Corrigendum to “Fabrication and characterisation of curcumin loaded pH dependent sodium alginate-g-poly(acryloyl phenylalanine)-cl-ethylene glycol vinyl ether-cohydroxyethyl acrylate hydrogels and their in-vitro, in-vivo and toxicological evaluation studies” [J. Drug Deliv. Sci. Technol. 51 (2019) 438–453]