1. What is DNA Molarity Calculation?

The DNA molarity calculation converts mass concentration (ng/μL) to molar concentration (μM), which is essential for many molecular biology applications where the number of molecules is more important than their mass.

2. How Does the Calculator Work?

The calculator uses the following equation:

Where:

• \( M \) — Molarity in micromolar (μM)
• \( C \) — DNA concentration in nanograms per microliter (ng/μL)
• \( MW \) — Molecular weight in grams per mole (g/mol)

Explanation: The equation converts mass concentration to molar concentration by dividing by the molecular weight and scaling appropriately.

3. Importance of DNA Concentration

Details: Accurate molarity calculations are crucial for PCR, sequencing, cloning, and other molecular biology techniques where precise amounts of DNA are required.

4. Using the Calculator

Tips: Enter DNA concentration in ng/μL and molecular weight in g/mol. For double-stranded DNA, use 660 g/mol per base pair as a general estimate.

5. Frequently Asked Questions (FAQ)

Q1: How do I determine molecular weight?
A: For DNA, MW = (number of bases × 330 g/mol) - 61 g/mol for single-stranded DNA, or (number of base pairs × 660 g/mol) for double-stranded DNA.

Q2: Why convert to molarity?
A: Molarity allows you to know exactly how many molecules are present, which is important for stoichiometric reactions.

Q3: What's a typical DNA concentration range?
A: Purified DNA samples typically range from 10-500 ng/μL, but this varies by extraction method and sample type.

Q4: Does this work for RNA too?
A: Yes, but use RNA's molecular weight (340 g/mol per nucleotide) instead of DNA's.

Q5: What if my DNA is single-stranded?
A: Use the single-stranded molecular weight (330 g/mol per nucleotide) in your calculation.