A new mass spectrometer based on charge detection has been developed. It enables the determination of mass distribution of various macromolecules and nanoparticles. By using an ion trap coupled to a CO2 laser, photoinduced dissociation of such macroions can be studied at the single ion level giving uniquely access to intrinsic features such as fragmentation patterns and unimolecular dissociation activation energy

Antoine, R.

Doussineau, T.

Dugourd, P.

SocioEconomic Challenges Journal (Sumy State University)

PROCEEDINGS OF THE INTERNATIONAL CONFERENCE  
NANOMATERIALS: APPLICATIONS AND PROPERTIES 
Vol. 3 No 2, 02NNPT06(3pp) (2014) 
 
 
2304-1862/2014/3(2)02NNPT06(3) 02NNPT06-1  2014 Sumy State University 
When Mass Spectrometry Meets Nanoparticles.  
Weighing, Manipulating and Fragmenting Single Nanoparticles in the Gas Phase 
 
T. Doussineau, P. Dugourd, R. Antoine 
 
Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS,  
Université de Lyon 69622 Villeurbanne cedex, France 
 
(Received 10 July 2014; published online 29 August 2014) 
 
A new mass spectrometer based on charge detection has been developed. It enables the determination 
of mass distribution of various macromolecules and nanoparticles. By using an ion trap coupled to a CO2 
laser, photoinduced dissociation of such macroions can be studied at the single ion level giving uniquely ac-
cess to intrinsic features such as fragmentation patterns and unimolecular dissociation activation energy. 
 
Keywords: Mass-spectrometry, Nanoparticles, Biomolecules, Fragmentation. 
 
 PACS numbers: 07.75. + h, 82.35.Np, 65.80. + n, 
87.15.mk 
 
 
1. INTRODUCTION 
 
Mass is a critical feature of compounds related to 
their quantity of matter, their inertia, as well as their 
energies. To measure mass one can use a scale or a 
balance, both of which rely on Earth's gravity. The 
balances we use today in our laboratories can even 
detect masses down to 10-7 g but this measurement 
method becomes inadequate below this limit. Although 
this low mass can be measured by mass spectrometers 
that use electric or magnetic field to separate ionized 
compounds according to their mass-to-charge (m/z) 
ratio. However conventional mass spectrometry (MS) 
has limitations for weighing macroions with masses 
higher than one megadalton (1 MDa or 10-18 g) [1]. 
Above this limit, mass-to-charge (m/z) spectra become 
unsolvable due to the fact that high mass ions may 
carry an unresolvable distribution of charges. Moreover 
large ions may not all have exactly the same mass due 
to sample heterogeneity (i.e. polydispersity), residual 
adsorbates such as water molecules and counter ions. 
One solution to overcome these limitations is to 
measure both the mass-to-charge ratio (m/z) and the 
charge (z) for each ion. This single ion mass spectrome-
try enables one to construct a histogram of mass yield-
ing the true mass distribution. A convenient way to 
measure the charge of individual ions is to use image 
charge detection.  A multi-charged ion in the proximity 
of a conductive surface impresses on it an equal and 
opposite image charge. This approach was pioneered by 
Shelton in 1960 for characterizing multiply charged 
microparticles [2]. Based on this concept of image cur-
rent detection, charge-detection mass spectrometry 
(CD-MS) coupled to electrospray ionization (ESI) was 
introduced by Benner and coworkers in 1995 for weigh-
ing macroions with masses higher than one megadal-
ton.3 The passage of a multicharged ion through the 
detection tube induces on it a voltage proportional to 
the charge of the ion and inversely proportional to the 
capacity of the system. The duration of this induced 
signal is equal to the time-of-flight (ToF) of the ion 
through the detector. By measuring simultaneously 
velocity and charge of individual ions, and together 
with measuring the acceleration voltage, one can com-
pute the mass of the ion. This allows one to extend the 
limit of conventional mass spectrometry towards high 
mass compounds, as demonstrated for large DNA 
strands [4, 5], viruses [6, 7], liquid droplets [8] and 
macropolymers [9, 10]. 
While a single stage MS experiment determines the 
mass of an analyte, tandem MS (MS/MS) can provide 
information on its structure. Typical MS/MS experi-
ments involve mass selection of the ion of interest in 
the first MS stage, excitation of the ion followed by its 
dissociation and mass analysis of the resulting frag-
ment ions in the second MS stage. MS/MS has been 
used to elucidate the structure of a variety of small to 
medium-sized molecular ions. Due to the difficulty of 
detecting large size ions, MS/MS on compounds of 
megadalton (MDa) molecular weight is almost an un-
explored field yet. We recently implemented tandem 
mass spectrometry for experiments on single elec-
trosprayed ions from compounds of megadalton molecu-
lar weight, using two charge detection devices (CDDs) 
[11] This paper briefly describes the mass spectrometry 
developments for mass and structural determination of 
nanoparticles. 
 
2. WEIGHING, MANIPULATING AND FRAG-
MENTING SINGLE NANOPARTICLES IN THE 
GAS PHASE 
 
2.1 Instrumentation 
 
We developed a custom-built tandem charge 
detection mass spectrometer (CD-MS/MS) composed by 
an electrospray ionization source (ESI) coupled to two 
CDDs. The ESI source generates highly charged 
macroions which are guided by an ionic train to the mass 
spectrometer (Figure 1). Ions are guided up to a vacuum 
stage chamber (~10-6 mbar) which contains two identical 
CDDs used as a tandem mass spectrometer. Each CDD 
consists of a conductive tube collinear to the ion beam 
and connected to a field-effect transistor (JFET). The 
picked up signal given by the passage of a single ion 
through the detection tube is amplified by a low-noise 
charge-sensitive preamplifier and then shaped and 
differentiated by a home-built amplifier.  
 T. DOUSSINEAU, P. DUGOURD, R. ANTOINE PROC. NAP 3, 02NNPT06 (2014) 
 
 
02NNPT06-2 
 
 
Fig. 1 – Experimental setup for tandem charge detection mass 
spectrometry (CD-MS/MS). (inset) Photo of the gated 
electrostatic ion trap composed by a charge detection device 
surrounded by electrodes. 
 
The signal is recorded with a waveform digitizer 
card. The data are transferred to a desk-top computer-
where they are analyzed with a custom-written user 
program. Calibration in charge was performed using a 
test capacitor that allowed a known amount of charge 
to be pulsed onto the pick-up tube.  
The first CDD is used in a single-pass mode and al-
lows ions to be selected and measured in the second 
CDD. In the single-pass mode, the picked up signal 
from each single ion composing the sample generated 
in the electrospray source is measured. Electrical noise 
limits the charge measurements in CD-MS. A root 
mean square (rms) noise of ± 250 e is usually obtained, 
and a precision in charge measurement of about ~15%. 
In addition to the reduction of noise in the charge 
measurement circuit, an approach that improves the 
limit of the charge measurement is to re-measure the 
charge on individual ions by using an array of charge 
detection devices or electrostatic ion trap. However, the 
moderate precision in charge measurement is largely 
compensated by the high count rate that can be 
achieved (1000 ions/s). From the analysis of each wave-
form one can thus rapidly determine, knowing the 
acceleration voltage, the mass of each single ion that 
has travelled through the tube. 
 The second CDD is used as a gated electrostatic ion 
trap, as proposed by Benner [12]. The conductive tube 
surrounded by two ion mirrors (inset Figure 1) and 
preceded by an ion gate. Ions are selected both in m/z 
and z by synchronisation of the first CDD and the ion 
gate. A selected ion can be trapped between the 2 ion 
mirrors if correct voltages are applied on the electrodes 
of the ion mirror. During the trapping time a continu-
ous wave CO2 laser can be used in a synchronized 
manner to irradiate the trapped ion through a ZnSe 
window for ~50 ms. 
 
2.2 Molecular weight determination of  
nanoparticles  
 
In the single-pass mode each single ion composing 
the sample generated in the electrospray source can be 
detected and measured. On this basis mass distributions 
of synthetic NIST standard polystyrene particles (100 
nm diameter) were accurately determined. Obtained 
averaged molar masses can be con verted in diameter of 
spherical particles and are in good agreement with those 
 
Fig. 2 – a) mass-charge map obtained in CD-MS of 100 nm 
diameter NIST standard polystyrene bead.  b) TEM image of 
Au@citrate nanoparticles (J. Kimling, M. Maier, B. Okenve, V. 
Kotaidis, H. Ballot and A. Plech, et al., J. Phys. Chem. B 110, 
15700 (2006)) ; average diameter ca 40 nm) and corresponding 
molar mass distribution obtained in CD-MS. 
 
given by the supplier. The versatility of the electrospray 
source to “make fly elephants” [13] allowed us to study a 
large panel of nano-objets such as gold and silica nano-
particles. As an example, Figure 2b shows mass distri-
butions obtained for a colloidal suspension of gold nano-
particles. An important aspect of charge detection MS is 
that charge of NPs can be measured simultaneously 
with their mass. This allowed to us to explore the charg-
ing capacity of NPs in the gas phase14 and the correla-
tion between the charge of particles in solution and in 
the gas phase.15 
 
2.3 Trapping and infrared multi-photon  
dissociation of single megadalton ions 
 
A single macroion selected in mass and charge can 
be trapped in the second CDD during several tens of 
milliseconds, which corresponds to several hundreds of 
oscillations. This generates an electric wavelet on the 
detector. The first benefit is that we can re-measure 
charge and time-of-flight as many times as the ion 
oscillates in the trap improving the z and m/z precision 
of CD-MS measurements. Fig. 3a shows the experi-
mental raw time domain signal for a trapped ion creat-
ed by a single highly charged electrospray ion of PEO 
(mass of 20 MDa and 1550 charges) travelling back and 
forth through the ion trap. The Fourier transform of 
this signal (inset in Fig. 3a) shows a peak at 13.8  kHz 
indicating the fundamental  oscillation frequency, 
which corresponds to an m/z of 12900 Da/e. The first 
a)
b)
200 400 600
500
1000
1500
 
 
c
h
a
rg
e
 (
e
)
masse (MDa)
100 nm NIST-standard PS beads
masse
charge
mass
mass
 WHEN MASS SPECTROMETRY MEETS NANOPARTICLES… PROC. NAP 3, 02NNPT06 (2014) 
 
 
02NNPT06-3 
 
 
Fig. 3 – (a). Experimental raw time domain signal for a 
trapped PEO ion (mass of 20 MDa and 1550 charges). The 
inset shows the Fourier transform of the raw signal with a 
fundamental oscillation frequency of 13.8 kHz and a first 
harmonic also seen at 27.6 kHz. Experimental raw time 
domain signal for a single trapped PEO ion under continuous 
irradiation of the CO2 laser (14.6 W/cm2). The onset and 
disappearance times (to and td) are shown as arrows. 
 
harmonic can be seen at 27.6 kHz. This single ion was 
trapped for ∼ 52 ms, during which it cycled ∼750 times 
through the detector tube. The shape and amplitude of 
the raw signal are roughly the same, which means that 
no significant charge loss is observed during the trap-
ping time. During their storage time, single ions can be 
irradiated by the CO2 laser. The CO2 laser provides 
low-energy IR photons. Macroions can be efficiently 
heated by multiple absorption of IR photons (infrared 
multi-photon dissociation (IRMPD) experiments) [16, 
17]. As the laser is switched on during the ion trapping 
time, drastic changes are observed both in the trapping 
duration and the shape of the oscillations. As shown in 
Figure 3b, for selected raw time domain signals for a 
single trapped ion, under continuous irradiation by the 
CO2 laser (14.6 W/cm2). This trace corresponds to “stair-
case” types of raw time domain signals. The ion has a trap-
ping time that does not exceed 20 ms. The precursor 
ion suddenly loses a large amount of charge (~35% of 
initial charge) after ~8.5 ms, then the amplitude of the 
charge remains almost constant for ~8 ms before the 
ion can no longer be detected. Another type of raw time 
domain signal referred to as “funnel” is also often ob-
served. During the last stages, the total charge gradu-
ally decreases before the ion is lost or cannot be detect-
ed [18, 19] The activation energy associated with the 
dissociation of megadalton-size ions was estimated, in 
the frame of an Arrhenius-like model, by analyzing a 
large set of individual ions in order to construct a fre-
quency histogram of the dissociation rates for a collec-
tion of ions [19]. 
 
3. CONCLUSION  
 
CD-MS and CD-MS/MS working in the single-pass 
and multi-pass modes, respectively, provide unique data 
on compounds of molar mass ranging from megadalton 
to gigadalton. In particular the determination of molar 
mass distribution of various nano-objects has been 
demonstrated and this key characterization may be 
extended to the so-called „nanoworld‟. The implementa-
tion of an electrostatic ion trap significantly improves 
the precision of mass measurements and allows one to 
study kinetics of dissociation of large macroions. In par-
ticular, IRMPD was found to be a promising tool for 
studying unimolecular dissociation of large macroions at 
the single ion level. 
 
AKNOWLEDGEMENTS 
 
We are grateful to the ANR for financial support of 
this work (ANR-08-BLAN-0110-01 and ANR-11-PDOC-
032-01). 
 
 
REFERENCES 
 
1. E. van Duijn, D.A. Simmons, R.H.H. van den Heuvel, 
P.J. Bakkes, H. van Heerikhuizen, R.M.A. Heeren, 
C.V. Robinson, S.M. van der Vies, and A.J.R. Heck, J. Am. 
Chem. Soc. 128, 4694 (2006). 
2. H. Shelton, C.D. Hendricks, Jr., and R.F. Wuerker, J. Appl. 
Phys. 31, 1243 (1960). 
3. S.D. Fuerstenau, and W.H. Benner, Rapid Commun. Mass 
Spectrom. 9, 1528 (1995). 
4. J.C. Schultz, C.A. Hack, and W.H. Benner, J. Am. Soc. Mass 
Spectrom. 9, 305 (1998). 
5. J.C. Schultz, C.A. Hack, and W.H. Benner, Rapid Commun. 
Mass Spectrom. 13, 15 (1999). 
6. W.-P. Peng, Y.-C. Yang, M.-W. Kang, Y.-K. Tzeng, Z. Nie, 
H.-C. Chang, W. Chang, and C.-H. Chen, Angewandte 
Chemie International Edition 45, 1423 (2006). 
7. S.D. Fuerstenau, W.H. Benner, J.J. Thomas, C. Brugidou, B. 
Bothner, and G. Siuzdak, Angew. Chem.-Int. 40, 542 (2001). 
8. J.T. Maze, T.C. Jones, and M.F. Jarrold, J. Phys. Chem. A 
110, 12607 (2006). 
9. T. Doussineau, C.Y. Bao, R. Antoine, P. Dugourd,  
W. Zhang, F. D'Agosto, and B. Charleux, ACS Macro Lett. 1, 
414 (2012). 
10. T. Doussineau, M. Kerleroux, X. Dagany, C. Clavier,  
M. Barbaire, J. Maurelli, R. Antoine, and P. Dugourd,  
Rapid Commun. Mass Spectrom. 25, 617 (2011). 
11. T. Doussineau, C.Y. Bao, C. Clavier, X. Dagany, M. Kerle-
roux, R. Antoine and P. Dugourd, Rev. Sci. Instrum. 82, 
084104 (2011). 
12. W.H. Benner, Anal. Chem. 69, 4162 (1997). 
13. J.B. Fenn, M. Mann, C.K. Meng, S.F. Wong and  
C.M. Whitehouse, Science 246, 64 (1989). 
14. T. Doussineau, M. Santacreu, R. Antoine, P. Dugourd,  
W. Zhang, I. Chaduc, M. Lansalot, F. D'Agosto and  
B. Charleux, Chem. Phys. Chem. 14, 603 (2013). 
15. N. Ouadah, T. Doussineau, T. Hamada, P. Dugourd,  
C. Bordes and R. Antoine, Langmuir 29, 14074 (2013). 
16. R.C. Dunbar, Mass Spectr. Rev. 23, 127 (2004). 
17. K. Paech, R.A. Jockusch, and E.R. Williams, J. Phys. 
Chem. A 106, 9761 (2002). 
18. R. Antoine, T. Doussineau, P. Dugourd and F. Calvo, Phys. 
Rev. A 87, 013435 (2013). 
19. T. Doussineau, R. Antoine, M. Santacreu, and P. Dugourd, 
J. Phys. Chem. Lett. 3, 2141 (2012). 
  
8 12 16 20 24 28
0
2
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6
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A
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p
lit
u
d
e
0.01 0.02 0.03 0.04 0.05
-2000
-1000
0
1000
2000
c
h
a
rg
e
 z
e
trapping time (s)
(b)
0.01 0.02 0.03 0.04 0.05
-2000
-1000
0
1000
2000
C
h
a
rg
e
 (
z
e
)
Trapping time (s)
0.005 0.010 0.015 0.020
400
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English

When Mass Spectrometry Meets Nanoparticles. Weighing, Manipulating and Fragmenting Single Nanoparticles in The Gas Phase

Electronic Sumy State University Institutional Repository

PROCEEDINGS OF THE INTERNATIONAL CONFERENCE  NANOMATERIALS: APPLICATIONS AND PROPERTIES Vol. 3 No 2, 02NNPT06(3pp) (2014)   2304-1862/2014/3(2)02NNPT06(3) 02NNPT06-1  2014 Sumy State University When Mass Spectrometry Meets Nanoparticles.  Weighing, Manipulating and Fragmenting Single Nanoparticles in the Gas Phase  T. Doussineau, P. Dugourd, R. Antoine  Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS,  Université de Lyon 69622 Villeurbanne cedex, France  (Received 10 July 2014; published online 29 August 2014)  A new mass spectrometer based on charge detection has been developed. It enables the determination of mass distribution of various macromolecules and nanoparticles. By using an ion trap coupled to a CO2 laser, photoinduced dissociation of such macroions can be studied at the single ion level giving uniquely ac-cess to intrinsic features such as fragmentation patterns and unimolecular dissociation activation energy.  Keywords: Mass-spectrometry, Nanoparticles, Biomolecules, Fragmentation.   PACS numbers: 07.75. + h, 82.35.Np, 65.80. + n, 87.15.mk   1. INTRODUCTION  Mass is a critical feature of compounds related to their quantity of matter, their inertia, as well as their energies. To measure mass one can use a scale or a balance, both of which rely on Earth's gravity. The balances we use today in our laboratories can even detect masses down to 10-7 g but this measurement method becomes inadequate below this limit. Although this low mass can be measured by mass spectrometers that use electric or magnetic field to separate ionized compounds according to their mass-to-charge (m/z) ratio. However conventional mass spectrometry (MS) has limitations for weighing macroions with masses higher than one megadalton (1 MDa or 10-18 g) [1]. Above this limit, mass-to-charge (m/z) spectra become unsolvable due to the fact that high mass ions may carry an unresolvable distribution of charges. Moreover large ions may not all have exactly the same mass due to sample heterogeneity (i.e. polydispersity), residual adsorbates such as water molecules and counter ions. One solution to overcome these limitations is to measure both the mass-to-charge ratio (m/z) and the charge (z) for each ion. This single ion mass spectrome-try enables one to construct a histogram of mass yield-ing the true mass distribution. A convenient way to measure the charge of individual ions is to use image charge detection.  A multi-charged ion in the proximity of a conductive surface impresses on it an equal and opposite image charge. This approach was pioneered by Shelton in 1960 for characterizing multiply charged microparticles [2]. Based on this concept of image cur-rent detection, charge-detection mass spectrometry (CD-MS) coupled to electrospray ionization (ESI) was introduced by Benner and coworkers in 1995 for weigh-ing macroions with masses higher than one megadal-ton.3 The passage of a multicharged ion through the detection tube induces on it a voltage proportional to the charge of the ion and inversely proportional to the capacity of the system. The duration of this induced signal is equal to the time-of-flight (ToF) of the ion through the detector. By measuring simultaneously velocity and charge of individual ions, and together with measuring the acceleration voltage, one can com-pute the mass of the ion. This allows one to extend the limit of conventional mass spectrometry towards high mass compounds, as demonstrated for large DNA strands [4, 5], viruses [6, 7], liquid droplets [8] and macropolymers [9, 10]. While a single stage MS experiment determines the mass of an analyte, tandem MS (MS/MS) can provide information on its structure. Typical MS/MS experi-ments involve mass selection of the ion of interest in the first MS stage, excitation of the ion followed by its dissociation and mass analysis of the resulting frag-ment ions in the second MS stage. MS/MS has been used to elucidate the structure of a variety of small to medium-sized molecular ions. Due to the difficulty of detecting large size ions, MS/MS on compounds of megadalton (MDa) molecular weight is almost an un-explored field yet. We recently implemented tandem mass spectrometry for experiments on single elec-trosprayed ions from compounds of megadalton molecu-lar weight, using two charge detection devices (CDDs) [11] This paper briefly describes the mass spectrometry developments for mass and structural determination of nanoparticles.  2. WEIGHING, MANIPULATING AND FRAG-MENTING SINGLE NANOPARTICLES IN THE GAS PHASE  2.1 Instrumentation  We developed a custom-built tandem charge detection mass spectrometer (CD-MS/MS) composed by an electrospray ionization source (ESI) coupled to two CDDs. The ESI source generates highly charged macroions which are guided by an ionic train to the mass spectrometer (Figure 1). Ions are guided up to a vacuum stage chamber (~10-6 mbar) which contains two identical CDDs used as a tandem mass spectrometer. Each CDD consists of a conductive tube collinear to the ion beam and connected to a field-effect transistor (JFET). The picked up signal given by the passage of a single ion through the detection tube is amplified by a low-noise charge-sensitive preamplifier and then shaped and differentiated by a home-built amplifier.   T. DOUSSINEAU, P. DUGOURD, R. ANTOINE PROC. NAP 3, 02NNPT06 (2014)   02NNPT06-2   Fig. 1 – Experimental setup for tandem charge detection mass spectrometry (CD-MS/MS). (inset) Photo of the gated electrostatic ion trap composed by a charge detection device surrounded by electrodes.  The signal is recorded with a waveform digitizer card. The data are transferred to a desk-top computer-where they are analyzed with a custom-written user program. Calibration in charge was performed using a test capacitor that allowed a known amount of charge to be pulsed onto the pick-up tube.  The first CDD is used in a single-pass mode and al-lows ions to be selected and measured in the second CDD. In the single-pass mode, the picked up signal from each single ion composing the sample generated in the electrospray source is measured. Electrical noise limits the charge measurements in CD-MS. A root mean square (rms) noise of ± 250 e is usually obtained, and a precision in charge measurement of about ~15%. In addition to the reduction of noise in the charge measurement circuit, an approach that improves the limit of the charge measurement is to re-measure the charge on individual ions by using an array of charge detection devices or electrostatic ion trap. However, the moderate precision in charge measurement is largely compensated by the high count rate that can be achieved (1000 ions/s). From the analysis of each wave-form one can thus rapidly determine, knowing the acceleration voltage, the mass of each single ion that has travelled through the tube.  The second CDD is used as a gated electrostatic ion trap, as proposed by Benner [12]. The conductive tube surrounded by two ion mirrors (inset Figure 1) and preceded by an ion gate. Ions are selected both in m/z and z by synchronisation of the first CDD and the ion gate. A selected ion can be trapped between the 2 ion mirrors if correct voltages are applied on the electrodes of the ion mirror. During the trapping time a continu-ous wave CO2 laser can be used in a synchronized manner to irradiate the trapped ion through a ZnSe window for ~50 ms.  2.2 Molecular weight determination of  nanoparticles   In the single-pass mode each single ion composing the sample generated in the electrospray source can be detected and measured. On this basis mass distributions of synthetic NIST standard polystyrene particles (100 nm diameter) were accurately determined. Obtained averaged molar masses can be con verted in diameter of spherical particles and are in good agreement with those  Fig. 2 – a) mass-charge map obtained in CD-MS of 100 nm diameter NIST standard polystyrene bead.  b) TEM image of Au@citrate nanoparticles (J. Kimling, M. Maier, B. Okenve, V. Kotaidis, H. Ballot and A. Plech, et al., J. Phys. Chem. B 110, 15700 (2006)) ; average diameter ca 40 nm) and corresponding molar mass distribution obtained in CD-MS.  given by the supplier. The versatility of the electrospray source to “make fly elephants” [13] allowed us to study a large panel of nano-objets such as gold and silica nano-particles. As an example, Figure 2b shows mass distri-butions obtained for a colloidal suspension of gold nano-particles. An important aspect of charge detection MS is that charge of NPs can be measured simultaneously with their mass. This allowed to us to explore the charg-ing capacity of NPs in the gas phase14 and the correla-tion between the charge of particles in solution and in the gas phase.15  2.3 Trapping and infrared multi-photon  dissociation of single megadalton ions  A single macroion selected in mass and charge can be trapped in the second CDD during several tens of milliseconds, which corresponds to several hundreds of oscillations. This generates an electric wavelet on the detector. The first benefit is that we can re-measure charge and time-of-flight as many times as the ion oscillates in the trap improving the z and m/z precision of CD-MS measurements. Fig. 3a shows the experi-mental raw time domain signal for a trapped ion creat-ed by a single highly charged electrospray ion of PEO (mass of 20 MDa and 1550 charges) travelling back and forth through the ion trap. The Fourier transform of this signal (inset in Fig. 3a) shows a peak at 13.8  kHz indicating the fundamental  oscillation frequency, which corresponds to an m/z of 12900 Da/e. The first a)b)200 400 60050010001500  charge (e)masse (MDa)100 nm NIST-standard PS beadsmassechargemassmass WHEN MASS SPECTROMETRY MEETS NANOPARTICLES… PROC. NAP 3, 02NNPT06 (2014)   02NNPT06-3   Fig. 3 – (a). Experimental raw time domain signal for a trapped PEO ion (mass of 20 MDa and 1550 charges). The inset shows the Fourier transform of the raw signal with a fundamental oscillation frequency of 13.8 kHz and a first harmonic also seen at 27.6 kHz. Experimental raw time domain signal for a single trapped PEO ion under continuous irradiation of the CO2 laser (14.6 W/cm2). The onset and disappearance times (to and td) are shown as arrows.  harmonic can be seen at 27.6 kHz. This single ion was trapped for ∼ 52 ms, during which it cycled ∼750 times through the detector tube. The shape and amplitude of the raw signal are roughly the same, which means that no significant charge loss is observed during the trap-ping time. During their storage time, single ions can be irradiated by the CO2 laser. The CO2 laser provides low-energy IR photons. Macroions can be efficiently heated by multiple absorption of IR photons (infrared multi-photon dissociation (IRMPD) experiments) [16, 17]. As the laser is switched on during the ion trapping time, drastic changes are observed both in the trapping duration and the shape of the oscillations. As shown in Figure 3b, for selected raw time domain signals for a single trapped ion, under continuous irradiation by the CO2 laser (14.6 W/cm2). This trace corresponds to “stair-case” types of raw time domain signals. The ion has a trap-ping time that does not exceed 20 ms. The precursor ion suddenly loses a large amount of charge (~35% of initial charge) after ~8.5 ms, then the amplitude of the charge remains almost constant for ~8 ms before the ion can no longer be detected. Another type of raw time domain signal referred to as “funnel” is also often ob-served. During the last stages, the total charge gradu-ally decreases before the ion is lost or cannot be detect-ed [18, 19] The activation energy associated with the dissociation of megadalton-size ions was estimated, in the frame of an Arrhenius-like model, by analyzing a large set of individual ions in order to construct a fre-quency histogram of the dissociation rates for a collec-tion of ions [19].  3. CONCLUSION   CD-MS and CD-MS/MS working in the single-pass and multi-pass modes, respectively, provide unique data on compounds of molar mass ranging from megadalton to gigadalton. In particular the determination of molar mass distribution of various nano-objects has been demonstrated and this key characterization may be extended to the so-called „nanoworld‟. The implementa-tion of an electrostatic ion trap significantly improves the precision of mass measurements and allows one to study kinetics of dissociation of large macroions. In par-ticular, IRMPD was found to be a promising tool for studying unimolecular dissociation of large macroions at the single ion level.  AKNOWLEDGEMENTS  We are grateful to the ANR for financial support of this work (ANR-08-BLAN-0110-01 and ANR-11-PDOC-032-01).   REFERENCES  1. E. van Duijn, D.A. Simmons, R.H.H. van den Heuvel, P.J. Bakkes, H. van Heerikhuizen, R.M.A. Heeren, C.V. Robinson, S.M. van der Vies, and A.J.R. Heck, J. Am. Chem. Soc. 128, 4694 (2006). 2. H. Shelton, C.D. Hendricks, Jr., and R.F. Wuerker, J. Appl. Phys. 31, 1243 (1960). 3. S.D. Fuerstenau, and W.H. Benner, Rapid Commun. Mass Spectrom. 9, 1528 (1995). 4. J.C. Schultz, C.A. Hack, and W.H. Benner, J. Am. Soc. Mass Spectrom. 9, 305 (1998). 5. J.C. Schultz, C.A. Hack, and W.H. Benner, Rapid Commun. Mass Spectrom. 13, 15 (1999). 6. W.-P. Peng, Y.-C. Yang, M.-W. Kang, Y.-K. Tzeng, Z. Nie, H.-C. Chang, W. Chang, and C.-H. Chen, Angewandte Chemie International Edition 45, 1423 (2006). 7. S.D. Fuerstenau, W.H. Benner, J.J. Thomas, C. Brugidou, B. Bothner, and G. Siuzdak, Angew. Chem.-Int. 40, 542 (2001). 8. J.T. Maze, T.C. Jones, and M.F. Jarrold, J. Phys. Chem. A 110, 12607 (2006). 9. T. Doussineau, C.Y. Bao, R. Antoine, P. Dugourd,  W. Zhang, F. D'Agosto, and B. Charleux, ACS Macro Lett. 1, 414 (2012). 10. T. Doussineau, M. Kerleroux, X. Dagany, C. Clavier,  M. Barbaire, J. Maurelli, R. Antoine, and P. Dugourd,  Rapid Commun. Mass Spectrom. 25, 617 (2011). 11. T. Doussineau, C.Y. Bao, C. Clavier, X. Dagany, M. Kerle-roux, R. Antoine and P. Dugourd, Rev. Sci. Instrum. 82, 084104 (2011). 12. W.H. Benner, Anal. Chem. 69, 4162 (1997). 13. J.B. Fenn, M. Mann, C.K. Meng, S.F. Wong and  C.M. Whitehouse, Science 246, 64 (1989). 14. T. Doussineau, M. Santacreu, R. Antoine, P. Dugourd,  W. Zhang, I. Chaduc, M. Lansalot, F. D'Agosto and  B. Charleux, Chem. Phys. Chem. 14, 603 (2013). 15. N. Ouadah, T. Doussineau, T. Hamada, P. Dugourd,  C. Bordes and R. Antoine, Langmuir 29, 14074 (2013). 16. R.C. Dunbar, Mass Spectr. Rev. 23, 127 (2004). 17. K. Paech, R.A. Jockusch, and E.R. Williams, J. Phys. Chem. A 106, 9761 (2002). 18. R. Antoine, T. Doussineau, P. Dugourd and F. Calvo, Phys. Rev. A 87, 013435 (2013). 19. T. Doussineau, R. Antoine, M. Santacreu, and P. Dugourd, J. Phys. Chem. Lett. 3, 2141 (2012).   8 12 16 20 24 280246Frequency (kHz)Amplitude0.01 0.02 0.03 0.04 0.05-2000-1000010002000charge zetrapping time (s)(b)0.01 0.02 0.03 0.04 0.05-2000-1000010002000Charge (ze)Trapping time (s)0.005 0.010 0.015 0.020400600800100012001400Charge (ze)Trapping time (s)totd(a)

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When Mass Spectrometry Meets Nanoparticles. Weighing, Manipulating and Fragmenting Single Nanoparticles in The Gas Phase

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