Biomaterial coated gold nanostructures for photoacoustic imaging and photothermal therapy of tumor lesions

Metal based nanoparticles coated with a polymer functionalized with thiol groups and NH groups, said polymer preferably being selected among thiolated chitosan, thiolated and aminated alginic acid, thiolated and aminated hyaluronic acid, or a protein preferably selected from the group consisting of albumin and gelatin, or a synthetic thiolated and aminated polymer, preferably α-thio-ω-amino polyethylene glycols; wherein said groups are linked to a ligand of the integrin family receptors, preferably a peptide containing an integrin binding motif, and antibody or part of an antibody, a peptidomimetic or an aptamer, via a heterobifunctional crosslinker, the crosslinker bearing functional groups able to bind to amino groups, preferably selected from the group consisting of N-hydroxysuccinimidyl ester group (NHS ester), an isocyanate group (-NCO), an isothiocyanate group (-NCS), a Sulfo-N- hydroxysuccinimidyl ester group (sulfo-NHS ester), or a carboxylic acid group which is connected by activation with carbodiimide coupling agents; and/or a functional group able to bind thiol groups, preferably selected from the group consisting of: a maleimide group, a terminal vinyl group or a terminal alkyne group; and/or functional groups able to bind alkynes such as azides; and/or functional groups able to bind azides, such as alkynes.