Figuring out PEGylation
- Need to prepare 1/30 by volume solution of original particles
- Need to prepare 1/30 by volume solution of PEGylated particles
- Perform microrheology expt. in both solutions
- About 20ul of soln is used per expt. then a 2ul(part.)/58ul(H2O) seems ok
- Last time reconstituted 500ul of original particles in 200ul of water, but lost some particles in the process so it might be ok.
- For a check using microrheology of light scattering very small particles must be used. For 50nm you could see a difference between PEG and unmodified particles, for 500nm and up no.
- For 'big' particles a test based on the original reference must be used. I could obtain clear cut results using a way high saline solution (1M NaCl).