The various embodiments herein provide a gold coated SPIONs with jagged surface. The gold coated SPIONs have a core and a shell. The core is a SPION molecule and the shell is a jagged gold layer. A non-uniform polymeric gap exists between the core and the shell. The embodiments also provide a method of producing the jagged gold coated SPIONs by mixing a colloidal dispersion of SPIONs with pH sensitive polymers. Adding a gold salt to the above mixture and reducing the gold salt to form jagged gold coated SPIONs.