Calibration Curves (Venton)
- Page ID
- 281548
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The following are hypothetical calibration curves made with a Gas Chromatography instrument (although no GC knowledge is needed for this question).
Reference: Calibration. Rodríguez Cuesta, Boqué, Vander Heyden, LCGC Europe. 2007 Volume 20, Issue 6, pg 349–356.
- Looking at curves A and B (blue and red): which method has the greater sensitivity? Why?
- Looking at Curves A and C (blue and green): Which method has the greater sensitivity? Why?
- Curve C has an offset (i.e. intercept is non-zero). What types of error could be responsible for that offset? Name a specific example of what could cause that offset.
- Calibration curve D is nonlinear. If you were making and using this calibration curve, what are some potential problems you might encounter and how would you handle them?
- Sometimes people do a one point calibration to estimate the concentration. Would this be a valid approach to approximate curve A? How about curve C? Why?
- If the standard deviation for the blank is 500, what is the LOD for curve A?
- A. For curve A, you run an unknown and your response is 55,000. What is your amount in your sample?
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For curve A, you run an unknown and your response is 150,000. What is the amount in your sample?
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Contributors and Attributions
- Jill Venton, University of Virginia (bjv2n@eservices.virginia.edu)
- Sourced from the Analytical Sciences Digital Library