8. Prepare standards for the calibration of the analyzer by adding a
known volume (e.g., 40 μl) glycine stock solution onto glass
fiber filters, and dry the filters (see Note 17).
9. Place dried filters on the aluminum circles, one filter per circle.
10. Fold with two clean forceps (cleaned with ethanol and burned).
11. Make into a small ball with a handheld plier.
12. Put the small balls into a 96-well plate (see Note 18).
13. Prepare the analyzer for analyses according to the operation
manual (see Note 4).
14. Place the aluminum balls in the autosampler of the analyzer
(see Note 19). Verify proper operation of the instrument with
reference material, and include blanks in the run (see Note 8).
4 Notes
1. Prepare 3–5 standards according to the level of DIC in the water
you are measuring.
2. Specifics of acid and carrier gas vary between instruments. We
have used 1% HNO 3 for Elektro-Dynamo URAS 3-E DIC
instrument (dissolve 11 ml concentrated nitric acid in ultrapure
water, fill up to a volume of 1000 ml, and store in a glass bottle).
3. The point is that no head spaced exists so that there is no gas
exchange. The bottles should preferably be kept in a refrigerator as temperature determines gas solubility, i.e., keeping them
warm would create bubbles inside, which would lead to underestimation of the concentration of inorganic carbon.
4. It is critical to have proper training before running the analyzer.
This will depend on the system that you are using, and it is
beyond the scope of this chapter to go into the details of the
operation of the instrument.
5. Calibration curve is prepared by plotting measured area of standards versus standard concentrations (linear regression).
6. In manual injection it is important that there is no air getting
into the sample chamber, so make sure that all air bubbles get
loose by tapping on the syringe, and push them out before
adding the last 300 μl into the sample chamber.
7. Samples must be pre-filtered in cases where calcium-containing
organisms are cultivated in order to measure only the dissolved
inorganic carbon.
68
Jaana Koistinen et al.
known volume (e.g., 40 μl) glycine stock solution onto glass
fiber filters, and dry the filters (see Note 17).
9. Place dried filters on the aluminum circles, one filter per circle.
10. Fold with two clean forceps (cleaned with ethanol and burned).
11. Make into a small ball with a handheld plier.
12. Put the small balls into a 96-well plate (see Note 18).
13. Prepare the analyzer for analyses according to the operation
manual (see Note 4).
14. Place the aluminum balls in the autosampler of the analyzer
(see Note 19). Verify proper operation of the instrument with
reference material, and include blanks in the run (see Note 8).
4 Notes
1. Prepare 3–5 standards according to the level of DIC in the water
you are measuring.
2. Specifics of acid and carrier gas vary between instruments. We
have used 1% HNO 3 for Elektro-Dynamo URAS 3-E DIC
instrument (dissolve 11 ml concentrated nitric acid in ultrapure
water, fill up to a volume of 1000 ml, and store in a glass bottle).
3. The point is that no head spaced exists so that there is no gas
exchange. The bottles should preferably be kept in a refrigerator as temperature determines gas solubility, i.e., keeping them
warm would create bubbles inside, which would lead to underestimation of the concentration of inorganic carbon.
4. It is critical to have proper training before running the analyzer.
This will depend on the system that you are using, and it is
beyond the scope of this chapter to go into the details of the
operation of the instrument.
5. Calibration curve is prepared by plotting measured area of standards versus standard concentrations (linear regression).
6. In manual injection it is important that there is no air getting
into the sample chamber, so make sure that all air bubbles get
loose by tapping on the syringe, and push them out before
adding the last 300 μl into the sample chamber.
7. Samples must be pre-filtered in cases where calcium-containing
organisms are cultivated in order to measure only the dissolved
inorganic carbon.
68
Jaana Koistinen et al.