To restore the binding capacity of you antibody, you need to first identify the root causes of the antibody for losing it binding capacity. If your antibody loses its binding affinity because of aggregation, its binding capacity may be probably restored by denaturing the aggregates followed by refolding of the Abs into its native state. You can get numbers of protein refolding formulations from literature.

However, if your antibody is degraded or undergone chemical instability, it may be difficult to restore its binding capacity.

thank you Alemu, I think it is not degraded because it was work efficiently and then frozen, so the probability of getting degraded is almost excluded it is recommended to be aggregated

I think you should exclude other causes for the low signals. Blaming the atibody is reasonable, but not the only possibility. Most antibodies can be frozen without severe consequences.

Although refolding of antibodies is theoretically possible and performed in the case of recombinant antibody fragments from certain expression systems, using it to restore the properties of an analytical reagent s not a common practice. Refolding is always partial, and after denaturation/refolding the activity can be even lower.I would suggest to play with the experimental conditions (for intance, increasing Ab concentrations) to compensate the loss of inding activity if the damage has really occurred. Buying a new batch of antibody is the only way to solve the problem at 100%.

Thanks Gertrudis, Off course I did many combinations as increasing concentration and so on, but no way. I will buy a new antibody, thanks