LIAD-fs scheme for studies of ultrafast laser interactions with gas phase biomolecules.
Phys Chem Chem Phys
; 14(18): 6289-97, 2012 May 14.
Article
en En
| MEDLINE
| ID: mdl-22322861
Laser induced acoustic desorption (LIAD) has been used for the first time to study the parent ion production and fragmentation mechanisms of a biological molecule in an intense femtosecond (fs) laser field. The photoacoustic shock wave generated in the analyte substrate (thin Ta foil) has been simulated using the hydrodynamic HYADES code, and the full LIAD process has been experimentally characterised as a function of the desorption UV-laser pulse parameters. Observed neutral plumes of densities >10(9) cm(-3) which are free from solvent or matrix contamination demonstrate the suitability and potential of the source for studying ultrafast dynamics in the gas phase using fs laser pulses. Results obtained with phenylalanine show that through manipulation of fundamental femtosecond laser parameters (such as pulse length, intensity and wavelength), energy deposition within the molecule can be controlled to allow enhancement of parent ion production or generation of characteristic fragmentation patterns. In particular by reducing the pulse length to a timescale equivalent to the fastest vibrational periods in the molecule, we demonstrate how fragmentation of the molecule can be minimised whilst maintaining a high ionisation efficiency.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Fenilalanina
/
Temperatura
/
Acústica
/
Gases
/
Rayos Láser
Idioma:
En
Revista:
Phys Chem Chem Phys
Asunto de la revista:
BIOFISICA
/
QUIMICA
Año:
2012
Tipo del documento:
Article
Pais de publicación:
Reino Unido