Final answer:
To preserve chromogenic Western blot results, take photographs or scans after the chromogenic substrate develops color on the membrane, providing a permanent visual record.
Step-by-step explanation:
To make a permanent replica of chromogenic Western blot results, you must first transfer the separated proteins from a polyacrylamide gel to a nitrocellulose membrane where they are immobilized. Using antibodies, the specific proteins can be targeted and a chromogenic substrate is added, which develops color where the secondary antibodies are bound. To create a permanent record, the membrane may be photographed or scanned to capture the developed color, thus preserving the data. A similar process applies to other blotting techniques like Southern blot, which uses DNA, or Northern blot, which uses RNA. These techniques also involve transferring the molecules to a membrane and hybridizing them with a labeled probe that can be visualized on an X-ray film to create an autoradiograph, which serves as a permanent record of the experiment.