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OD A260/A280 ratio to check oligo quality

Can I use A260/A280 ratio to check my oligo quality?

Oligonucleotide quality check using A260/A280 ratio is not an accurate measurement, as it dependent on the base composition. Table below is an example of A260/A280 ratio for a 20 mer crude oligonucleotide with different compositions and result of A260/A280 ratio show it has less than 1.8 which due to the factors below.

Base composition A260/A280
100% A 2.50
100% T 1.14
100% C 1.15
100% G 1.85
25% of each base 1.66