1. What is DNA Molarity?

DNA molarity refers to the concentration of DNA molecules in solution, expressed in micromolar (μM) units. It's essential for molecular biology experiments where precise DNA amounts are required.

2. How Does the Calculator Work?

The calculator uses the DNA molarity equation:

Where:

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

Explanation: The equation converts mass concentration (ng/μL) to molar concentration (μM) by accounting for the molecular weight of the DNA.

3. Importance of DNA Molarity Calculation

Details: Accurate molarity calculation is crucial for PCR, sequencing, cloning, and other molecular biology techniques where precise DNA amounts affect experimental outcomes.

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 (number of base pairs × 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 comparison between different DNA fragments.

Q3: What's a typical molarity range for PCR?
A: Most PCR reactions use 0.1-1 μM of each primer and 0.01-0.1 μM of template DNA.

Q4: Does this work for RNA as well?
A: Yes, but use RNA molecular weights (340 g/mol per nucleotide for ssRNA).

Q5: How accurate is this calculation?
A: Very accurate if concentration and MW are measured precisely. Spectrophotometer errors are typically the limiting factor.