| | Re: Signal loss from blot
some manufacturers may have interfering salts, buffers or even residual proteinases / chemicals in their reagents that may interfere or degrade the quality of proteins and their detection.
We have noticed the same thing with different buffers, antibodies, and blots as you have.
Of note you mention Phosho-blots and unfortunately that may be the key issue to your failure to detect the proteins with blotting at a later stage.
Phosphorylation is notoriously difficult to detect even with fresh antibody, protein and blots. The issue is phosphorylation is a modification which is easily modified by many phosphrylation enzymes, for example removed by phosphatase, and lost.
Were you always able to reblot phospho-protein blots (ie blotting for signalling detection) after storage or was it just protein detection?