Mapping nanoparticles

Magnetic nanoparticulate material suitable for administration to a subject, the magnetic nanoparticulate material having bound to its surface:

• (a) copolymeric steric stabiliser that promotes dispersion of the magnetic nanoparticulate material in a liquid, wherein the copolymeric steric stabiliser comprises (i) an anchoring polymer segment having one or more binding groups that bind the copolymeric steric stabiliser to the magnetic nanoparticulate material, and (ii) a steric stabilising polymer segment that is different from the anchoring polymer segment, and
• (b) copolymeric mapping moiety comprising (i) an anchoring polymer segment having one or more binding groups that bind the copolymeric mapping moiety to the magnetic nanoparticulate material, (ii) one or more mapping groups comprising an agent that specifically binds to fibroblast activation protein (FAP), and (iii) a coupling polymer segment that is different to the anchoring polymer segment of the copolymeric mapping moiety, wherein the coupling polymer segment couples the anchoring polymer segment to the one or more mapping groups;
• wherein the coupling polymer segment comprises polymer selected from polyacrylamide, polyvinyl alcohol, polyalkylene oxide, polyoxamers, polyhydroxyethylacrylate, poly-N-isopropylacrylamide, polydimethylamino-ethylmethacrylate, polyvinyl pyrrolidone, polyacrylicacid, polymethacrylamide, poly vinyl ester, poly vinyl amide, polysulfonated divinylbenzene, poly-L-lysine, polyaspartate, poly lactic acid, polyethyleneimine, polyalkylcyanoacrylate, polymaleic anhydride, polymaleic acid and a copolymer of two or more of said polymers;
• and
• wherein the steric stabilising polymer segment comprises a polyacrylamide-co-polyalkylene oxide block copolymer that has about 8 to about 60 polymerised acrylamide units and about 2 to about 10 polymerised alkylene oxide units.