A 20mM solution of dopamine is diluted 1 in 8. The diluted dopamine solution was used for a tyrosinase assay that had a total volume of 1.5mL. 20μL of tyrosinase was used for the assay. The reaction was followed spectrophotometrically and a progress curve plotted from the spectrophotometric data. Using the progress curve, the initial velocity was calculated as 0.30 ΔA/min.
The assay was repeated as above, with a different volume of tyrosinase. The initial velocity was 0.01 ΔA/s. What volume (in μL) of tyrosinase was used for the assay?
The assay was repeated as above, with a different volume of tyrosinase. The initial velocity was 0.01 ΔA/s. What volume (in μL) of tyrosinase was used for the assay?
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total volume = 1.5ml - 20µL enzyme = 1.48ml for dopamine and water
20mM x V1 = 2.5mM x 1.5ml.....V1 = 0.188ml domamine used
20µL enzyme
180µL dopamine
1.3ml water
rate = 0.3∆A/min = 0.005∆A/s
xµl enzyme
180µL dopamine
water
rate = 0.01∆A/s
rate doubles so enzyme concentration doubled, 40µl
20mM x V1 = 2.5mM x 1.5ml.....V1 = 0.188ml domamine used
20µL enzyme
180µL dopamine
1.3ml water
rate = 0.3∆A/min = 0.005∆A/s
xµl enzyme
180µL dopamine
water
rate = 0.01∆A/s
rate doubles so enzyme concentration doubled, 40µl