One of the major facilities that has been developed as part of CARES is the Analytical Facility. This facility will house four major instruments as well as laboratory space specifically designed to support the faculty research. The four major instruments are an X-ray fluorescence spectrometer, an inductively coupled plasma - mass spectrometry system, a liquid chromatography - mass spectrometery system, and a gas chromatography - mass spectrometry system.
X-ray Fluorescence Spectrometer
A Spectro LAB-X 2000 has been ordered. This system uses a polarized x-ray beam to reduce the scattered x-rays that contribute background to the fluoresced x-ray spectra and thus, provide a higher signal-to-noise ratio. It has now been delivered, and shortly calibrations will be performed and appropriate standard operating procedures and quality assurance practices developed and implemented to assure quality XRF analyses of filter samples.
Inductively Coupled Plasma/Mass Spectrometry
A Thermo Electron X7 ICP-MS System has been ordered. The system provides high sensitivity in a benchtop unit. The innovative Infinity Ion lens ion optics, based upon a hexapole design with chicane ion deflector provides the lowest background specification of any quadrupole ICP-MS. This ion lens design uniquely enables simple field upgrade to Collision Cell Technology performance without affecting the normal (non-CCT mode) sensitivity or background.
Organic and Elemental Carbon
To analyze for carbon in particle samples, two approaches are available: NIOSH 5040 and the IMPROVE protocol. The NIOSH method is implemented in the Sunset Laboratory OC/EC analyzer while the IMPROVE protocol is available from the DRI Model 2001. We have both units and can provide either protocol.
Liquid Chromatography/Mass Spectrometry
A ThermoElectron LCQ Advantage Max LC-MS/MS Ion Trap System is available with a new high performance API source. We have ESI, APCI and Nano-Spray Probes. This system includes full scan, SIM, MS/MS product ion, SRM, and Zoom Scan capabilities. It has a range up to 2000 daltons. It can provide normalized collision energies. It also has MSn capability that permits multiple fragmentation of a specific mass fragment which will be very useful for qualitative analysis of the nature of the polymeric material extracted from the collected filters.
Gas Chromatography/Mass Spectrometry
We have two GC/MS systems including a BC-ion trap mass spectrometer (ThermoElectron Polaris-Q mass spectrometer with TRACE GC) and a GC- quadrupole mass spectrometer (ThermoElectron DSQ II with TRACE GC). The TRACE Gas Chromatograph is equipped with single channel digital pressure/flow control and is capable of multilevel temperature control with a maximum oven temperature of 450o C. A choice of injector type is available. The Polaris-Q mass spectrometer system uses a quadrupole ion trap mass analyzer with a mass range of 10-1000 amu and a mass resolution of 1 amu across the entire mass range. The MS/MS is capable of single ion isolation followed by collision-induced dissociation to fragment the preselected ion product ions, thereby increasing the selectivity and sensitivity of the analyte. The instrument is equipped with functions to allow for MS/MS of co-eluting compounds, rapid method optimization, and simultaneous full scan and MS/MS. the MS-MS capabilities offer the potential for increased identification of compounds that could not be separately identified in a traditional quadrupole mass spectrometer. The DSQ-II provides standard quadrupole analysis with excellent sensitivity for molecular marker species that are characteristic of specific source types.
Mass concentrations are measured by gravimetry using a Sartorius MC 5 Microbalance in our temperature and humidity controlled class 1000 clean room. There is continuous monitoring of temperature and relative humidity to ensure compliance with 40CFR50 Appendix L requirements for the 24-hour equilibration of the filter before and after exposure to the ambient aerosol.
In order to prepare the samples for ICP/MS analysis, they need to be acid digested to put the sample into solution. We have acquired a CEM MARS-Xpress. It can produce temperatures of up to 260 C and pressures of 500 psi for rapid sample digestion. This system permits the processing of up to 40 samples at a time with individual monitoring of sample temperatures. Thus, it has much higher throughput than the competitive systems.
To prepare the samples for analysis, we have a DIONEX ASE300 Accelerated Solvent Extraction system. This unit uses elevated temperature and pressure in a stainless steel container that permits rapid extraction of the samples with a much smaller volume of solvent than would be typically employed in a conventional Soxhlet extraction system. ASE independently controls temperature and pressure conditions for each sample cell. This control is critical for high analyte recovery and reproducibility, even with samples that contain varying amounts of moisture. ASE is accepted for use in U.S. EPA SW-846 Method 3545A, which can be used in place of Methods 3540, 3541, 3550, and 8151. Method 3545A can be applied to the extraction of base/neutrals and acids (BNAs), chlorinated pesticides and herbicides, polychlorinated biphenyls (PCBs), organophosphorus pesticides, dioxins and furans and total petroleum hydrocarbons (TPH).