Purification and quantification
Free dye raises absorbance and background. Separate it from the conjugate before measuring target concentration and degree of labeling (DOL), and check for precipitation or aggregation. Use the dye-specific extinction coefficient and absorbance correction together with target-specific concentration parameters.
Function and storage
Compare at matched target concentration: specific binding and negative-sample background for antibodies, activity for enzymes, and hybridization or intended function for nucleic acids. Recheck signal, aggregation and function under the same settings after storage. Set conjugate storage conditions for the target and formulation.
Keep comparison conditions matched
Match target concentration rather than total protein concentration. With additives such as BSA, total protein does not represent target recovery. Report DOL, target recovery, positive and negative signals and detection settings to guide input or purification changes.