1. What is DNA Concentration?

DNA concentration measurement is essential in molecular biology to determine the amount of DNA in a solution. The A260 reading from a spectrophotometer is commonly used to estimate DNA concentration, especially for kids' DNA samples.

2. How Does the Calculator Work?

The calculator uses the simple DNA concentration formula:

Where:

• \( Conc \) — DNA concentration (ng/µL)
• \( A260 \) — Absorbance reading at 260nm (dimensionless)
• 50 — Conversion factor for double-stranded DNA (ng/µL per 1 A260 unit)

Explanation: DNA absorbs UV light at 260nm, and this absorbance is proportional to its concentration in solution.

3. Importance of DNA Concentration

Details: Accurate DNA concentration measurement is crucial for experiments like PCR, sequencing, and cloning where precise DNA amounts are required.

4. Using the Calculator

Tips: Simply enter the A260 reading from your spectrophotometer. The value must be positive and typically ranges from 0.001 to 2.0 for accurate measurements.

5. Frequently Asked Questions (FAQ)

Q1: Why multiply by 50?
A: For double-stranded DNA, 1 A260 unit equals approximately 50 ng/µL of DNA.

Q2: Is this calculator suitable for RNA?
A: No, RNA calculations use a different conversion factor (40 ng/µL per A260 unit).

Q3: What's a good A260 reading range?
A: Ideally between 0.1 and 1.0 for most accurate measurements. Values outside this range may need dilution or concentration.

Q4: Why is this called "for kids"?
A: This simplified version is designed for educational purposes and introductory molecular biology work.

Q5: How should I prepare my sample for measurement?
A: Use a clean cuvette, blank with your buffer solution, and ensure the sample is free of contaminants that absorb at 260nm.