Dear Praveen, As said, Biacore3000 is not the best for small molecules, but in some case you can do nice things with this system. I see 3 possibilities : - You can immobilize your molecules on the chip if you have an amine on it which is supposed to not participate to the interaction. - You can have also the possibility to use carrier protein as BSA which is often found labeled with various small molecules and why not yours. - You can also use competition assays if your small molecules are supposed to inhibit larger molecules interaction.
I am agree with the problems of non stable baseline with NiNTA chips, covalent interactions are better, but in these cases regeneration can be more difficult... An other thing you can consider is streptavidin surfaces, especially if you can obtain your small molecules biotinylated. But in that case, long linkers should be used in case of your small molecules may be buried in an hydrophobic pocket. If you cannot fit in these case you should consider other experiments as ITC, NMR (STD transfert)... Good luck. Michel. > Le 31 mars 2017 à 07:01, Praveen Tripathi <tripathipraveen2...@gmail.com> a > écrit : > > Dear all, > Sorry for off-topic question. > I want to study protein interaction with few small molecules using SPR > (Machine- BIACORE 3000). > > The recombinant protein expressed in bacterial expression system is of 92 kDa > (with His tag), pI= 9. > > Question- > 1. What should be the chip of choice- NTA chip or CM5 chip of GE healthcare? > 2. Is there any alternative available for chips and machine? > > Thanks in advance. > > Regards > ---------------------------- > Praveen
