| abstract |
The invention discloses injectable hydrogels which are in the form of crosslinked nano beads or particle in the size range 5 nm to 10 μm, comprising PAMAM dendrimer with asymmetrical peripheral end groups such that one of the terminal groups is involved in formation of hydrogel and the other in involved in the conjugation of drugs or imaging agents and their methods of preparation. The said gel is formed by reaction of the PAMAM dendrimer with asymmetrical end groups with other polymer wherein the other polymer is selected from the group of linear, branched, hyperbranched or star shaped polymers with functionalized terminal groups. The PAMAM dendrimer with asymmetrical terminal groups consists of a Generation 2 and above PAMAM dendrimer with symmetrical end groups modified using the amino acids or their modified forms. The gel disclosed in the present invention is formed as small crosslinked particles in the size range 25 nm to 10 μm and is suitable for injectable delivery of hydrogel to any of the body orifices, tissues by intramuscular or subcutaneous route and ocular delivery for the purpose of therapeutic treatment and imaging. |