Inductively Coupled Plasma - Mass Spectrometry ICP - MS · ความสัมพันธ์ระหว่างปริมาณของเขม่าปืนบนมอ
Properties and Applications of an RF-only Hexapole Collision Cell in ICP Mass Spectrometry
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Properties and Applications of an RF-only Hexapole Collision Cell in ICP Mass Spectrometry J. Speakman, P.J. Turner, R.C.Haines, T.O.Merren, A.N. Eaton, J. Letcher
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Properties and Applications of an RF-only Hexapole Collision Cell in ICP Mass Spectrometry. J. Speakman, P.J. Turner, R.C.Haines, T.O.Merren, A.N. Eaton, J. Letcher. +. The Problem: Argide Interferences. 100. %. 0. 50. 60. Collision cell’s are used on Organic instruments - PowerPoint PPT Presentation
Transcript of Properties and Applications of an RF-only Hexapole Collision Cell in ICP Mass Spectrometry
Properties and Applications of an RF-only Hexapole Collision Cell in ICP Mass Spectrometry
J. Speakman, P.J. Turner, R.C.Haines, T.O.Merren,
A.N. Eaton, J. Letcher
The Problem: Argide Interferences
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Collision cell’s are used on Organic instruments
for MS-MS
Collision cell’s are used on Organic instruments
for MS-MS
Purpose is tofragment &‘thermalise’ ions
Purpose is tofragment &‘thermalise’ ions
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Conventional ICP-MS blank spectrum
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ICP-HEX-MS blank spectrum
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ICP-HEX-MS 10ppb Fe & Co
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ICP-HEX-MS blank spectrumICP-HEX-MS 10ppb Fe & Co
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Conventional ICP-MS blank spectrumICP-HEX-MS blank spectrum
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Conventional ICP-M S blank spectrumICP-H EX-MS blank spectrumICP-H EX-MS 10ppb Fe & Co
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Conventional ICP-M S blank spectrumICP-H EX-MS blank spectrumICP-H EX-MS 10ppb Fe & Co
Ion Energy distribution: no He in Cell
~30V~30V
Ion Energy distribution: He added
~2V~2V
Multiscans of U, Sr & Mg
Results obtained* for JMC475 Hafnium
*Normalised to 179/177=.7325
Intensity for 1ppm 180Hf= 3Volts therefore total Hf 10volts/ppm
Measurement 179/177 ppm 1se 176/177(n) ppm 1se 178/177(n) ppm 1se mins
1 0.748263 17 0.282208 12 1.466992 4 402 0.747898 24 0.282187 18 1.467058 7 203 0.748067 23 0.282162 18 1.467074 8 204 0.747876 23 0.282155 19 1.467114 7 205 0.748184 14 0.282196 11 1.467061 8 206 0.748087 19 0.28221 15 1.467052 8 20
Mean 0.748062 0.282186 1.4670581SD 0.000153 2.34x10-5 3.95x10-5
TIMS 0.7325 0.282195
>109 cps/ppm>109 cps/ppm
Ion Yields
Uranium 1.3 x109 cps/ppmLead 4.2 x109 cps/ppmHafnium 1.9 x109 cps/ppmNeodymium 2.5 x109 cps/ppmStrontium 2 x109 cps/ppm
Uranium 1.3 x109 cps/ppmLead 4.2 x109 cps/ppmHafnium 1.9 x109 cps/ppmNeodymium 2.5 x109 cps/ppmStrontium 2 x109 cps/ppm
99Tc at 1ppb99Tc at 1ppb
Faradaybackground
Faradaybackground
Benefits of Multicollector ICP-MS
Extends the range of elements for which precise isotope ratios can be determinede.g. Ca/Sr, Hf/Lu
Easy to add normalising spikesDirect sampling with laser ablation
e.g. individual Zircons
Benefits of Single-focusing Multicollector ICP-HEX-MS
High transmission: Extreme sensitivity >109 cps/ppm
Faster analysisReliable analyses produced from smaller
samplesSingle shot laser ablation
Extends the range of elements even furtherCa, Fe, Se
Conclusion
Elimination of Ar based interferences-Reduces detection limits on previously difficult elements
such as K, Ca, Fe, As & Se
Reduces ion energy spread-Increases resolution & sensitivity
-Enables precise isotope ratios to be measured on a single focussing multicollector ICP-MS
