Pulsed Valve Matrix-assisted Ionization

DOI: 10.1039/C7AN00489C

PV MAI Schematic
Pulsed valve matrix assisted ionization schematic.

We have developed a new ionization approach for matrix-assisted ionization with high temporal resolution using an electrically actuated pulsed valve. Matrix and analyte samples are deposited on a thin metal foil and placed at the inlet of an ambient ionization mass spectrometer. When the pulsed valve is actuated, a short puff of high pressure gas impinges on the foil and ejects particulate from the sample on the opposite side. Highly charged ions are formed from the particles at the mass spectrometer inlet. Using this source, multiply charged protein ions are produced within a selectable 4 second time window.

IR Opolette 2940

IR Opolette 2940 side view.
IR Opolette 2940 side view.
Another laser and the second from OPOTEK this year: an IR Opolette 2940. It is fixed wavelength at 2940 nm for no other reason than that is the Er:YAG laser wavelength. It is possible to manually adjust the internal optics to generate light from 2700 to 3100 nm.

OPOTEK IR Opolette head (right) and Quantel
OPOTEK IR Opolette head (right) and Quantel

This laser has its roots in the STTR grant that I had with OPOTEK starting in 2001 (awarded when I was at Emory but moved immediately to LSU in the first year of Phase I). Our goal was to build an OPO with the capabilities of the Mirage 3000B but in a smaller package.

OPOTEK Opolette 2940 laser head.
OPOTEK Opolette 2940 laser head.

The left port gives access to the Nd:YAG laser fundamental at 1064 nm and the right port is the 2940 nm mid-IR at about 3 mJ per pulse at 20 Hz. Plenty of energy when focused to efficiently ablate thin films (similar to our wavelength tunable IR Opolette which you can see ablating things here.)

Minilite Laser

The Continuum Minilite 532 nm laser arrived February 25. This was funded by a LIFT2 grant.

Continuum Minilite laser crate.
Continuum Minilite laser crate.
Label on the Minilite crate – can't get away from politics even in lab!
Label on the Minilite crate – can’t get away from politics even in lab!
Uncrating the Minilite.
Uncrating the Minilite.
The Mililite laser uncrated. Add some cooling water and we should be ready to ablate some genomic material.
The Mililite laser uncrated. Add some cooling water and we should be ready to ablate some genomic material.