The rapid advancement of nanotechnology in recent years has fuelled a burgeoning interest in the field of nanoparticle research, in particular, its application in the medical arena. A constantly expanding knowledge based on a better understanding of the properties of gold nanoparticles (AuNPs) coupled with relentless experimentation means that the frontiers of nanotechnology are constantly being challenged. At present, there seems to be heightened interest in the application of AuNPs to the management of cancer, encompassing diagnosis, monitoring and treatment of the disease. These efforts are undertaken in the hope of revolutionizing current methods of treatment and treatment strategies for a multifactorial disease such as cancer. This review will focus on the current applications of AuNPs in cancer management.

In recent decades, advances in nanotechnology engineering have given rise to the rapid development of many novel applications in the biomedical field. However, studies into the health and safety of these nanomaterials are still lacking. The main concerns are the adverse effects to health caused by acute or chronic exposure to nanoparticles (NPs), especially in the workplace environment. The lung is one of the main routes of entry for NPs into the body and, hence, a likely site for accumulation of NPs. Once NPs enter the interstitial air spaces and are quickly taken up by alveolar cells, they are likely to induce toxic effects. In this review, we highlight the different aspects of lung toxicity resulting from NP exposure, such as generation of oxidative stress, DNA damage and inflammation leading to fibrosis and pneumoconiosis, and the underlying mechanisms causing pulmonary toxicity.

In the present study, quantum dot (QD) capped magnetite nanorings (NRs) with a high luminescence and magnetic vortex core have been successfully developed as a new class of magnetic-fluorescent nanoprobe. Through electrostatic interaction, cationic polyethylenimine (PEI) capped QD have been firmly graft into negatively charged magnetite NRs modified with citric acid on the surface. The obtained biocompatible multicolor QD capped magnetite NRs exhibit a much stronger magnetic resonance (MR) T2* effect where the r2* relaxivity and r2*/r1 ratio are 4 times and 110 times respectively larger than those of a commercial superparamagnetic iron oxide. The multiphoton fluorescence imaging and cell uptake of QD capped magnetite NRs are also demonstrated using MGH bladder cancer cells. In particular, these QD capped magnetite NRs can escape from endosomes and be released into the cytoplasm. The obtained results from these exploratory experiments suggest that the cell-penetrating QD capped magnetite NRs could be an excellent dual-modality nanoprobe for intracellular imaging and therapeutic applications. This work has shown great potential of the magnetic vortex core based multifunctional nanoparticle as a high performance nanoprobe for biomedical applications.

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Nanotechnology has created opportunities for engineers to manufacture superior and more efficient devices and products. Nanomaterials (NMs) are now widely used in consumer products as well as for research applications. However, while the lists of known toxic effects of nanomaterials and nanoparticles (NPs) continue to grow, there is still a vast gap in our knowledge about the genotoxicity of NMs. In this paper, we highlight some NMs of interest and discuss the current in vivo and in vitro studies into genotoxic effects of NMs.

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Gold nanoparticles (AuNPs) have diverse applications in the biomedical industry such as in diagnosis, labeling, delivering and sensing. Despite their prevalent medical use, nanotoxicity induced by AuNPs is still largely unknown. We have previously shown that AuNPs could exert cytotoxic effects on lung fibroblasts. In this study, we investigated the in vitro toxicological effects of AuNPs in small airway epithelial cells (SAECs) which are the first cells of contact for inhaled NPs and compared expression of metallothionein (MT), a reactive oxygen species scavenger, in SAECs and lung fibroblasts in vitro. Transmission electron microscopy (TEM) and energy-dispersive X-ray (EDX) spectroscopy study revealed cellular uptake of aggregates of AuNPs into the cytoplasm at the ultrastructural level. A significant increase in lipid peroxide as well as substantial DNA damage and cytotoxicity was observed in AuNP-treated cells. For MT expression, AuNPs induced down-regulation of the MT-1X isoform in SAECs, but up-regulation of the MT-1X and MT-2 A isoforms in MRC5 lung fibroblasts. The present study suggests that AuNPs could induce oxidative stress-related cytotoxicity and genotoxicity in SAECs.

Cell surface receptors play an important role in mediating cell communication and are used as disease biomarkers and therapeutic targets. We present a one-pot molecular toolbox, which we term the split proximity circuit (SPC), for the autonomous detection and visualization of cell surface receptor clusters. Detection was powered by antibody recognition and a series of autonomous DNA hybridization to achieve localized, enzyme-free signal amplification. The system under study was the human epidermal growth factor receptor (HER) family, that is, HER2:HER2 homodimer and HER2:HER3 heterodimer, both in cell lysate and in situ on fixed whole cells. The detection and imaging of receptors were carried out using standard microplate scans and confocal microscopy, respectively. The circuit operated specifically with minimal leakages and successfully captured the receptor expression profiles on three cell types without any intermediate washing steps.