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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- injection port • Temperature (thermal degradable?) • Split or splitless • Split ratio • Injection volume
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
Limit of linearity (LOL) Limit of quantitation (LOQ) Method detection limit (MDL) Detection limit for trace analysis
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
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
FAQs –QA/QC • Quality control • systematic processes that ensure test results are designed and produced to meet the requirements • Spike • Duplicate • Spike duplicate
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
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.
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.