Mechanism of Protein Molecule Isolation by IR Laser Ablation of Droplet Beam.

Gas-phase isolation of bovine serum albumin (BSA) from aqueous solutions is performed by IR laser ablation of a droplet beam. Multiply charged BSA ions (positive and negative) were produced by the IR laser irradiation onto a droplet beam of aqueous BSA solutions with various pH values prepared by addition of hydrochloric acid or sodium hydroxide to the solution. The isolation mechanism was discussed based on the charge state of the isolated BSA ions.