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FAQs- before analyzing your sample

FAQs- before analyzing your sample. FAQs- injection port. Temperature (thermal degradable?) Split or splitless Split ratio Injection volume. Split/splitless injection port. FAQs –column and oven. Column selection Polarity (DB5-ms, DB-17, DB-Wax) Chirality (HP-Chiral ß column)

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FAQs- before analyzing your sample

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  1. FAQs- before analyzing your sample

  2. FAQs- injection port • Temperature (thermal degradable?) • Split or splitless • Split ratio • Injection volume

  3. Split/splitless injection port

  4. FAQs –column and oven • Column selection • Polarity (DB5-ms, DB-17, DB-Wax) • Chirality (HP-Chiral ß column) • cis/trans form (HP-88) • Length of column • H = L/N

  5. FAQs-peaks

  6. Experimental resolution

  7. van Deemter equation

  8. FAQs-peaks

  9. FAQs-peaks

  10. FAQs-peaks

  11. Detection limit for trace analysis LOQ MDL

  12. Detection limit for trace analysis MDL

  13. Limit of linearity (LOL) Limit of quantitation (LOQ) Method detection limit (MDL) Detection limit for trace analysis

  14. FAQs –qualification • Retention time only • Dual column with certify reference materials • Retention time with mass spectrum • Identification power of ion (at least 4) • MS: 1 IP • MS/MS and HR MS: 2 IP

  15. FAQs –QA/QC • Quality assurance • systematic processes that provide confidence in a suitability of analytical process for its intended purpose. • Blank (field, reagent, matrix) • Calibration check sample

  16. FAQs –QA/QC • Quality control • systematic processes that ensure test results are designed and produced to meet the requirements • Spike • Duplicate • Spike duplicate

  17. FAQs –sequence • Reagent blank • Calibration C1-C5 (at least 5 points within 1 order) • Calibration check CK1 • Sample S1-Sn (≦ 10 for environmental analysis, ≦ 20 for common practice) • Spike SK1 • Duplicate D1 • Spike duplicate sample SD1 • Sample Sn+1-S2n • Spike SK2 • Duplicate D2 • Spike duplicate sample SD2 • Calibration check CK2

  18. FAQs –internal standard • An internal standard in analytical chemistry is a chemical substance that is added in a constant amount to samples, the blank and calibration standards in a chemical analysis. • This substance can then be used for calibration by plotting the ratio of the analyte signal to the internal standard signal as a function of the analyte concentration of the standards.

  19. FAQs –internal standard • This is done to correct for the loss of analyte during sample preparation or sample inlet. The internal standard is a compound that matches as closely, but not completely, the chemical species of interest in the samples, as the effects of sample preparation should, relative to the amount of each species, be the same for the signal from the internal standard as for the signal(s) from the species of interest in the ideal case. • Adding known quantities of analyte(s) of interest is a distinct technique called standard addition, which is performed to correct for matrix effects.

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