Polyoxometalates (POMs) are metal-oxygen anionic clusters, which show huge potential for biomedical applications. The major drawback in using POMs in biomedicine is their inherent low cell delivery, mostly because of their negative charge, hampering translocation through hydrophobic membranes. Here, we propose to develop bio-conjugated POMs, asymmetrically functionalized with both cell-penetrating (CPPs) and homing peptides, for enhanced bioavailability and specificity.