My Research

 

I am a third year graduate student working with Professor Barbara. J. Garrison. My research involves carrying out Molecular dynamic (MD) simulations on matrix assisted laser desorption ionization (MALDI).


MALDI is an ionization technique used in mass spectroscopy to study the process in which analyte molecules (mainly biomolecules like polypeptides) free themselves from the matrix (crystalline molecular solid) during ablation. The matrix acts as a support for the analyte molecules and prevents them from being destroyed during ionization. The bio-molecules tend to be fragile and may fragment, so to avoid the thermal decomposition of these analyte molecules the intensity of the laser or the laser fluence (laser energy per unit area) can be controlled. Consequently, MALDI is a technique which produces intact protonated molecular analyte species and is therefore also referred to as “soft” ionization technique. Even though MALDI is a popular technique, clear understanding of ionization process and the chemistry involved in matrix-analyte interactions is still under investigation and an active area of research.

Image of tripeptide(Ala-Ala-Ala) analyte (blue) partially embedded in a 2,5 dihydorxy benzoic acid matrix (purple) in a MALDI simulation setup

 

There lies discrepancy between experimental and theoretical work in this area. The experimental data shows a big molecular ion peak showing that the analyte molecules free themselves from the matrix, however, the simulations show the analyte molecules attached to the matrix. The key point of the investigation is to study the analyte molecule-matrix interactions by changing the nature of the analyte molecule.

 

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Links

 

 

Contact

104 Chemistry Building

Department of Chemistry

Pennsylvania State University

University Park, PA 16802

Email: sxn225_at_psu.edu

Phone: 814-863-2108