1. What is Oligonucleotide Molecular Weight?

The molecular weight of an oligonucleotide (or peptide) is the sum of the molecular weights of its constituent amino acids. This calculator provides an estimate based on the amino acid sequence.

2. How Does the Calculator Work?

The calculator uses the following formula:

Where:

• \( MW \) — Total molecular weight (g/mol)
• \( MW_{aa} \) — Molecular weight of each amino acid (g/mol)

Explanation: The calculator sums the standard molecular weights of each amino acid in the sequence.

3. Importance of Molecular Weight Calculation

Details: Knowing the molecular weight is essential for experimental design, concentration calculations, and stoichiometric measurements in biochemical research.

4. Using the Calculator

Tips: Enter the amino acid sequence using single-letter codes (e.g., "ACDE"). The sequence should only contain standard amino acid codes (A, R, N, D, C, Q, E, G, H, I, L, K, M, F, P, S, T, W, Y, V).

5. Frequently Asked Questions (FAQ)

Q1: Does this calculator account for modifications?
A: No, this calculates only the base molecular weight of standard amino acids without any modifications.

Q2: What about terminal groups?
A: This calculation doesn't include the weight of terminal groups (NH2- and -COOH) or any post-translational modifications.

Q3: How accurate is this calculation?
A: It provides a theoretical molecular weight based on standard amino acid weights. Actual experimental values may vary slightly.

Q4: Can I use lowercase letters?
A: Yes, the calculator will convert lowercase letters to uppercase automatically.

Q5: What about non-standard amino acids?
A: This calculator only recognizes the 20 standard amino acids. Non-standard amino acids will trigger an error.