1. What is DNA Molar Concentration?

DNA molar concentration refers to the number of moles of DNA per liter of solution (μM). It's essential for molecular biology applications like PCR, sequencing, and cloning where precise DNA amounts are required.

2. How Does the Calculator Work?

The calculator uses the DNA molar concentration formula:

Where:

• \( M \) — Molar concentration (μM)
• \( C \) — DNA concentration (μg/mL)
• \( L \) — DNA length (base pairs)
• \( 660 \) — Average molecular weight of a DNA base pair (g/mol)

Explanation: The formula converts mass concentration to molar concentration by accounting for the molecular weight of the DNA based on its length.

3. Importance of DNA Molarity

Details: Knowing the molar concentration is crucial for experiments requiring specific DNA copy numbers, such as setting up PCR reactions with known template amounts or preparing sequencing libraries.

4. Using the Calculator

Tips: Enter DNA concentration in μg/mL and length in base pairs. Both values must be positive numbers. The calculator will output the molar concentration in μM (micromolar).

5. Frequently Asked Questions (FAQ)

Q1: Why use 660 g/mol as the average molecular weight?
A: This is the average molecular weight of one DNA base pair (including both nucleotides and counterions).

Q2: Does this work for single-stranded DNA?
A: No, for single-stranded DNA you should use 330 g/mol as the average molecular weight per nucleotide.

Q3: What's a typical molar concentration for PCR?
A: Typical template concentrations range from 0.1-10 μM depending on the application and PCR type.

Q4: How does DNA length affect molarity?
A: Longer DNA molecules at the same mass concentration will have lower molar concentrations because each molecule weighs more.

Q5: Can I use this for RNA calculations?
A: No, RNA has a different average molecular weight (about 340 g/mol per nucleotide).