Zn1−xGdxS (x = 0.1, 0.2 and 0.3) nanoparticles for magnetic resonance imaging and optical fluorescence imaging

Abstract

This work proposes chemically synthesized Gd doped ZnS nanoparticles based system for potential use as contrast enhancing agent for both optical fluorescence imaging and magnetic resonance imaging. Two different Gd doped ZnS nanoparticle systems were synthesized. These systems were (i) graphene oxide–Zn1−xGdxS (x = 0.1, 0.2 and 0.3) nanoparticle composites and (ii) chitosan coated Zn1−xGdxS (x = 0.1, 0.2 and 0.3) nanoparticles. Gd formed solid solution with ZnS in all the six as-synthesized samples. Gd doped ZnS nanoparticles in both cases exhibited both longitudinal and transverse relaxivity values. A clear dependence the relaxivity values on the composition of the nanoparticles and the nanoparticle environment (presence and absence of graphene oxide) was observed. Between the two cases, values of the longitudinal and transverse relaxivity were higher for the graphene oxide–Zn1−xGdxS composites. It is also shown that Gd doped ZnS nanoparticle can be used for fluorescence imaging also. Gd doped ZnS nanoparticle exhibited biocompatibility towards the MCF-7 cell line.