Zi Sophia Gu
University of New South Wales,Australia
Title: Engineered clay nanoparticles for cancer treatment and diagnosis
Biography
Biography: Zi Sophia Gu
Abstract
Recent progress in material chemistry has enabled scientists to combine therapeutic and diagnostic agents on a single nanoplatform, which is designated as theranostics [1]. However, it remains a challenge to achieve theranostics with safety and high performance. We utilised a clay nanosheet LDH as the carrier of Mn(II) and anti-cancer drug 5-FU, and synthesised a new nanocomposite with outstanding pH-ultrasensitive T1-MRI performance and enhanced drug delivery efficiency [2,3] (Figure 1). Mn(II) element was doped in LDH nanostructure by isomorphic substitution to synthesis Mn-LDH nanosheets. The generated Mn-LDH (~50nm) showed an ultrahigh T1-weighted relaxivity of 9.48 mM-1s-1 at pH 5, possibly caused by the unique microstructure of Mn ions in Mn-LDHs. The relaxivity of Mn-LDH was highly sensitive to pH, which increased sixfold when pH was reduced from 7.4 to 7.0. The Mn-LDH was effectively internalised in HT29 cells, and the anti-cancer efficiency of 5-FU was enhanced by LDH delivery (IC50=1.54 µg/ml). The in vivo MRI evaluation showed an accumulation of Mn-LDH in tumour compared with liver and kidney, and the MRI signal maintained in tumour for 72 h. The second part of this talk will present a MnLDH@SPION nanocomposite as a pH-sensitive T1/T2 dual modal MRI contrast agent, hyperthermia agent and efficient drug carrier. The nanocomposite showed T1-weighted relaxivity increased from 1.88 to 6.23 mM-1s-1 and T2-weighted relaxivity from 226.18 to 367.25 mM-1s-1. This pH-sensitive and high relaxivity is not found in SPION as T2-MRI contrast agent. The MnLDH@SPION nanocomposite also has mild hyperthermia and efficient drug delivery properties.