To determine the expected absorbance of a solution of DNA at a concentration of 34.00 ng/μL, we can use the absorbance formula based on the Beer-Lambert Law.
The absorbance (A) can be calculated using the following formula:
\[ A = \epsilon \cdot c \cdot l \]
Where:
- \( A \) = Absorbance
- \( \epsilon \) = Molar absorptivity (L/(mol·cm))
- \( c \) = Concentration (mol/L)
- \( l \) = Path length (cm)
For nucleic acids, a common value for the molar absorptivity (\( \epsilon \)) at 260 nm is approximately 0.020 (optical density per ng/μL).
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Convert the concentration from ng/μL to μg/mL:
- 34.00 ng/μL = 34.00 μg/mL
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Use the typical conversion that 1 μg/mL of DNA corresponds to an absorbance of approximately 0.020 at 260 nm. Thus: \[ A = \text{Concentration (μg/mL)} \times 0.020 \]
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Substitute the given concentration: \[ A = 34.00 , \text{μg/mL} \times 0.020 = 0.68 \]
Thus, the expected absorbance of the solution is 0.68.