The half-life of a radioisotope that decays to 12.5 % of its radioactivity in 12 years should be calculated. Concept introduction: The rate at which a radioactive sample decays is called an activity of a sample. Half-life is the time required for one half of a sample to disintegrate.

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Liquid chromatography has been used to track the concentration of remdesivir (a broad-spectrum antiviral drug, structure shown at right) in COVID patients undergoing experimental treatments. Intensity The authors provide the following details regarding standard solutions preparation: HN CN HO OH NH2 Remdesivir (RDV) stock solution (5000 µg/mL) was prepared by dissolving RDV drug powder using the mixture of DMSO: MeOH (30:70 v/v). The RDV working standard solutions for calibration and quality controls were prepared using methanol in concentrations of 100, 10, 1, 0.1, 0.01 µg/mL. 1, 2.5, 5, 7.5, 10, 25, 50, 75, 100, 250, 500, 1000, and 5000 ng/mL sample solutions were prepared freshly by spiking calibration standard solutions into the blank human plasma samples for method calibration. a) What type of calibration method is being described? Why do you think the authors chose this method as opposed to another? b) Based on the details provided in part a, describe an appropriate method blank…

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Chapter 14, Problem 14.18PAE

Interpretation Introduction

Interpretation:

The half-life of a radioisotope that decays to 12.5 % of its radioactivity in 12 years should be calculated.

Concept introduction:

The rate at which a radioactive sample decays is called an activity of a sample.

Half-life is the time required for one half of a sample to disintegrate.

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