Tải bản đầy đủ - 0 (trang)
6 - Inductively coupled plasma spectrometry (ICP) (Soil & Plant Analysis Laboratory University of Wisconsin–Madison htt...

6 - Inductively coupled plasma spectrometry (ICP) (Soil & Plant Analysis Laboratory University of Wisconsin–Madison htt...

Tải bản đầy đủ - 0trang

148



CHAPTER 17  Analytical techniques



17.6.3 SAFETY

All chemicals should be considered potential health hazard. All relevant laboratory

safety procedures are followed.

The use of perchloric acid for a sample digestion must be conducted in a hood

designed specifically for perchloric acid. The user must be aware of the dangers involved using perchloric acid, such as the explosive nature of anhydrated perchloric

acid and its extreme corrosive nature.



17.6.4 INTERFERENCE

This method covers the analysis of over 30 elements in different kinds of samples by

ICP-OES and ICP-MS. A general discussion of interference is lengthy but not necessarily relevant to a specific element, which is especially true if the sample matrix is

not specifically defined. An enormous amount of literature is available to the analysis

of metals and nonmetals by ICP-OES and by ICP-MS. Reading the published articles

is recommended.

In this method, the solution contains less than 1000 ppm of dissolved solids for

ICP-OES and ICP-MS analysis. The major components are K, Mg, Ca, P, S, and Na.

These components either do not pose significant interferences with other elements/

isotopes or the potential interferences are well understood and controlled. Significant

interferences are not expected, although some specific elements and or isotopes may

be interfered.



17.6.5  MEASUREMENT BY ICP-OES

17.6.5.1  Sample preparation

Set 8-mL autosampler tubes in ICPOES sample racks. Transfer sample solutions

from 50-mL tubes to 8-mL tubes. For samples with extremely high analytes, the

samples may be further diluted. Add 3 mL of sample solution and 3 mL of 2% nitric acid to the 8-mL autosampler tube (2nd dilution. Nominal dilution factor = 200.

Y = 4 ppm).



17.6.6 MEASUREMENT

A detailed procedure is given in “elemental analysis of solution samples with ICPOES.” Digestion blanks are also measured with other samples.



17.6.7  MEASUREMENT BY ICP-MS

17.6.7.1  Sample preparation

Set 14-mL Falcon tubes in the ICPMS autosampler racks. Transfer the sample solutions to the Falcon tubes. Adjust the volume to 5 mL. Add 5 mL of 2% nitric acid.

Mix well. The nominal dilution factor is 200 and the IRS is 4 ppb of Rh. Since an internal reference standard is used, the volume inaccuracy during dilution is i­ rrelevant.



17.6 Inductively coupled plasma spectrometry (ICP)



If the concentrations of target elements are expected to be relatively high, the samples are further diluted, by either 2 + 8 dilution or 1 + 9 dilution. Otherwise, a sample

solution may be directly analyzed without any further dilution (ie, 10 + 0 dilution).

During the data processing in later stage, the nominal dilution factor is always 200,

whether the dilution is 1 + 9, 2 + 8, 5 + 5, or 10 + 0.



17.6.8 MEASUREMENT

A detailed procedure is given in “elemental analysis of solution samples with ICPMS.” Edit the menu depending on specific samples or analytical requests.



149



Page left intentionally blank



Appendices

COMMON BUFFERS

In this chapter, we describe the methods of preparation of some of the buffers, most

commonly used in the assay of enzymes required for plant physiological and histochemical studies.

The buffers have been arranged in an alphabetical order starting with their names.

These methods are not necessarily identical to those of the original authors. It is

advised that the users should redetermine the titration curves of majority of the buffers. These buffers have also been listed in Method in Enzymology, Vol. 1 (1955),

pp. 138–146.



APPENDIX I: CITRATE BUFFER

Stock solution

A :0.1 M solution of citric acid (21.01 g in 1000 mL water)

B :0.1 M solution of sodium citrate (29.41 g of C6H5O7Na32H2O in 1000 mL

water).

x mL of A + y mL of B, diluted to a total of 100 mL.

x



y



pH



46.5

43.7

40.0

37.0

35.0

33.0

31.5

28.0

25.5

23.0

20.0

18.0

16.0

13.7

11.8

9.5

7.2



3.5

6.3

10.0

13.0

15.0

17.0

18.5

22.0

24.5

27.0

29.5

32.0

34.0

36.3

38.2

41.5

42.8



3.0

3.2

3.4

3.6

3.8

4.0

4.2

4.4

4.6

4.8

5.0

5.2

5.4

5.6

5.5

6.0

6.2



Phenotyping Crop Plants for Physiological and Biochemical Traits. http://dx.doi.org/10.1016/B978-0-12-804073-7.00019-3

Copyright © 2016 BSP Books Pvt. Ltd. Published by Elsevier Inc. All rights reserved.



151



152



Appendices



APPENDIX II: SODIUM PHOSPHATE BUFFER

Stock solutions

A: 0.2 M solution of monobasic sodium phosphate (27.8 g in 1000 mL water).

B:0.2 M solution of dibasic sodium phosphate (53.65 g of Na2HPO4.7H2O or

71.7 g of Na2.HPO4, 12H2O in 1000 mL).

x mL of A + y mL of B, diluted to a total of 200 mL.

x



y



pH



x



y



pH



93.5

92.0

90.0

87.7

85.0

81.5

77.5

73.5

68.5

62.5

56.5

51.0



6.5

8.0

10.0

12.3

15.0

18.5

22.5

26.5

31.5

37.5

43.5

49.0



5.7

5.8

5.9

6.0

6.1

6.2

6.3

6.4

6.5

6.6

6.7

6.8



45.0

39.0

33.0

28.0

23.0

19.0

16.0

13.0

10.5

8.5

7.0

5.3



55.0

61.0

67.0

72.0

77.0

81.0

84.0

87.0

90.5

91.5

93.0

94.7



6.9

7.0

7.1

7.2

7.3

7.4

7.5

7.6

7.7

7.8

7.9

8.0



APPENDIX III: POTASSIUM PHOSPHATE BUFFER

pH



% K2HPO4 (Dibasic)



% KH2PO4 (Monobasic)



5.8

6.0

6.2

6.4

6.6

6.8

7.0

7.2

7.4

7.6

7.8

8.0



8.5

13.2

19.2

27.8

38.1

49.7

61.5

71.7

80.2

86.6

90.8

94.0



91.5

86.8

80.8

72.2

61.9

50.3

38.5

28.3

19.8

13.4

9.2

6.0



Appendices



APPENDIX IV: SODIUM ACETATE BUFFER

Stock solutions

A:0.2 M solution of acetic acid (11.55 mL in 1000 mL water).

B:0.2 M solution of sodium acetate (16.4 g of C2H3O2Na or 27.2 g of C2H3O2Na3H2O in 1000 mL water).

x mL of A+ y mL of B, diluted to a total of 100 mL.

x



y



pH



46.3



3.7



3.6



44.0

41.0

36.8

30.5

25.5

20.0

14.8

10.5

8.8

4.8



6.0

9.0

13.2

19.5

24.5

30.0

35.2

39.5

41.2

45.2



3.8

4.0

4.2

4.4

4.6

4.8

5.0

5.2

5.4

5.6



APPENDIX V: TRIS–HCl BUFFER (TRIS–HYDROXYMETHYL

AMINOMETHANE HYDROCHLORIC ACID BUFFER)

Stock solutions

A:0.2 M solution of (Tris-hydroxymethyl aminomethane) (24.2 g in 1000 mL

water).

B: 0.2 M HCl

50 mL of A + x mL of B, diluted to a total of 200 mL.

X



pH



5.0

8.1

12.2

16.5

21.9

26.8

32.5

38.4

41.4

44.2



9.0

8.8

8.6

8.4

8.2

8.0

7.8

7.6

7.4

7.2



153



154



Appendices



APPENDIX VI: 1M HEPES–NaOH pH 7.5 BUFFER

700 mL D.D.H2O, 238.3 g HEPES, and 5.5 g NaOH pellets added to adjust pH

to 7.5.



APPENDIX VII: PREPARATION OF STOCKS OF MACRO AND

MICRONUTRIENTS FOR HYDROPONICS EXPERIMENT

Concen­

Molecu­ tration

lar

of Stock

Macro­nutrients Weight Solution

Stocks

(g)

(1 M)



Concen­

tration

of Stock

Solution

(g/L)



Volume

of Stock

Solution/L

of Final

Solution

(mL)

Element mM



KNO3



101.10



1.00



101.10



6.0



Ca(NO3)2.4H2O

NH4H2PO4

MgSO4

NaNO3



236.16

115.08

246.49

84.99



1.00

1.00

1.00

1.00



236.16

115.08

246.49

84.99



4.0

2.0

1.0

1.0



Molecu­

lar

Micro­nutrients Weight

Stock

(g)



Concen­

tration

of Stock

Solution

(mM)



Concen­

tration

of Stock

Solution

(g/L)



Volume

of Stock

Solution/L

of Final

Solution

(mL)



Element



mM



ppm



KCl



74.55



50



1.0



Cl



50



1.77



H3BO3

MnSO4.H2O

ZnSO4.7H2O

CuSO4.5H2O

(NH4)6 MO7O24.

4H2O

Fe-EDTA



61.84

169.01

287.55

249.71

1235.9



25

2.0

2.0

0.5

0.5



3.728

1.546

0.338

0.575

0.125

0.081

1L



B

Mn

Zn

Cu

Mo



25

2.0

2.0

0.5

0.5



0.27

0.11

0.131

0.032

0.050



-



-



-



1.0



Fe



-



5.00



N

K

Ca

P

S

Mg



16,000

6000

4000

2000

1000

1000



ppm

224

235

160

62

32

24



Preparation of Fe-EDTA: Use amber color bottle for Fe-EDTA preparation. Dissolve 26.1 g of EDTA

in 286 mL of 1N KOH and mix with 24.9 g Ferrous sulfate (FeSO4.7H2O) and diluted to 1 L. Keep

overnight aeration for getting available state of Fe. One milliliter of this solution provided 5 ppm in 1 L.



APPENDIX VIII: PREPARATION OF ‘HOAGLAND SOLUTION’ FOR HYDROPONICS EXPERIMENT

Stocks Full Strength, mL/L

Stock Solutions

KNO3

Ca(NO3)2. 4H2O

NH4H2PO4

MgSO4

NaNO3 (M.W:85.0)

Fe-EDTA

Micronutrients

MgCl2 6H2O

(M.W:95.23)

Na2SO4 (M.W.142.05)

CaCl2 (M.W.110.99)

KCl (M.W.74.55)

NaH2PO4.2H2O

(M.W:156.01)

NH4Cl (M.W:53.46)



Com­

plete



-N



-P



-K



-Ca



-Mg



-S



-Fe



-Zn



-Mn



-B



-Cu



6

4

2

1

1

1

-



1

1

1

-



6

4

1

1

1

-



4

2

1

6

1

1

-



6

2

1

8

1

1

-



6

4

2

1

1

-



6

4

2

1

1

1@



6

4

2

1

1

-



6

4

2

1

1

1 (-Zn)

-



6

4

2

1

1

1 (-Mn)

-



6

4

2

1

1

1 (-B)

-



6

4

2

1

1

1 (-Cu)

-



-



4*

6*

2**



-



-



-



1

$1

-



-



-



-



-



-



-



-



-



2***



-



-



-



-



-



-



-



-



-



Appendices



*355 ppm of Cl; **46 ppm of Na; ***71 ppm of Cl; @ 35 ppm of Cl; $ 23 ppm of Na



155



Tài liệu bạn tìm kiếm đã sẵn sàng tải về

6 - Inductively coupled plasma spectrometry (ICP) (Soil & Plant Analysis Laboratory University of Wisconsin–Madison htt...

Tải bản đầy đủ ngay(0 tr)

×