An analyst needs to evaluate the potential effect of an interferent, I, on the quantitative analysis for an analyte, A. She begins by measuring the signal for a sample in which the interferent is absent and the analyte is present with a concentration of 15 ppm, obtaining an average signal of 23.3 (arbitrary units). When analyzing a sample in which the analyte is absent and the interferent is present with a concentration of 25 ppm, she obtains an average signal of 13.7. What is the sensitivity for the analyte? What is the sensitivity for the interfering? What is the value of the selectivity coefficient?

The students conducted the assay for LDH activity using the two serum samples. Each cuvette (path length 1 cm) contained 3ml of a suitable assay buffer (including pyruvate as substrate). 20 microlitres of either serum was added to the cuvette and the absorbance values immediately recorded at the optimum wavelength for a period of 5 minutes (absorbance readings taken every 30 seconds).   Protein concentration of serum sample (mg/ml) Change in absorbance at optimum wavelength per minute Control serum (C) 8 -0.04 Diseased serum (D) 7.8 -0.6 1c. Using the molar absorption coefficient of NADH as 6220 M-1 cm-1, and by application of the Beer-Lambert law, estimate the enzyme activity in the two samples (C and D). Express activity as moles per second.  1d. Estimate the specific activity of the two samples (moles per second per microgram).

The Beer’s Law plot of the standard curve for the equilibrium experiment was determined by plotting?   absorbance versus [Fe3+]   absorbance versus % transmittance   % transmittance versus [FeSCN2+]   absorbance versus [FeSCN2+]

OA B. OC D. CE. Compound G is an Aldehyde Compound H is a Carboxylic acid Compound is an alcohol A Compound B is a ketone Compound is an Adehyde A Compound B is a Ketone B Compound B is an Aldehyde Compound is a Ketone Compound is an Alcohol Compound B is a Carboxylic acid