Chemical Analysis Laboratory

Sample Preparations

Dry ash method - 0.5 gm of dried ground plant tissue is ashed in a porcelain crucible at 500°C for 4 hours and cooled. 10 ml of a plant buffer solution is added and allowed to settle before analysis. The 965 ICP is set up with a 20 element program for plants. NIST plant standards (apple leaves, pine needles) are used to confirm the proper calibration for this matrix. $10.00/spl
Wet digest - 1-2 gm of dried ground plant tissue is placed into an acid washed erlinmeyer flask and 10 ml of nitric acid is added. The flask is covered with a watch glass and allowed to sit overnight. On a 90°C hot plate, nitric and hydrochloric acid are added to digest the plant tissue. $25.00/spl

Double Acid Extraction - 5 gm of air dried 10-20 mesh soil is placed into a polypropylene tube with 20 ml of a dilute HCl and H₂SO₄ solution. Tubes are placed in a shaker for 5 minutes and then filtered. $10.00/spl
EPA method 3050 - 1-2 gm of dried 10-20 mesh soil is placed into a conical beaker and 10 ml of 50% nitric acid is added. The sample is covered with a watch glass, heated to 90°C on a hot plate, refluxed for 10 minutes (repeated if necessary), evaporated to 5 ml, and cooled. H₂O₂ and HCl is added and refluxed for 15 additional minutes and the sample is filtered or allowed to settle. $25.00/spl

Persulfate digestion for total nitrogen, total phosphorus in waters - 5 ml of sample is placed into a clean culture tube with polypropylene lined caps. Next 1 ml of persulfate oxidizing reagent is added and placed into an autoclave at 19 psi for a minumum of 45 minutes. $25.00/spl
EPA method 3010 - 100 ml of sample is poured into a clean beaker and 3 ml of nitric acid is added. The solution is covered with a watch glass, placed on a hot plate, and refluxed at 90°C until it evaporates to ~5 ml. An additional 3 ml of nitric acid is added, refluxed for 10 minutes, and cooled. 10 ml of 50% HCl is added and refluxed for 15 minutes, cooled, then the volume is adjusted back to 100 ml. $25.00/spl

Dry bone sample (1-2 gm if possible) is placed in an oven at 80°C overnight. The bone is muffled in a clean 200 ml beaker at 500°C for 4 hours, 5 ml of aqua regia is added, and the beaker covered with a watch glass heated on hot plate at 90°C until dry. 100 ml of the plant buffer solution is added and then analyzed. $25.00/spl

Dry peanuts are finely chopped and then 0.5 gm is weighed and placed into a 20 ml vial or beaker and ashed for 8 hours at 500°C. This is then cooled, 4-8 drops of concentrated nitric is added, and the sample is heated on a hot plate until almost dry. Samples are returned into the muffle furnace for 1 hour at 500°C until the ash is white, and 10 ml of the plant buffer solution is added and then analyzed. $25.00/spl

For further information contact Becky Auxier (706) 542-6031 auxier@uga.edu

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