I use Bionavi210A SPR. I'm still learning. I try to immobilze HSA with amino coupling on CMD (=CM5) chip. But my protein signal is very low. My coupling buffer is 10 mM Na Acetate pH: 5.2. HSA is globulin and fatty acid free. I tried a lot of different chemical such as different protein (BSA), different EDC and NHS, Different buffer ( 5 mM MES pH: 5.0) but nothing changes. I also tried different concentraion of proteins. I sent you my sensogram results.
I sent you my sensogram results for BSA and HSA .
Do you have any recommadation to solve this problem?
Low protein signal during immobilisation
23 Aug 2014 17:08 #2
Not sure what i see in your sensorgrams (immobilization or experiment; please explain) but i have some suggestions.
- take a fresh equilibrated sensor chip
- inject the HSA solution in different pH buffers (www.sprpages.nl/immobilization/ligand-pre-concentration.html)
- take the pH solution with the "best" pre concentration properties.
- then make fresh NHS and EDC according to the Biacore protocol or by the provided BioNavis protocol.
- Try again.