Synthesis of colloidal aqueous suspensions of a layered gadolinium hydroxide: a potential MRI contrast agent

Abstract

A layered gadolinium hydroxychloride (LGdH), [Gd2(OH)5(H2O)x]Cl, was synthesized from an aqueous solution of GdCl3.6H2O. The X-ray diffraction (XRD) and the selected area electron diffraction (SAED) studies showed that this compound crystallizes in the orthorhombic structure (a = 12.88(4) A, b = 7.30(2) A, and c = 8.46(3) A) which is isostructural with [Eu2(OH)5(H2O)x]Cl. Interestingly, this layered material was readily dispersed and led to a stable colloidal nanosheet in aqueous medium. The obtained colloidal solutions were characterized by the evaluation of their stability in acidic solution, their in vitro cytotoxicity, and their magnetic resonance imaging (MRI) relaxation properties. It is reported that the relaxometry analysis of LGdH suspensions exhibits a sufficient contrast effect for T1 weighted magnetic resonance imaging.

Recent development in 2D materials beyond graphene

“…Nanosheets obtained from ultrasonication are highly crystalline and micrometer in size as confirmed from HRTEM. However, it is also reported that, the in-plane cleavage of layered materials in gadolinium hydroxide with an interlayer of Cl -anion results in flakes of ~100 nm size [181]. Schematic representation of the various liquid exfoliation process is presented in Figure. 7.…”

Reverse microemulsion synthesis of layered gadolinium hydroxide nanoparticles

“…Moreover, LRHs possess the magnetic and fluorescent properties of the rare-earth metals they contain, which could give additional benefits. The combination of ion exchange intercalation chemistry and rare earth elements in the layers can lead to integrated materials with many applications in medical science [28,29], catalysis [30], separation science [26], sensor technologies [31], and luminescence devices [5,27,[32][33][34][35][36][37][38][39][40]. Some studies have focused on incorporating sensitizers or quenchers to tune the colour emission of LRH hybrids, for instance [3,5,27].…”

“…An alternative route to preclude free Gd 3+ getting into solution is to incorporate it into an inorganic matrix, and hence layered gadolinium hydroxides (LGdHs) might be viable contrast agents [43]. The potential of LGdHs in this regard has been explored in several reports [28,29,43,44], and the results obtained are promising. The LGdH matrix has also attracted a little attention for use as a drug delivery system, with the intercalation of several pharmaceutically active molecules including antibiotics, amino acids, and microRNA [43,45].…”

Bio-Layered Double Hydroxides Nanohybrids for Theranostics Applications

“…Byeon et al have developed another type of LDH containing only Gd metal (LGdH) for bimodal imaging function (Fig. 6b) [63,101]. From the results of cytotoxicity test and T 2 -weighted MRI experiment in vivo, the stable colloid of LGdH nanosheets modified with FITC and PEG was found to be were clearly observed due to the structural substitution of the Ln in the LDH layers [103].…”