im currently working on targeted drug delivery , where im going to use antibodies and liposomes after mixing them , all i wanted to know is how can i observe that either antibodies and liposomes are bound together or not?
You could check if the size (nm) of you liposomes changes. Adding protein to the liposome also changed the zeta-potential (mV). Or you could check if your conjugated liposomes bind to the antigen and control liposomes don't.
Messerschmidt, S. K., A. Kolbe, D. Muller, M. Knoll, J. Pleiss and R. E. Kontermann (2008). "Novel single-chain Fv' formats for the generation of immunoliposomes by site-directed coupling." Bioconjug Chem 19(1): 362-369.
As suggested previously, you would first have to separate the unbound antibodies from the liposomes by dialysis. I would then set up a simple lateral-flow assay in which the strip has the antigen deposited as a test line. The liposomes, containing a suitable visible dye, would then be allowed to flow along the strip. If the liposomes bind to the antigen line, the attachment of the antibodies to the liposomes would be confirmed. A more positive way to ensure antibody-liposome attachment would be to include a coupling agent into the liposome bilayer. A large number of procedures for doing this can be found in the literature.