1. What is DNA Molarity Calculation?

The DNA molarity calculation converts the mass concentration of DNA (ng/μL) to molar concentration (μM), which is essential for many molecular biology applications like PCR, sequencing, and cloning.

2. How Does the Calculator Work?

The calculator uses the DNA molarity formula:

Where:

• \( M \) — Molarity (μM)
• \( C \) — DNA concentration (ng/μL)
• \( MW \) — Molecular weight (g/mol)

Explanation: The formula converts nanograms per microliter to micromolar by accounting for the molecular weight of the DNA and appropriate unit conversions.

3. Importance of DNA Molarity

Details: Knowing the molar concentration of DNA is crucial for experiments requiring precise amounts of DNA molecules, such as setting up reactions with specific DNA:primer ratios or preparing sequencing libraries.

4. Using the Calculator

Tips: Enter DNA concentration in ng/μL and molecular weight in g/mol. For double-stranded DNA, MW can be calculated as (length in bp × 607.4) + 157.9.

5. Frequently Asked Questions (FAQ)

Q1: How do I determine the molecular weight of my DNA?
A: For dsDNA: MW = (length in bp × 607.4) + 157.9. For ssDNA: MW = (length in nt × 303.7) + 79.0.

Q2: Why convert to molarity instead of using ng/μL?
A: Molarity accounts for molecule size, allowing accurate stoichiometric calculations between different DNA molecules.

Q3: What's a typical DNA concentration for PCR?
A: Most PCR reactions use template DNA at 0.1-1 μM final concentration, depending on the application.

Q4: Does this work for RNA as well?
A: Yes, but use RNA-specific molecular weight: MW = (length in nt × 320.5) + 159.0.

Q5: How accurate is this calculation?
A: Very accurate if you have precise concentration measurements and correct molecular weight. Nanodrop measurements may have ±10% error.