Hi everyone, I hope you have a wonderful summer now! We have met in Belfast before, you guys are so nice and glad to meet all of you. Two months has past in a flash. I have settled down in Sweden and finally completed various formalities in life. Though I’m tired, it is a fruitful time and make me get in touch with many new knowledge, experiences and friendly people.
In this blog, I would like to update some recent project progresses so as to make my first blog more scientific. Since one important thing of my project is to develop a low cost advanced reusable compact iSPR optical system which can be easily attached to the smartphone, after several improvements of the design, we have obtained one which can observe the SPR signal stably and completely so far. Hence the next step is the verification. Botulinum neurotoxin A ((BoNT/A) testing is introduced in this case. Botulinum neurotoxins (BoNTs) are the most potent biological toxin known and Botulinum neurotoxin A (BoNT/A) is the most potent of them.
To be honest, this is my first time to handle such an immunoassay. All this is very novel for me. Thank you so much for Anke helping me a lot for preparing and running this assay. Generally, there are two steps: immobilisation (also called surface functionalisation, is used to immobilise ligand) and interaction analysis (basically, it is the interaction between the analyte in running buffer and the immobilised ligand on the surface).
As for the immobilisation, firstly, the mixture of 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS) is pumped through the chip surface to activate it. Then inject the diluted antibody (monoclonal Botulinum AB) with immobilisation buffer, the antibody can be attached to the dextran matrix on the surface. After that, inject deactivate solution to deactivate excess reactive groups and remove non attached antibody. A prepared surface is obtained for the analyte binding activity.
During interaction analysis, the diluted analyte is injected at a stable flow rate and then the regeneration solution is injected in order to remove the analyte from the attached ligand without destroying its activity and repeat this procedures several times with different analyte concentrations.
Besides that, adding one step of injecting the enhancement antibody between injecting analyte and injecting regeneration solution is to detect the limitation of this system. Commonly, the most diluted analyte solution is applied for this procedure.
Now I am on my summer vacation with my family, we are going to travel a bit around northern Europe. Hopefully when I come back and finish the assay, I can get some positive and promising results.
Wish you all have a great and warm summer again.)
Thank you kindly for your reading.
Tran, H., & Liu, C. Q. (2012). Label-free detection of botulinum neurotoxins using a surface plasmon resonance biosensor. Advances in Immunoassay Technology, 109.
Arnon, S. S., Schechter, R., Inglesby, T. V., Henderson, D. A., Bartlett, J. G., Ascher, M. S., Eitzen, E., Fine, A. D., Hauer, J., Layton, M., Lillibridge, S., Osterholm, M. T., O’Toole, T., Parker, G., Perl, T. M., Russell, P. K., Swerdlow, D. L. & Tonat, K. (2001). Botulinum toxin as a biological weapon: medical and public health management. Jama, 285(8), 1059-70.