KCS

We have studied the life history of a charged droplet, from formation at the ESI tip to the completely desolvated ions that are eventually formed. These studies have led to the development of a new method for the controlled extraction of desolvated ions from neutral droplets in a process called field induced droplet ionization (FIDI). This “soft sampling” methodology facilitates observation of molecular clusters and non-covalent complexes. Of particular interest are clusters that have unique stability, such as the homochiral serine octamer, and the controlled covalent coupling within molecular clusters, the formation of ATP from anionic salt clusters of AMP, the selective phosphorylation of serine in peptides, and the processing of organic atmospheric aerosols being examples. For applications in proteomics, we have identified reagents which can recognize and bind to specific amino acids in peptides and proteins, that has led to the development of novel biomimetic reagents.