One of the major facilities that has been developed as part of CARES is the Analytical Facility. This facility houses a number of major instruments as well as laboratory space specifically designed to support the faculty research. The four major types of instruments are an X-ray fluorescence spectrometer, an inductively coupled plasma - mass spectrometry system, liquid chromatography - mass spectrometery systems, and gas chromatography - mass spectrometry systems including a 2-D gas chromatograph/high resolution mass spectrometer system.
X-ray Fluorescence Spectrometer
A SPECTRO XEPOS + Gas Purge (8 Targets) is available for XRF analysis This system includes 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. The samples are held in an He atmosphere to reduce volatilization losses in the more typical vacuum systems. It is used routinely to analyze 25, 37 and 47 mm filers.
Inductively Coupled Plasma/Mass Spectrometry
A Thermo Electron ICP-MS X Series II System is available. 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. This system has been used extensively in the analysis of air filters, soils/sediments, and biological samples particularly fish.
Organic and Elemental Carbon
To analyze for carbon in particle samples, two approaches are available: the 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.
We also have a Waters Xevo quadrupole time-of-flight (QTof) mass spectrometer (MS). This exact mass (>10,000 res) benchtop instrument is one of the most sensitive and versatile benchtop QTof systems ever produced and is equipped with the only commercially-available MS that utilizes an MSe configuration to collect “all of the data all of the time”. Using paired low and high energy channels, the system efficiently performs data independent MS/MS experiments at unparalleled speeds and sensitivity, maximizing the information obtained with minimal sample loss. A Waters ACQUITY UPLC System consisting of an ACQUITY UPLC Sample Organizer, Column Manager and Heater/Cooler, Binary Solvent Manager and Sample Manager provides liquid chromatographic front end to this system. In addition, an Agilent 7890 can be attached to the QToF enabling Atmospheric Pressure Gas Chromatography (APGC) mass spectrometry experiments. This newly developed technique provides a softer ionization (less fragmentation) for volatile/semi-volatile analytes increasing the signal of the molecular ion. Combining the exact mass resolution, increased molecular ion sensitivity and MSe configuration, the APGC-QToF-MS allows for enhanced identification of organic species in complex matrices.
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.
Multidimensional Gas Chromatography
We are in the process of purchasing a LECO Pegasus 4D GCxGC-TOFMS. The latest addition to the chromatography market, this state-of-the-art system combines comprehensive gas chromatography with the exact mass resolution of a Pegasus HT TOFMS. This instrument will be used for analyzing complex samples, primarily for emerging contaminants. No longer are we limited to 2-D chromatography and nominal mass resolution, or 1-D chromatography and exact mass resolution. The new system combines multi-dimensional chromatography and high resolution mass spectrometry for unmatched paired chromatographic and mass resolution. With the LECO GCxGC, hundreds-to-thousands more compounds are chromatographically resolved with exact mass identification for a truly comprehensive separation of the sample matrix.
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).
The lab also has a Fluid Management Systems (FMS) PowerPrep SPE Automated One-Step Extraction and Concentration System. The PowerPrep SPE system automates existing manual SPE techniques and replaces older manual Liquid-Liquid Extraction techniques and outdated semi-automated instruments. It combines extraction, drying and concentration into one step.
We also have a Fluid Management Systems (FMS) PowerPrep automated Gel Permeation Chromatography (GPC) system capable of separating synthetic macromolecules such as pesticides, PCBs, PAHs etc. from interfering compounds. It uses glass or polypropylene columns packed with styrene-divinylbenzene resin beads, and can process from 1 to 30 samples sequentially.
Mercury AnalysesCARES has a state-of-the art mercury analysis laboratory that can analyze solids, water and biota for total mercury and methyl mercury. Instruments include: a Milestone’s DMA-80 Direct Mercury Analyzer. The DMA-80 requires no sample preparation and delivers results, comparable to those obtained on CVAA and ICP-MS, in as little as 5 minutes; a Tekran 2600 for analysis of ultra-trace levels of total mercury in laboratory prepared environmental samples (water, biota, soil, sediments, gas cartridges, effluents and more). The Series 2600 is capable of providing a fully automated implementation of EPA Method 1631. This method is capable of measuring waters and digested solids with detection limits over 10X lower than required; and a Tekran 2700 Methyl Mercury Analysis System which offers an automated solution for complex and time consuming manual techniques. The 2700 is a fully-integrated, gas chromatography, cold-vapor atomic fluorescence spectrophotometer (GC-CVAFS). The 2700 can analyze distilled waters, extracted or distilled tissues and solids, and allows direct analysis of suitable water samples.