Services
The facility offers analyses of prepared liquid, gas, and solid samples. Below is a list of the analytes and sample types for each instrument housed in the facility. Facility personnel prepare standards and quality control samples for all analyses.
Researchers are expected to process samples for the listed analyses in separate laboratories.
Please see information below, or contact us, about how to prepare your samples or if you have any questions regarding the sample requirements (e.g., preservation, sample amount, labeling requirements, etc.) for each analysis.
Inorganic N
OI Analytical Flow Solution IV (OI Analytical Corp., College Station, TX, USA). This instrument is for filtered liquid samples only (such as water or soil extracts). This instrument can analyze: ammonium (NH4+), nitrite + nitrate (NO2-/NO3-), and nitrite only (NO2-). Inorganic N concentrations are calculated as elemental concentrations and should be reported as NO3-N and/or NH4-N.
Preparation requirements: Samples must be filtered through a 0.4 μm membrane prior to analysis. We recommend using polycarbonate membranes to filter samples as Whatman filters can contain ammonium.
Submission requirements: Each sample must be labeled with a date, investigator name, project name, ID system, and background solution (e.g. 2 N KCl or H2O).
TOC, TC and/or TN
Shimadzu TOC-L/TNM-L (Shimadzu Corp., Kyoto, Japan). This instrument is for filtered liquid samples only: water or extracts. This instrument can analyze: Total Organic Carbon (TOC), Total Carbon (TC), and Total Nitrogen (TN). The primary configuration uses a high salt combustion tube, for samples such as 0.5 M K2SO4 soil extracts. The instrument must be reconfigured with a standard combustion tube for water samples.
Preparation requirements: Samples must be filtered through a 0.4 μm membrane prior to analysis. We recommend using polycarbonate membranes to filter samples as Whatman filters can contain ammonium.
Submission requirements: Each sample must be labeled with a date, investigator name, project name, ID system, and background solution (e.g. 0.5 M K2SO4 or H2O).
Total CN, CHN, CHNS and/or O
Thermo Flash 2000 CHNS/O Elemental Analyzer (CE Elantech Corp., New Brunswick, NJ, USA). This instrument can analyze solid or liquid samples (requiring special preparation) for percent carbon (C) and nitrogen (N) or total organic carbon (TOC) using dry combustion followed by gas chromatography.
Preparation requirements: Solid samples must be dried and ground to a fine powder. We recommend using a mixer mill (“ball-grinder”) or mortar and pestle to achieve a powder-like consistency (spice/coffee grinders and Wiley mills are not adequate for sample homogenization). Samples must be weighed on a microbalance (00.000 mg) into a tin capsule. Capsules should be condensed to a “square-like” package to prohibit sample rolling, spilling and to remove excess air from the sample. It is recommended that tin capsules are purchased directly from CE Elantech. Samples should be housed in well-plates or individual vials.
Contact the facility for appropriate weights to use. The following are general guidelines for plant tissues and soil:
- Percent CN in solid samples: Appropriate sample weights are determined by the percent of the element in the sample (e.g., soil with %C < 10% use 40.000-80.000 mg; organic soils like peat use ~10.000 mg; plant tissue use 5.000-10.000 mg).
Other types of solid samples include filter papers and animal tissues, please contact us for more information.
Liquid samples can be analyzed by placing absorbent in the foil cup and pipetting in a small amount of liquid sample. The tin cup must then be sealed. Please contact us for more information.
Submission requirements: Each sample plate must be labeled with a date, investigator name, project name, ID system, and type of sample. Corresponding weights for each sample must be submitted. The facility will prepare standards and checks.