All of our modification data is at room temperature. While modification at 4 degrees may work, we cannot guarantee success. For the modification, we would suggest 15 equiv at 2 mg/mL protein A concentration. We suggest 10 equiv at 2 mg/mL. For the conjugations, we recommend a 1/1 mol/mol ratio. However, we suggest trying 1/1.5 and 1/2 antibody/protein A ratios on an initial small scale (~10 µg) reactions that can be analyzed by PAGE. Use 10X TurboLink buffer in the solution to optimize the conjugation reaction.