Immunofluorescent analysis of PSD-95 (green) and MAP2 (red) on rat primary cortical neurons cultured for 28 days in the B-27 Plus Neuronal Culture System (Product # A3653401). At day 28 the cells were fixed with 4% paraformaldehyde for 15 min, permeabilized with 0.1% triton X-100 for 30min, and blocked with 1% BSA for 30 min at room temperature. Cells were stained with anti-PSD95 antibody (Product # 51-6900) at a dilution of 1:200, and anti-MAP2 (Product # 13-1500) at a dilution of 1:400, in 1% BSA staining buffer, overnight at 4C, and then incubated with Alexa Fluor 488 conjugated donkey anti-rabbit (Product # A-21206) and Alexa Fluor 594 donkey anti-mouse (Product # A-21203) antibodies at a dilution of 1:1000 for 30 min. at room temp. Wash 3 times with DPBS. Stain with DAPI for nucleus.