Well, I can try and explain the inorganic part of the situation.

After doing a bit of research on your webpage, and on the structure of the polysaccharides you are using, I believe your observations are due to coordination compounds between the transition metal and the polysaccharides. The nitrogen (and some Oxygen atoms) in glycosaminoglycans have a lone pair, and through a lewis acid/base reaction, can form a complex with the unoccupied D orbitals of the metal cation. The complex will have significantly different spectral properties from the bare cation, and will also exhibit different reactive properties.

You may want to go to the chemistry library and check out a book on inorganic chemistry. It will probably answer many of your questions.

How big is your polysaccharide? Are they big enough to fold? What's the siggested size of the "nano particles"? Yiou know, polysacharide alone could be defined as a nano-particle. You should get a book on photochemistry.