Runcell posts tagged “molarity”
A280 Protein Concentration Tutorial: ε280 for 11 Proteins, and Why A280 ≠ mg/mL
Computed ε280, molecular weight and Abs 0.1% for 11 common lab proteins from UniProt mature chains. Shows how far the '1 A280 = 1 mg/mL' shortcut is off (0.17× to 2.65×), what pasting the precursor sequence costs, and why nucleic-acid contamination skews proteins with a low Abs 0.1% the most.Read More →
DNA Molecular Weight in Python: A Runnable ng/µL → nM Workflow
Why ng/µL → nM calculators disagree by 7%, measured on real NCBI sequences with Biopython. Covers free acid vs sodium salt, the 650/660/330 rules of thumb, 5' phosphates, and a full pUC19 digest-to-ligation workflow.Read More →