Question

If your upper limit of linearity is 200 ng/mL, describe what you must do with a specimens yielding a value of 921 ng/mL. The test requires a 150 uL of specimen.

Answer 1

To get the value within the upper linearity range we would have to dilute the specimen sample solution.

Required volume = 150 ul = 0.150 ml

Available specimen = 921 ng/ml

upper limit = 200 ng/ml

using, C1V1 = C2V2

with, C1V1 be concentration x volume of original specimen solution available

C2V2 be concentration x volume of final required speciment solution

we get,

Volume of original speciment solution required = 200 x 0.150/921 = 0.0326 ml = 32.6 ul

So we would take 32.6 ul of 921 ng/ml solution and dilute to 150 ul total volume for analysis.