Northwestern University
Mass Spectrometry Facility at ASL

Instruments

Agilent 6210 LC-TOF with Agilent 1200 HPLC introduction

This mass spectrometer system is capable of measuring exact mass of molecules with an accuracy of ±2 ppm. ESI, APCI, APPI ionization available. Please contact Saman to obtain sample preperation guidleines.

LCQ Advantage

The LCQ no longer changes solvents. Methanol and dichloromethane are available 7 days / week. For ACN / water, used the MSD1100.

LCQ Operation

Agilent MSD1100

Sample introduction using Agilent 1100 HPLC system. Methanol, ACN and water available 7 days / week.

MAT900 

	Heatable/coolable direct insertion probe Desorption CI probe
	GC (packed column, capillary column)
	FAB probe (standard, continuous flow)
	LC (TSP, flow FAB)

This mass spectrometer system is capable of measuring exact mass of molecules with an accuracy of ±2 ppm or better, depending on the nature and cleanliness of the samples. The FAB ion
source (now converted to LSIMS, liquid secondary ion mass spectrometry) 
is a soft ionization source; it enables us to work with high mass, nonvolatile/polar molecules to get molecular weight and structural information.

The sample size requirement is in the nanomole range for most modes of operation. However, for accurate mass measurements (i.e. high resolution) more sample is required, not only for the low ion transmission but also for duplicate measurements. Normally, 0.01 to 0.1 microgram of sample should be sufficient.

PE Voyager DE-Pro MALDI-TOF Mass Spectrometer

The Perseptive Biosystems Voyager Pro DE is a time of flight (TOF) mass spectrometer with a MALDI (matrix assisted laser desorption ionization) ionizer. It employs a delayed extraction technique for improved resolution and can be run in either a linear or reflectron configuration as needed for your application. As the name suggests, this instrument uses a laser to desorb and ionize your sample. The sample must be dissolved in an appropriate matrix for analysis. Please consult with the ASL Mass  Spectrometry Specialist for advice on matrix choices and other sample preparation considerations. 

This instrument is particularly useful for high molecular weight samples such as proteins and is capable of analyzing samples containing species with molecular weights greater up to and beyond 100,000. Sample fragmentation, and therefore protein sequencing, is possible when the instrument is run in the post source decay mode.

Service with this instrument may be requested in a staff run mode or if it is anticipated that samples will be run frequently with this instrument, individual users may be trained to operative the MALDI-TOF mass spectrometer themselves. Please contact Saman Shafaie with any questions.

HP 6890 GC/MSD

The Hewlett Packard 6890 GC/MSD is a benchtop gc/ms available for your individual use after appropriate training. The HP6890 GC/MSD is comprised of a HP 6890 GC interfaced to a HP 5972 Mass Selective Detector Quadropole Mass Spectrometer. The system uses electron impact (EI) ionization and is capable of performing full mass scans or selective ion monitoring  (SIM). The GC is set up for capillary columns. All samples have to be introduced through the GC interfaces, since no direct probe capability is available for this instrument. Several different types of capillary columns are available for the GC. 

Since this is a community instrument, sample cleanliness is imperative. Any nonvolatile compounds that you inject onto the column will be left behind and will cause future column and/or instrument problems for you and all other users. All metals must be removed from your samples and no acids or bases should be injected. You must enter the identity of your sample in the instrument logbook so that instrument problems can be traced to the injected compounds. If you have any concerns about whether your sample is appropriate for this instrument, check with Saman Shafaie.

Specifications:

Mass Spectrometer:

	Full Scan: Mass Range: 1.6-700 amu Scan Speed: Up to 1800 amu/sec with 1 amu resolution Sensitivity: 10pg of Hexachlorobenzene yields a signal to noise of >10:1
	Selective Ion Monitoring: Mass Range: Up to 50 groups of 30 masses/group Sensitivity: 200fg of Hexachlorobezene yields a signal to noise of >10:1