PMID- 22305899
OWN - NLM
STAT- MEDLINE
DCOM- 20120521
LR  - 20191210
IS  - 1873-4324 (Electronic)
IS  - 0003-2670 (Linking)
VI  - 718
DP  - 2012 Mar 9
TI  - Parallel detection, quantification, and depth profiling of peptides with 
      dynamic-secondary ion mass spectrometry (D-SIMS) ionized by C60(+)-Ar(+) 
      co-sputtering.
PG  - 64-9
LID - 10.1016/j.aca.2011.12.064 [doi]
AB  - Time-of-flight secondary ion mass spectrometry (ToF-SIMS) using pulsed C(60)(+) 
      primary ions is a promising technique for analyzing biological specimens with 
      high surface sensitivities. With molecular secondary ions of high masses, 
      multiple molecules can be identified simultaneously without prior separation or 
      isotope labeling. Previous reports using the C(60)(+) primary ion have been based 
      on static-SIMS, which makes depth profiling complicated. Therefore, a 
      dynamic-SIMS technique is reported here. Mixed peptides in the cryoprotectant 
      trehalose were used as a model for evaluating the parameters that lead to the 
      parallel detection and quantification of biomaterials. Trehalose was mixed 
      separately with different concentrations of peptides. The peptide secondary ion 
      intensities (normalized with respect to those of trehalose) were directly 
      proportional to their concentration in the matrix (0.01-2.5 mol%). Quantification 
      curves for each peptide were generated by plotting the percentage of peptides in 
      trehalose versus the normalized SIMS intensities. Using these curves, the 
      parallel detection, identification, and quantification of multiple peptides was 
      achieved. Low energy Ar(+) was used to co-sputter and ionize the peptide-doped 
      trehalose sample to suppress the carbon deposition associated with C(60)(+) 
      bombardment, which suppressed the ion intensities during the depth profiling. 
      This co-sputtering technique yielded steadier molecular ion intensities than when 
      using a single C(60)(+) beam. In other words, co-sputtering is suitable for the 
      depth profiling of thick specimens. In addition, the smoother surface generated 
      by co-sputtering yielded greater depth resolution than C(60)(+) sputtering. 
      Furthermore, because C(60)(+) is responsible for generating the molecular ions, 
      the dosage of the auxiliary Ar(+) does not significantly affect the 
      quantification curves.
CI  - Copyright (c) 2012 Elsevier B.V. All rights reserved.
FAU - Chang, Chi-Jen
AU  - Chang CJ
AD  - Department of Materials Science and Engineering, National Taiwan University, 
      Taipei 106, Taiwan.
FAU - Chang, Hsun-Yun
AU  - Chang HY
FAU - You, Yun-Wen
AU  - You YW
FAU - Liao, Hua-Yang
AU  - Liao HY
FAU - Kuo, Yu-Ting
AU  - Kuo YT
FAU - Kao, Wei-Lun
AU  - Kao WL
FAU - Yen, Guo-Ji
AU  - Yen GJ
FAU - Tsai, Meng-Hung
AU  - Tsai MH
FAU - Shyue, Jing-Jong
AU  - Shyue JJ
LA  - eng
PT  - Evaluation Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20120108
PL  - Netherlands
TA  - Anal Chim Acta
JT  - Analytica chimica acta
JID - 0370534
RN  - 0 (Fullerenes)
RN  - 0 (Ions)
RN  - 0 (Peptides)
RN  - 67XQY1V3KH (Argon)
RN  - NP9U26B839 (fullerene C60)
SB  - IM
MH  - Amino Acid Sequence
MH  - Argon/chemistry
MH  - Calibration
MH  - Fullerenes/chemistry
MH  - Ions/chemistry
MH  - Molecular Sequence Data
MH  - Peptides/*chemistry
MH  - Spectrometry, Mass, Secondary Ion/*methods
EDAT- 2012/02/07 06:00
MHDA- 2012/05/23 06:00
CRDT- 2012/02/07 06:00
PHST- 2011/10/14 00:00 [received]
PHST- 2011/12/25 00:00 [revised]
PHST- 2011/12/28 00:00 [accepted]
PHST- 2012/02/07 06:00 [entrez]
PHST- 2012/02/07 06:00 [pubmed]
PHST- 2012/05/23 06:00 [medline]
AID - S0003-2670(12)00005-0 [pii]
AID - 10.1016/j.aca.2011.12.064 [doi]
PST - ppublish
SO  - Anal Chim Acta. 2012 Mar 9;718:64-9. doi: 10.1016/j.aca.2011.12.064. Epub 2012 
      Jan 8.