Methods of delivering anionic agents in vivo using non-viral nanoparticle-based delivery systems

A method for in vivo targeted delivery of therapeutic payload to an individual in need thereof, said method comprising:

• (a) providing a polymeric delivery system comprising or having contained therein, or complexed with, the therapeutic payload, wherein the polymeric delivery system comprises non-viral nanoparticles comprising:
• a plurality of cationic chitosan polymers, polyethylene glycol and a peptide sequence, and wherein the non-viral nanoparticles comprise an internal core and the therapeutic payload is placed in or contained in the inner core, or the therapeutic payload is complexed to the inner core,
• and the polymeric delivery system is made by a method comprising:
• (i) reacting amine groups of chitosan with phthalic anhydride as a protection step;
• (ii) activating monomethoxy polyethylene glycol (mPEG-OH) with succinic anhydride to form mPEG-COOH;
• (iii) activating mPEG-COOH with thionyl chloride to form mPEG-COCl to form an activated PEG;
• . . . (vii) reacting the activated chitosan-PEG-COOH with a peptide sequence comprising a cell penetrating peptide, wherein said peptide sequence comprises a terminal amine, and wherein this reaction is done using EDC and DMAP as a catalyst to form chitosan-PEG-peptide;
• . . . and
• (viii) reacting the chitosan-PEG-peptide with hydrazine monohydrate to deprotect amine groups of chitosan,
• and wherein the plurality of cationic chitosan polymers are cross linked to each other to form the outer layer of the nanoparticle to generate an internal core;
• and the nanoparticles have an average diameter of between 5 to 300 nm;
• and
• (b) administering or delivering the non-viral nanoparticle to the individual.