小中大
1. 200ug protein is too much to seperate
2. 2h's blocking is too long, try 1h
3. try nitrocellulose membrane if i were you
4. don't forget to add protease and phosphatase inhibitor
5. try high concentration of primary antibody. We bought several antibodies from AbCam, sometimes Ab works when reaches to 1:100- 1:200 dilution.
Good luck