1. What is DNA Copy Number Calculation?

The DNA copy number calculation determines the number of copies of a specific DNA fragment per microliter based on its concentration and length. This is essential for molecular biology applications like PCR, sequencing, and cloning.

2. How Does the Calculator Work?

The calculator uses the following equation:

Where:

• \( CN \) — Copy number (copies/μL)
• \( C \) — DNA concentration (ng/μL)
• \( L \) — DNA length (base pairs)
• 660 — Average molecular weight of one DNA base pair (g/mol)
• 6.022 × 10²³ — Avogadro's number (molecules/mol)

Explanation: The equation converts mass concentration to molar concentration, then to molecule count using Avogadro's number.

3. Importance of Copy Number Calculation

Details: Knowing DNA copy number is crucial for accurate quantification in experiments like qPCR, ensuring proper template amounts for amplification, and standardizing molecular biology protocols.

4. Using the Calculator

Tips: Enter DNA concentration in ng/μL and length in base pairs. For best results, use accurate measurements from fluorometric or spectrophotometric methods.

5. Frequently Asked Questions (FAQ)

Q1: Why is 660 used in the formula?
A: 660 g/mol is the average molecular weight of one DNA base pair (dNTP), accounting for the phosphate backbone and nucleotide variations.

Q2: Does this work for single-stranded DNA?
A: No, this formula is specifically for double-stranded DNA. For ssDNA, remove the multiplication by 2 in the denominator.

Q3: What concentration range works best?
A: The formula works for any concentration, but typical working concentrations range from 0.1 ng/μL to 1000 ng/μL.

Q4: How accurate is this calculation?
A: Accuracy depends on the precision of your concentration measurement and knowing the exact fragment length.

Q5: Can I use this for RNA?
A: No, RNA calculations use different molecular weights. For RNA, use 340 g/mol as the average weight per nucleotide.