of MALDI Process by Superconducting Ion Detectors Super-I RIIF, AIST - - PDF document

RIIF, AIST Super-I

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• M. Ohkubo, Y. Shigeri, T. Kinumi, N. Saito, M. Ukibe,Y. E. Chen, A.

Kushino, A. Kurokawa, and S. Ichimura

Fragmentation Analysis

• f MALDI Process by Superconducting Ion Detectors

RIIF, AIST Super-I

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nucleus

15 m

Golgi complex Mitochondria

Dark matter in our body Junk DNA Repeated sequence Epigenetic factor …

Post-genome research Which protein, Where, When, How much

Ribosomes

RIIF, AIST Super-I

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Time-of-flight mass spectrometer

Detection efficiency Mass of molecule

100%

？

~3% for BSA 66.4 kDa

MCP Time of flight (m/z) Ion intensity

MALDI HV N2 laser Mass spectrum

STJ, in principle

RIIF, AIST Super-I

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!"#$%&$'()( 1 MDa

monomer

RIIF, AIST Super-I

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Evidence of 100% detection efficiency

1 2 3 4 5

RIIF, AIST Super-I

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LTD in TOF-MS

• STJ, NIS, TES have been applied to MS.

(PSI, NIST, LLNL, Comet, …)

• MS community may have impression,

very small, slow response, very low temperature, not suitable for top down proteomics. (Intact ion detection is not enough.)

RIIF, AIST Super-I

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• * ns time resolution
• 100 pixel array
• Fragmentation analysis (PSD) by

kinetic energy (MS/MS)

• Trajectory analysis after dissociation

for ionic and neutral molecules (MS/MS)

Our target

RIIF, AIST Super-I

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Fragmentation in top down proteomics

• B. Spengler, JSM 32 1019 (1997)

E E=E1+E2 E2 E1

Ion source Detector

RIIF, AIST Super-I

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Fragmentation in MALDI ion source

! "!! #!! $!! ! %! "!! "%! #!! #%! Kinetic energy (512 ch.) !"#$%&'( BSA++ BSA+

&'()*!+,-)*.$%/

Ion count m/z BSA+ 66430 BSA++

! "! #!! #"! $!! $"! %!! ! "! #!! #"! $!! $"! Kinetic energy (512 ch.) !"#$%&'( BSA+ BSA++

&'()*!+,-)*.$"/

Ion count m/z BSA 66430 BSA++

+