Size-related vaporisation and ionisation of laser-induced glass particles in the inductively coupled plasma

Kuhn, Hans-Rudolf; Guillong, Marcel; Günther, Detlef
February 2004
Analytical & Bioanalytical Chemistry;Feb2004, Vol. 378 Issue 4, p1069
Academic Journal
Ongoing discussions about the origin of elemental fractionation occurring during LA-ICP-MS analysis show that this problem is still far from being well understood. It is becoming accepted that all three possible sources (ablation, transport, excitation) contribute to elemental fractionation. However, experimental data about the vaporisation size limit of different particles in the ICP, as produced in laser ablation, have not been available until now. This information should allow one to determine the signal contributing mass within the ICP and would further clarify demands on suitable laser ablation systems and gas atmospheres in terms of their particle size distribution. The results presented here show a vaporisation size limit of laser induced particles, which was found at particle sizes between 90 nm and 150 nm using an Elan 6000 ICP-MS. Due to the fact that the ICP-MS response was used as evaluation parameter, vaporisation and ionisation limits are not distinguishable. The upper limit was determined by successively removing the larger particles from the aerosol, which was created by ablation of a NIST 610 glass standard at a wavelength of 266 nm, using a recently developed particle separation device. Various particle fractions were separated from the aerosol entering the ICP. The decrease in signal intensity is not proportional to the decrease in volume, indicating that particles above 150 nm in diameter are not completely ionised in the ICP. Due to the limited removal range of the particle separation device, which cannot remove particles smaller than 150 nm, single hole ablations were used to determine the lower vaporisation limit. This is based on measurements showing that larger particles occur dominantly during the first 100 laser pulses only. After this period, the ratio of ICP-MS counts and total particle volume was found to be constant while most of the particles are smaller than 90 nm, indicating complete vaporisation and ionisation of these particles. To describe the influence of different plasma forward powers on the vaporisation limit, the range 1000–1600 W was studied. Results indicate that optimum vaporisation and ionisation occurs at 1300 W. However, an increase of the particle ionisation limit towards larger particles was not observed within the accuracy of this study using the full range of parameters available for optimisation on commonly used ICP-MS instruments.


Related Articles

  • Synthesis of mixed metallic nanoparticles by spark discharge. Tabrizi, N.; Xu, Q.; van der Pers, N.; Lafont, U.; Schmidt-Ott, A. // Journal of Nanoparticle Research;Jul2009, Vol. 11 Issue 5, p1209 

    Abstract  Short spark discharges (2 μs) were successfully applied to generate mixed particles a few nanometres in diameter by fast quenching. Alloyed Cr–Co electrodes were applied to demonstrate this. Further it was shown that if the anode and the cathode are different...

  • Development of an accurate, sensitive, and robust isotope dilution laser ablation ICP-MS method for simultaneous multi-element analysis (chlorine, sulfur, and heavy metals) in coal samples. Boulyga, Sergei F.; Heilmann, Jens; Prohaska, Thomas; Heumann, Klaus G. // Analytical & Bioanalytical Chemistry;Oct2007, Vol. 389 Issue 3, p697 

    A method for the direct multi-element determination of Cl, S, Hg, Pb, Cd, U, Br, Cr, Cu, Fe, and Zn in powdered coal samples has been developed by applying inductively coupled plasma isotope dilution mass spectrometry (ICP-IDMS) with laser-assisted introduction into the plasma. A sector-field...

  • Inductively coupled plasma mass spectrometry: recent trends and developments. Engelhard, Carsten // Analytical & Bioanalytical Chemistry;Jan2011, Vol. 399 Issue 1, p213 

    This year inductively coupled plasma mass spectrometry (ICP-MS) moves into the fourth decade of development. In this article, some recent trends and developments in ICP-MS are reviewed, with special focus on instrumental development and emerging applications. Some key trends include a novel mass...

  • Online electrothermal heating of laser-generated aerosols: effects on aerosol particle size and signal intensities in ICPMS. Brogioli, Robert; Hattendorf, Bodo; Koch, Joachim; Wiltsche, Helmar; Flamigni, Luca; Günther, Detlef // Analytical & Bioanalytical Chemistry;Mar2011, Vol. 399 Issue 6, p2201 

    To achieve separation of isobaric interferences and minimization of matrix related interferences for laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS) electrothermal heating of laser generated aerosols was investigated by analyzing a range of solid samples: NIST SRM 610, MBH...

  • Self-consistent global model with multi-step ionizations in inductively coupled plasmas. Min-Hyong Lee; Chin-Wook Chung // Physics of Plasmas;Jul2005, Vol. 12 Issue 7, p073501 

    Modified particle and power balance equations including multi-step ionizations are derived and solved in a self-consistent manner. According to the modified balance equations, the electron temperature (Te) decreases with the electron density (ne) to balance between the generation and the loss of...

  • On the multistep ionizations in an argon inductively coupled plasma. Min-Hyong Lee; Sung-Ho Jang; Chin-Wook Chung // Physics of Plasmas;May2006, Vol. 13 Issue 5, p052507 

    The effect of the multistep ionizations on the plasma parameters in the inductively coupled plasma (ICP) has been investigated by experiments and theory. To obtain electron density and electron temperature precisely at various powers and pressures in the ICP, the electron energy distribution...

  • On the hysteresis in E to H and H to E transitions and the multistep ionization in inductively coupled plasma. Lee, Min-Hyong; Lee, Kyeong Hyo; Hyun, Dong-Seok; Chung, Chin-Wook // Applied Physics Letters;5/7/2007, Vol. 90 Issue 19, p191502 

    Plasma densities, E to H and H to E transition coil currents, and electron energy distribution functions (EEDFs) are measured at various argon pressures in an inductively coupled plasma. The measured plasma density versus coil current shows that the hysteresis during the E-H transition is...

  • Physical limitations in ferromagnetic inductively coupled plasma sources. Bliokh, Yury P.; Felsteiner, J.; Slutsker, Ya. Z. // Journal of Applied Physics;Feb2013, Vol. 113 Issue 8, p083302 

    The ferromagnetic inductively coupled plasma (FICP) source, which is a version of the common inductively coupled plasma sources, has a number of well known advantages such as high efficiency, high level of ionization, low minimal gas pressure, very low required driver frequency, and even a...

  • Battery-powered pulsed high density inductively coupled plasma source for pre-ionization in laboratory astrophysics experiments. Chaplin, Vernon H.; Bellan, Paul M. // Review of Scientific Instruments;Jul2015, Vol. 86 Issue 7, p1 

    An electrically floating radiofrequency (RF) pre-ionization plasma source has been developed to enable neutral gas breakdown at lower pressures and to access new experimental regimes in the Caltech laboratory astrophysics experiments. The source uses a customized 13.56 MHz class D RF power...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics