Synthesis and Characterization of Amphiphilic Gd(III) Complexes: Gd-DTPA-BA

An MRI-guided targeting dual-responsive drug delivery system for liver cancer therapy

The targeting dual-responsive drug delivery system was employed for cancer treatment as a positive strategy. Herein, Lactobionic acid (LA)-modified and non-modified UV/reduction dual-responsive molecules (10,10-NB-S-S-P-LA and 10,10-NB-S-S-P-OMe) were synthesized. Functional magnetic resonance imaging (MRI) contrast agent (12,12-NB-DTPA-Gd) was mixed with 10,10-NB-S-S-P-LA or 10,10-NB-S-S-P-OMe in the optimal ratio (3:1) to develop targeted empty liposomes (GNSPL) or non-targeted empty liposomes (GNSPM) with superior UV/reduction dual-responsiveness, biocompatibility and magnetic resonance imaging (MRI) performance. The drug-loaded liposomes (GNSPLD and GNSPMD) can keep stable in two weeks, and the drug cumulative release rate reached to the maximum under dual stimulation of ultraviolet (UV) and reducing agent (TCEP). The treatment with GNSPLD + UV significantly inhibited the growth and migration of cancer cells in vitro. The GNSPLD liposomes were more effectively accumulated in tumor site than GNSPMD liposomes, due to the targeting property of GNSPLD liposomes. The treatment with GNSPLD + UV showed a better therapeutic efficacy than Doxorubicin (DOX) in vivo, and almost no side effects during the treatment period. Thus, the MRI-guided targeting dual-responsive drug delivery system provided a reliable therapeutic strategy for treating liver cancer.

Ultrasound lighting up AIEgens for potential surgical navigation

Multifunctional contrast-enhanced agents suitable for application in surgical navigation by taking advantage of the merits of their diverse imaging modalities at different surgical stages are highly sought-after. Herein, an amphipathic polymer composed of aggregation-induced emission fluorogens (AIEgens) and Gd³⁺ chelates was successfully synthesized and assembled into ultrasound responsive microbubbles (AIE-Gd MBs) to realize potential tri-modal contrast-enhanced ultrasound (US) imaging, magnetic resonance imaging (MRI), and AIEgen-based fluorescence imaging (FI) during the perioperative period. Through ultrasound targeted microbubble destruction (UTMD) and cavitation effect, the as-prepared AIE-Gd MBs went through a MBs-to-nanoparticles (NPs) conversion, which not only resulted in targeted accumulation in tumor tissues but also led to stronger fluorescence being exhibited due to the more aggregated AIE-Gd molecules in the NPs. As a proof-of-concept, our work proposes a strategy of US-lit-up AIEgens in tumors which could offer a simple and powerful tool for surgical navigation in the future.

Synthesis of heteronanostructures for multimodality molecular imaging-guided photothermal therapy

Here, a heteronanostructure (Au-Fe₃O₄@PDA-PEG-DTPA-Gd) has been constructed for multimodality molecular imaging (T₁-/T₂-weighted MRI and CT imaging)-guided PTT of cancer by combination of Au-Fe₃O₄, PDA shell and DTPA-Gd into one nanoplatform.