LILBID (Laser Induced Liquid Bead Ion Desorption)
![droplet generator](droplet_generator.jpg)
Microdroplets (50 μm diameter) of the sample solution are introduced into vacuum with the help of an on demand droplet generator. There they are irradiated one by one by a mid-IR laser which runs at the same frequency (10Hz).
The laser wave-length is tuned to the absorption maximum of water at around 2.94 μm - the H-O stretching vibration of water. The absorbed laser energy leads to the explosion of the droplet, releasing the biomolecular complex ions into vacuum, where they can be analysed by a time-of-flight mass analyser. The incomplete ion neutralisation process leads to gas phase ions whose charge state mimic the charge states of the complexes in solution.
![Laser dissotiation](complex%20dissociation-01.jpg)
Variation of one parameter - the intensity of the desorption laser - determines the harshness of the method. Under soft conditions the complexes stay intact, while at harsh laser conditions the non-covalent bonds break, revealing the constituting subunits. At medium conditions stronger bonds can stay intact, exposing stable subcomplexes.
![LILBID 1st generation](LILBID_1_a.jpg)
Instrumentation:
LILBID instrument
1st generation
![LILBID 2nd generation](LILBID_2_a.jpg)
LILBID instrument
2nd generation