Our laboratory is equipped with high-pressure appartus for hot-water fractionation, OC/EC analyzer (Sunset laboratories), GC Agilent 6890 with flame ionization (FID), flame photometric (FPD) and MS (with electron ionization as well as positive and negative chemical ionizations) detectors. For biofuels analysis, we have purchased Agilent GC 7890 with FID, thermal conductivity detector (TCD) and MS detectors.
Chemistry Department is equipped with additional chromatographic mass spectrometric instrumentation currently maintained and operated by our research group. The instrumentation includes Agilent 1100 HPLC with an autosampler and a diode array detector coupled to a high resolution time of flight (TOF) MS with electrospray and atmospheric pressure ionization sources. HPLC with ion trap MS Esquire from Bruker is available in the same laboratory. Additional, GC/MS instrument (Agilent Model 5972) with electron impact ionization is available.
We have a new Agilent 7890 capillary gas chromatograph. This system is equipped with Agilent 7683 automatic liquid sampler and programmed temperature vaporizing (PTV) injection port. The GC can be interfaced to a flame ionization detector (FID), thermal conductivity detector (TCD), and Agilent 5975 MS detector. The MS operates in electron ionization (EI) mode. A microfluid 2-way splitter allows for simultaneous data acquisition using two different detectors. The characteristics of the Agilent 7890 capillary GC make it suitable for sensitive biofuel analysis.
Our Agilent GC6890 is equipped with split/splitless and on-column injectors. Three detectors are available for analysis. This GC is interfaced into the Agilent MSD 5975C with inert source. The MS can be operated in hard (EI) or soft (CI) ionization mode. Two additional detectors, FID and FPD (flame-photometric detector), are available for analysis. Multipurpose Gerstel MPS2 autosampler installed on this system allows for automated liquid, headspace or SPME injections.
This system is dedicated for the trace analysis of particulate matter.
Our lab also maintains Hewlett-Packard (HP) 5890 Series II Plus capillary GC coupled to HP 5972 MS detector operating in EI mode. The HP 5890 GC equipped with HP 6890 ALS allows for split/splitless injection. This instrument is used for teaching purposes as well as for valuable analysis of various samples.
Our group maintains departmental LC1100, which is equipped with the autosampler, DA detector and interfaced into the Bruker LC-Esquire ion trap MS. Two ionization sources, ESI and APCI, are available for the analysis. Ion trap MS allows for MS/MS experiments, which can be useful for compound identification.
Our research laboratory houses LC/MS Agilent G1969A Time-of-Flight. This high resolution TOF MS allows distinguishing compounds with a 5 ppm mass accuracy. This can be especially useful for characterization of complicated matrixes containing numerous compounds with similar molecular ions. Two types of atmospheric ionization sources, electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) allow for analysis of a wide range of analytes. Particularly, such a difficult matrix as a flaxseed extract was already successfully characterized by the LC/MS TOF. Analysis employing in-line detection with DAD and MS TOF can be performed with this instrument.
This instrument (Sunset Laboratories) is used for determining total carbon content (TC), organic carbon (OC) and elemental carbon (EC) from aerosol samples .
Carbonaceous samples are submitted into a quartz oven on a 1.5 cm2 quartz filter punch. The carbon is then volatilized with increasing temperature in an inert helium atmosphere followed by a mixture of helium and oxygen evolving organic carbon and elemental carbon respectively. The evolved carbon is oxidized over a MnO2 catalyst to CO2 and subsequently reduced to methane which is then detected by a flame ionization detector (FID).
During the analysis, portion of EC pyrolyses prematurely. In order to determine the split point between OC and EC, this instrument employs a correction by either laser transmittance or reflectance.
This unique system works based on the principle that the polarity of water changes with increasing temperature while held under sufficient pressure to maintain the liquid state. Purified water from a DirectQ (Millipore Inc.) with TOC residue less than 5 ppb is pumped using a Varian Prostar 210 HPLC pump through the high pressure sample/extraction vessel, which is placed in a Hewlett Pacard 5890 GC oven. The extract flows to a heated high pressure needle valve (outside the oven) ensuring sufficient pressure essential for extraction with LIQUID water. The extract is then cooled as it passes through stainless steel tubing which is coiled in an ice bath to prevent analyte volatilization once it reaches the collection vial. The system allows for extraction in the temperature range from 25–370 °C with water maintained in liquid state.
This extraction unit has proven to effectively fractionate different polarity organics based on the different temperatures of the extraction. It is used to fractionate extracts from various PM samples as well as aerosol filter samples.
Our laboratory is equipped with a Cary 50 UV-Vis spectrophotometer. This spectrophotometer allows for high absorbance range (up to 10 Abs) measurements with relatively high scan speed (24 000 nm per minute). Cary-50 is equipped with a Xenon lamp making possible for analysis of photosensitive samples. Besides, the design of the instrument can operate with the sample compartment open or closed which may be extremely useful for some experiments. Special accessory, microplate reader, allows for a high throughput analysis in microliter volumes.
This sampler consists of a 92 LPM PM2.5 cyclone followed by a 600 mm 8-channel annular glass denuder, a two-stage 90 mm filter pack (all from URG Corp.), an Alicat Scientific mass flow controller and an Air Dimensions high speed pump. This sampler is capable of collecting gas phase as well as particulate phase contaminants from aerosol samples. We are currently working in collaboration with the Chemical Engineering department on building a sampling probe for an air plane thus its use in atmospheric studies as well. We have also implemented an additional interface for sampling directly from the exhaust of a jet turbine engine. This will later be used for obtaining particulate samples from JP8 jet fuel and biofuels.
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