polymeric nanoparticles with a hydrophobic core and a hydrophilic shell are formed from : 1 ) n - isopropyl acrylamide , at a molar ratio of about 50 % to about 90 %, and preferably 60 % for specific delivery routes such as oral or parenteral ; either water - soluble vinyl derivatives like vinylpyrolidone or vinyl acetate , or water insoluble vinyl derivatives like methyl methacrylate or styrene , at a molar ratio of about 10 % to about 30 %; and acrylic acid , at a molar ratio of about 10 % to about 30 %. the formed nanoparticles may be optionally surface functionalized using reactive groups present in aa , including pegylation , or conjugation of moieties such as chemotherapeutics , contrasting agents , antibodies , radionucleides , ligands , and sugars , for diagnostic , therapeutic , and imaging purposes . the polymeric nanoparticles are preferably dispersed in aqueous solutions . the polymeric nanoparticles incorporate one or more types of medicines or bioactive agents in the hydrophobic core ; on occasion , the medicine or bioactive agent may be conjugated to the nanoparticle surface via reactive functional groups . the polymeric nanoparticles are capable of delivering the said medicines or bioactive agents through oral , parenteral , or topical routes . the polymeric nanoparticles allow poorly water soluble medicines or bioactive agents , or those with poor oral bioavailability , to be formulated in an aqueous solution , and enable their convenient delivery into the systemic circulation .