Validation of liquid chromatography mass spectrometry (LC-MS) methods

Self test 3.2

1. The following calibration graph data were obtained for determination of p-fluorophenol by LC/ESI/MS. Is there enough data for linearity evaluation using statistical models?
C (ppb)Signal 1Signal 2
12974923.93168712.7
27488019.66342084.1
39731589.48301246.1
41134269413785834
51484296214119114
71751048219293589
103047217631279197
 

For use with ValChrom: st_3.2_4_linearity_0.xls 

2. The following calibration graph data were obtained for determination of p-fluorophenol by LC/ESI/MS. Is there enough data for linearity evaluation using statistical models?
C (ppb)Signal
514842962
1030472176
3061351801
5075849041
100129197238
 

For use with ValChrom: st_3.2_5_linearity.xls 

3. The following calibration graph data were obtained for determination of p-fluorophenol  by LC/ESI/MS. Construct a residual plot and evaluate the linearity of the calibration graph using the residual plot.
C (ppb)Signal (average of 3 measurements)
13256559
26863182
39233172
412586524
515588880
719099004
1029213011
For use with ValChrom: st_3.2_1_linearity.xls

4. The following calibration graph data were obtained for determination of p-fluorophenol  by LC/ESI/MS. Construct a residual plot and evaluate the linearity of the calibration graph using the residual plot.
C (ppb)Signal (average of 3 measurements)
515588880
719099004
1029213011
2046644306
3056559198
4066389856
For use with ValChrom: st_3.2_2_linearity.xls

5. Which of the following approaches are suitable for estimating linearity:

6. The following calibration graph data were obtained for determination of p-fluorophenol  by LC/ESI/MS.

Estimate the linearity of the data using the lack-of-fit test (at confidence interval 95%). First, find the number of degrees of freedom,  Fcalc and Ftab (with two decimal places) using the lack-of-fit test. Finally, make the decision whether the data is linear or not based on the results of the lack-of-fit test (taking into account the intercept).

C (ppb) Signal 1 Signal 2 Signal 3 Signal 4 Signal 5 Signal 6 Signal 7 Signal 8 Signal 9 Signal 10
1 2 974 924 3 626 041 3 168 713 3 388 090 3 227 503 3 096 385 3 311 505 3 106 431 5 850 908 6 858 138
2 7 488 020 6 759 442 6 342 084 6 897 963 6 930 675 6 194 285 6 484 264 6 825 409 10 338 656 11 143 377
3 9 731 589 9 666 680 8 301 246 9 989 337 9 033 645 8 479 358 8 802 637 8 521 330 15 127 722 16 820 448
4 11 342 694 12 631 045 13 785 834 11 875 416 11 307 826 13 630 759 9 703 166 10 914 339 20 571 744 16 632 365
5 14 842 962 17 804 564 14 119 114 14 028 887 13 275 118 13 448 179 13 562 132 13 657 833 19 488 337 21 625 881
7 17 510 482 20 492 942 19 293 589 20 508 735 20 729 582 19 119 414 20 355 196 17 187 445 26 006 437 27 962 282
10 30 472 176 25 887 661 31 279 197 25 998 848 29 162 834 28 176 825 23 353 950 33 486 848 25 592 373 35 715 119

For use with ValChrom: st_3.2_3_linearity_lof.xls

 

 

Number of degrees of freedom of the numerator:

Number of degrees of freedom of the denominator:

Fcalc (two decimal places, please use dot as decimals separator):

Ftab (two decimal places, please use dot as decimals separator):

The data is:    

7. The following calibration graph data were obtained for determination of p-fluorophenol  by LC/ESI/MS.

Estimate the linearity of the data using the lack-of-fit test (at confidence interval 95%). First, find the number of degrees of freedom, Fcalc and Ftab (with two decimal places) using the lack-of-fit test. Finally, make the decision whether the data is linear or not based on the results of the lack-of-fit test (taking into account the intercept).

The following calibration graph data were obtained for determination of p-fluorophenol  by LC/ESI/MS.

C (ppb) Signal 1 Signal 2 Signal 3 Signal 4 Signal 5 Signal 6 Signal 7 Signal 8 Signal 9 Signal 10
20 36 449 861 36 888 155 32 219 333 33 196 471 32 326 262 35 074 226 28 129 835 36 848 161 39 674 913 33 808 145
30 40 351 801 41 797 570 40 528 223 45 076 575 47 327 788 41 996 321 44 686 369 49 518 885 51 429 781 45 594 101
40 66 063 890 55 178 465 67 927 212 62 250 446 65 294 621 63 856 017 58 586 452 61 876 327 64 588 452 72 767 976
50 75 849 041 66 870 341 68 518 238 82 923 976 70 050 481 67 712 405 62 964 889 79 380 677 82 290 539 72 643 550
60 91 162 054 93 907 067 97 300 810 80 248 759 89 904 739 85 377 851 96 722 100 87 694 620 72 274 178 79 284 838
70 97 109 471 91 566 813 96 975 278 92 257 334 92 740 327 94 266 014 92 254 969 99 750 169 96 505 415 97 801 240
80 107 230 631 106 149 105 108 177 108 104 742 812 101 610 922 102 576 475 102 545 700 109 925 570 109 492 124 105 605 149
90 109 824 920 108 295 836 110 294 873 109 376 258 107 283 751 110 924 823 109 347 856 109 925 570 110 927 435 107 165 040
100 110 000 871 110 935 700 100 984 517 109 376 258 107 283 751 110 924 823 109 347 856 109 925 570 108 952 742 101 844 380

 

For use with ValChrom: st_3.2_6_linearity_lof.xls

Please evaluate the linearity of the corresponding calibration graphs by using the lack-of-fit test and decide whether it is justified to use a linear calibration model.

 

 

Number of degrees of freedom of the numerator:

Number of degrees of freedom of the denominator:

Fcalc (two decimal places, please use dot as decimals separator):

Ftab (two decimal places, please use dot as decimals separator):

The data is: