Re: [ccp4bb] off topic question BIAcore problem

PM To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] off topic question BIAcore problem Thanks a lot for the kind reply. I used CM5 chip at pH 7.4. I am not quite sure about the PI of my protein but I have different truncations of my protein which behaved similarly. I can fit my data quite good

Re: [ccp4bb] off topic question BIAcore problem

Well that looks pretty real then. You might have wrong concentrations in one or the other experiment perhaps hence the difference. Jürgen On Feb 20, 2013, at 5:45 PM, xianchi dong wrote: Thanks a lot for the kind reply. I used CM5 chip at pH 7.4. I am not quite sure about the PI of my protein

Re: [ccp4bb] off topic question BIAcore problem

Thanks a lot for the kind reply. I used CM5 chip at pH 7.4. I am not quite sure about the PI of my protein but I have different truncations of my protein which behaved similarly. I can fit my data quite good with the Chi2 around 1 and Rmax 150. The kon is about 10e4 and the KD is around 0.2 nM. Th

Re: [ccp4bb] off topic question BIAcore problem

ent means. HTH, Zhijie From: xianchi dong Sent: Wednesday, February 20, 2013 12:03 PM To: CCP4BB@JISCMAIL.AC.UK Subject: [ccp4bb] off topic question BIAcore problem Dear all, Recently I have measure a set of kinetic data of a receptor ligand interaction using BIAcore 3000. To my surpr

Re: [ccp4bb] off topic question BIAcore problem

Dear Xianchi, unfortunately, dissociation rate constant kd 10^-6 s^-1 was just beyond the limit of Biacore in 1999 (e.g. see Fig. 1 in http://www.ncbi.nlm.nih.gov/pubmed/10556876). I am not sure about these days. As Juergen noted, you may have a problem with rebinding (you could try to reduce amoun

Re: [ccp4bb] off topic question BIAcore problem

I assume you use CM5 chips ? I further assume you run at pH 7.5 perhaps ? What's the pI of your analyte ? > 7.5 ? Do you get significant binding to your reference cell under the conditions you are running ? You might get rebinding to your negatively charged surface and the dissociation you are m

[ccp4bb] off topic question BIAcore problem

Dear all, Recently I have measure a set of kinetic data of a receptor ligand interaction using BIAcore 3000. To my surprise, the dissociation rate is very low (~ 10e-6). During the measurement, I use a long dissociation time (2 hours) .I repeat several time which give very similar results. So I am