* Z. Gajdosechova, et al., Sci. Rep., 2016, 6, 34361

Hg:Se = 1

Hg:Se < 1

Synchrotron µ-XRF imaging with 800 nm pixel size

SP-ICPQMS of liver and brain extract


ApplicationsIn vivo formation of HgSe

icpTOF results

• Particle size range from liver

extract was 40-100 nm

• Mean Hg:Se was 0.7

• Hg:Se increases with HgSe particle

size

• Fe and Cd are present in single

particles at a significant fraction

Collaboration with Z.Gajdosechova, E. Krupp, J. Feldmann, TESLA, University of Aberdeen


AerosolsSingle particle analysis in air

Background

• Multi-element analysis of airborne

particles is done in bulk and very

time-consuming

• Real time particle detection*

• Faster

• Lower detection limits

• Possible with gas exchange device

(GED)

*Y. Suzuki et al., Spectrochimia Acta B, 2012, 76, 133-139

[3] K. Nishiguchi et al., JAAS, 2008, 23, 1125–1129

to ICP


AerosolsAnalysis of car exhaust

icpTOF results

• Pt- and Ir-bearing particles from

catalytic converter and ignition

spark plug

• Element mass and particle

concentration can be quantified in

the same way as in liquids

Collaboration with K. Nishiguchi, J-Science Lab, Japan

2017.08.02

Imaging

21

Nanoparticle imaging in tissues

Collaboration with M. Grossgarten, U.Karst, Uni Munster

197Au

48Ti197Au

48Ti+197Au

b

max

min

≥500

0

c / µg·g-1

Signal

intensity

31P23Na

27Al 47Ti 90Zr

a

500 µm

48Ti

Laser ablation imaging with icpTOF

• 0.6 mg of Al-, Ti-, Zr- oxide particles

instilled in the rat lung and incubated

for 3 days

• Tissue was imaged by fluorescence

microscopy and LA-icpTOF

• Macrophages labeled with Au and

fluorescent dye

• Correlation of Au with Ti, Al and Zr

particles are in macrophages

Webinar – Multi-element single particle analysis


Summary

icpTOF features

• Simultaneous detection

• Flexible interference control

• Sensitivity

• Mass accuracy

• Speed

Advantages for single particle analysis

• All isotopes in single particle

• Measurement of challenging particles

• Detection limits of 10-100 nm

• Distinguish analyte from interference

• High S/N, lower detection limits

Summary

• RIKILT

• University of Vienna

• University of Aberdeen

• University Münster

• ETH Zürich

• ESI NewWave

• J-Science Lab

• ACEnano

2017.08.02

Acknowledgements

23

Thanks to


TOFWERK AG

Uttigenstrasse 22

CH-3600 Thun, Switzerland

www.tofwerk.com/icp

+41 33 511 1156

• Dr. Martin Tanner – Product Manager icpTOF

[email protected]

• Dr. Olga Borovinskaya – Application Specialist

[email protected]

• Dr. Yannick Bussweiler – Application Specialist

[email protected]

2017.08.02

Contacts

24

Contact us


http://www.tofwerk.com/icp

mailto:[email protected]



multi-element single particle analysis by icptof€¦ · 19 2017.08.02 webinar –multi-element...

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