we are working on surface plasmon resonance sensors. As a part of the project, we somehow need to pattern on the gold film on which the reactions between the molecules (say peptides and antibody) will occur. we have to pattern the entire gold surface in such a way that different peptides when passed on the surface and then washed out it should bind at different regions on the film (suppose rectangular or square regions... analogous to the DMD pixels). So any idea how to make the pattern on the surface using the DMD device? we are using UV LED.and also can u suggest an effective way to choose the area of the small patterns(rectangular) so that the pattern does not vanish during the washing process. because of course, it should not be very small and also very large. I was wondering how to choose an effective area. one method I found that we can just use trial and error method, take a set of patterns varying from small rectangle to large ones, and then check for the smallest possible area in which the peptides remarkably remain attached.
Size: as long as it is larger than the plasmon propagation length it is Ok. For gold layer and red/NIR light it means sizes above 10-20µm. The optimal size can not determined upfront - it all depends on what is optimal for your measurement.
Washing away: covalently bound antibodies can not be easily washed away. If the antibody is easily washed away (e.g. was just physically adsorbed on the gold), it can be hardly used for biosensors. The baseline will always drift and this can be attributed to anything making such sensor unusable.
Now that you understand that you need a covalently bound antibody on the gold layer, you should answer what chemistry you are going to use for it. More importantly - what is the role of UV light in this procedure? There is a long story between projecting some image on the gold layer and antibodies deposited according to this image. It is not that easy or straightforward as you think. In practice one would use microstamping or inkjet printing/spotting for preparation of patterned sensors. Or whatever other technology that constrains spatially the chemical reaction.
- Badges
- Science method
- Similar topics
- Methodology
- Absorption Spectroscopy
- UV-Visible Spectroscopy