Convert between mass and moles for ssDNA and dsDNA sequences
dsDNA (average): MW = (length × 617.96) + 36.04 g/mol
ssDNA (average): MW = (length × 308.97) + 18.02 g/mol
Exact (sequence): A=313.21, T=304.20, C=289.18, G=329.21 g/mol
Copy number: moles × 6.022 × 10²³