A plasma reaction converts A (Molecular weight = 200) to B and uses NAD as a co-substrate and produces NADH as a by product (1 mole of NADH is produced per every 1 mole of A converted to B). The amount of NADH can be determined by monitoring its’ absorbance at 340nm in a spectrophotometer.
1ml of plasma is taken and diluted with 4 ml of reaction buffer with the enzyme required to convert A to B inhibited. 1ml of this sample is added to a cuvette and the inhibition is then stopped by adding 2 ml of a “inhibition prevention” buffer and the natural conversion of A to B allowed to occur. This conversion is completed in 10 minutes after which time the change in absorbance at 340nm is recorded.
The change in absorbance is 0.82 absorbance units over the 10 minutes. The molar extinction coefficient of NADH at 340nm is 6220.
What is the concentration of compound A in ng/100mL?
Well, I can certainly calculate that for you, but let's mix some humor into this science equation, shall we? Here we go:
To find the concentration of compound A in ng/100mL, we first need to understand a few things. NADH, the byproduct, is like the sidekick that's always with Compound A. They go around causing reactions and having a spectrophotometer party together.
Now, they measure NADH's absorbance at 340nm to determine how much of it is present. It's like seeing how many party hats are flying around in the air.
So, we have a change in absorbance of 0.82 absorbance units over 10 minutes. That's like saying, "Hey, the number of party hats flying around has increased by 0.82!"
The molar extinction coefficient of NADH at 340nm is 6220. That means if we had one mole of NADH, we would have 6220 party hats flying around! Talk about a lively party.
Now, to calculate the concentration of Compound A, we need to convert these absorbance units and molar extinction coefficient into real numbers. Remember, we diluted the plasma sample, so we need to take that into account too.
So, let's crunch some numbers: 0.82 absorbance units multiplied by 6220 (the molar extinction coefficient) gives us approximately 5092.4 ng/mL of NADH.
But hold your party hats! The sample was diluted with 4 mL of reaction buffer, so we need to divide that number by 4, giving us 1273.1 ng/mL of NADH in the diluted sample.
Since we know that 1 mL of the diluted sample contains 1/5th of the original plasma sample, we multiply 1273.1 by 5, giving us 6365.5 ng/mL of NADH in the original plasma sample.
But remember, Compound A and NADH go together like peanut butter and jelly. So, for every mole of Compound A, we have one mole of NADH. That's a tight bond.
Now, let's convert ng/mL to ng/100mL by multiplying 6365.5 by 100, which gives us 636,550 ng/100mL of NADH in the original plasma sample.
Since we have a 1:1 ratio between Compound A and NADH, the concentration of Compound A is also 636,550 ng/100mL.
So there you have it! The concentration of compound A in ng/100mL is approximately 636,550 ng/100mL. Just imagine that many party hats floating around in your plasma! Where's the confetti?
To find the concentration of compound A, we need to use the Beer-Lambert Law equation, which relates absorbance (A), molar extinction coefficient (ε), concentration (C), and path length (l).
The equation is:
A = ε * C * l
In this case, the change in absorbance over the 10 minutes is given as 0.82 absorbance units, the molar extinction coefficient of NADH at 340nm is 6220, and the path length is not specified.
However, we can assume a standard path length of 1 cm, which is commonly used in spectrophotometry.
Using the given values, we can rearrange the equation to solve for the concentration (C) of A:
C = A / (ε * l)
Since the concentration will be in molar units, we also need to convert it to ng/100mL. We can do this by multiplying by the molecular weight of A and converting the units.
Let's calculate the concentration:
C = 0.82 / (6220 * 1)
Now, let's calculate the concentration of compound A:
C = 0.82 / 6220 = 0.00013198 M
To convert from molar to ng/100mL, we need to multiply by the molecular weight and convert the units.
The molecular weight of compound A is given as 200 g/mol:
C_ng/100mL = C * (200 g/mol) * (1000 ng/g) * (100 mL)
C_ng/100mL = 0.00013198 * 200 * 1000 * 100 = 263.96 ng/100mL
Therefore, the concentration of compound A is approximately 263.96 ng/100mL.
To determine the concentration of compound A in ng/100mL, we first need to calculate the amount of NADH produced during the reaction.
Given:
Change in absorbance = 0.82 absorbance units
Molar extinction coefficient of NADH at 340nm = 6220
The change in absorbance is directly proportional to the concentration of NADH. We can use the Beer-Lambert Law to calculate the concentration of NADH.
Beer-Lambert Law:
Absorbance = molar extinction coefficient * path length * concentration
Since we are given the change in absorbance and the molar extinction coefficient, we can rearrange the equation to solve for the concentration:
Concentration = change in absorbance / (molar extinction coefficient * path length)
The path length is the thickness of the cuvette, which is commonly 1 cm.
Concentration of NADH = 0.82 / (6220 * 1 cm) [Substituting the given values]
Now, since the reaction produces 1 mole of NADH for every 1 mole of A converted to B, the concentration of NADH is also equal to the concentration of compound A.
Therefore, the concentration of compound A = 0.82 / (6220 * 1 cm) ng/mL.
But we need the concentration in ng/100mL, so we need to convert mL to 100mL:
Concentration of compound A = (0.82 / (6220 * 1 cm)) * (100 mL / 1 mL)
Simplifying further:
Concentration of compound A = (0.82 / 6220) * 1000 ng/100mL
Therefore, the concentration of compound A is (0.82 / 6220) * 1000 ng/100mL.
A = kc
A = 0.82
k = 6220.
Solve for c in mols/L.
Correct for the two dilutions; i.e., 1 up to 3 and 1 up to 5 and the answer is in mols/L. Convert that to ng/L, then to ng/100 mL.