Desorption/Ionization on Silicon (DIOS)

Yiming ChenSeptember 19th, 2012

DIOS: Overview

• Analyze proteins and related small molecules without matrix interference

• Yield little or no fragmentation with absence of matrix

• Femtomole level sensitivity, easy to quantificate

DIOS: Overview

Wei, J.; Buriak, J. M.; Siuzdak, G. Nature 1999, 399, 243–246.

DIOS: Overview

• Generation of porous silicon from crystalline silicon by using galvanostatic etching

• Surface is chemically modified

• Analytes are deposited and trapped by porous silicon layer

• Analytes are vaporized and ionized by pulse laser radiation

• Advantages: low background in the low mass range; uniform deposition of aqueous samples; and simplified sample handling

• A p p l i c a t i o n : a n a l y z e s m a l l m o l e c u l e s transformation

DIOS: Overview

DIOS: Application

Thomas, J. J.; Shen, Z.; Crowell, J. E.; Finn, M. G.; Siuzdak, G. Proc. Natl. Acad. Sci. U.S.A. 2001, 98, 4932–4937.

Monitoring inhibition of acetylcholinesterase.

DIOS: Application

Thomas, J. J.; Shen, Z.; Crowell, J. E.; Finn, M. G.; Siuzdak, G. Proc. Natl. Acad. Sci. U.S.A. 2001, 98, 4932–4937.

Monitoring on-plate enzymatic reaction catalyzed by phospholipase.

DIOS: Application

An on-plate tryptic digestion of adenovirus penton protein.

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