# The working curve for the determination of dopamine at a nanoneedle electrode by differential-pulse.

The working curve for the determination of dopamine at a

nanoneedle electrode by differential-pulse voltammetry (Figure 25-38) was

constructed from the following table of data.

(a) Use Excel to perform a least-squares analysis of the

data to determine the slope, intercept, and regression statistics, including

the standard deviation about regression.

(b) Use your results to find the concentration of dopamine

in a sample solution that produced a peak current of 2.92 nA. This value is the

average of duplicate experiments.

(c) Calculate the standard deviation of the unknown

concentration and its 95% confidence interval assuming that each of the data in

the table was obtained in a single experiment.