The Editors have retracted this article [1] because Figs. 6a and 6c have been used in three other publications to represent scanning electron micrographs of different nanoparticles [2-4]. The data reported in this article are therefore unreliable. In addition, Fig. 3 was reproduced from [5] with retrospective permission and the credit line should read as follows: "Reprinted from Acta Biomaterialia, Volume 3, Zhang, J. and Misra, R.D.K., Magnetic drug-targeting carrier encapsulated with thermosensitive smart polymer: core-shell nanoparticle carrier and drug release response, pp. 838-850, copyright (2007) with permission from Acta Materialia Inc. Authors Abolfazl Akbarzadeh, Maryam Anzaby, Soodabeh Davaran, Sang Woo Joo and Mohammad Samiei agree to this retraction. Authors Younes Hanifehpour and Hamid Tayefi Nasrabadi have not responded to any correspondence about this retraction.