Significant cell uptake of Gd(III)-diphenylphosphoryl-diphenylphosphonium complexes: evidence for a new conformationally-dependent tumour cell targeting vector.

The synthesis, characterisation, and tumour cell uptake of six novel Gd(III)-diphenylphosphoryl-diphenylphosphonium complexes are reported. The propyl-linked Gd(III) complexes can accumulate inside human glioma cells at prodigious levels, approaching 1200%, over the parent triphenylphosphonium salts. DFT and quantum chemical topology analyses support a new type of conformationally-dependent tumour cell targeting vector.

Gadolinium theranostics for the diagnosis and treatment of cancer.

According to the World Health Organization (WHO), there were 18.1 million new cancer cases and 9.6 million cancer deaths reported worldwide in 2018. These numbers are expected to rise over the next decade, and the development of new and effective cancer treatments and diagnostic tools is urgently required, particularly for aggressive and intractable malignant cancers such as those of the brain. An exciting field of cancer research involves combining therapeutic and diagnostic tools into a single 'theranostic' platform. The role of theranostics in the personalized management of oncology patients is increasing, as is the demand for new types of theranostic agents. Some of the most promising cancer theranostics exploit the lanthanoid metal gadolinium, an element possessing favourable therapeutic and imaging properties.

Synthesis and tumour cell uptake studies of gadolinium(III)-phosphonium complexes.

The synthesis of a new series of Gd(III)-arylphosphonium complexes is described and the solution stability of selected compounds is reported. Their lipophilicity and uptake in human glial (SVG p12) and human glioblastoma multiforme (T98G) cell lines are presented. The in vitro cytotoxicity of all complexes was determined to be low at therapeutically-relevant concentrations. Selected Gd(III) complexes are potential candidates for further investigation as theranostic agents.