I have this doubt- When I inject a zero concentration or plain buffer! I get binding values of 5-10 RU in the active flow cell but the stability of that binding value in the active flow is <5 RU or negative.. If I look at 2-1 binding values for the same zero concentration I get 1-5 bidning RU and <3 stability RU values.
My question is can a zero buffer give any binding at all? if it does, are these RUs significant?
Let me know if you need any more information thanks
(PS: I use ready to use HBS-P buffer on a T100/200 instrument)
A perfect zero signal upon buffer injection is not often seen. Also, a small response of 5 - 10 RU is in most cases normal. The signal with buffer injection should be block shaped and the same in all channels. By subtracting for instance 2-1 you have the difference in chanel behaviour between 2 and 1. Ideally this will be close to zero.
The software on the T100/T200 will use this zero concentrations for double referencing.
Make sure you prepare the buffer injections and samples dilutions from the same running buffer and cap the vials.
A slight difference (1 mM NaCl) can result in 20 RU response!
Ref: Rich, R. L. and Myszka, D. G.Survey of the year 2000 commercial optical biosensor literature. J.Mol.Recognit.14: 273-294; (2001).