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Chapter 5: Q9P (page 114)

Consider a sample that contains analyte at the detection limit defined in Figure. Explain the following statements: There is approximately a 1%chance of falsely concluding that a sample containing no analyte contains analyte above the detection limit. There is a50%chance of concluding that a sample that really contains analyte at the detection limit does not contain analyte above the detection limit.

Short Answer

Expert verified

The following statements was explained.

1. Above the detection limit approximately

1%

chance of falsely concluding that the sample does contain no analyte.

2. Above the detection limit approximately50%chance of concluding that the sample doesn't contains analyte.

Step by step solution

01

The detection limit

The concentration of an analyte that produces a signal with a standard deviation three times that of a blank signal.

The minimum detectable concentration =3sm

Where,

S=Standard deviation.

m=Slope of linear calibration curve.

02

Explanation of statements

The first statement means that since there is approximately 1%chance of false negative results showing up, there will also be approximately 1%of samples (that do NOT contain the analytes) that will respond with a signal above the detection limit.

For the second statement -- which is a hypothetical situation for false positive results -- means that50% of the samples containing the analyte with a signal going below the limit of detection.

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