Fine particulate matter (PM 2.5) is the principal instigators of adverse health events, yet gaps still remain in understanding the mechanism mediating its toxic response. Similar to nanoparticles, PM 2.5, with large surface area to volume ratio, can absorb multipollutants in air, displaying toxicity profiles that are very different from those of coarse particles of the same composition. One particularly relevant interaction is that of PM 2.5 and the anthropogenic metals. In this study, we used carbon black nanoparticle (CBs) and metal ions as model materials to investigate the synergistic pulmonary toxicity and its mechanism. We demonstrated that excessive metal contaminants adsorbed on CBs contributed to the observed toxic effects both in vitro and in C57BL6 mice intratracheal instillation model. Significantly, we found that autophagy and lysosomal dysfunction accounted for the synergistic pulmonary toxic effect of co-exposure to CBs and metals. Our findings provide a new insight into understanding the toxicological and healthy effects of fine particles, which have potential to aid in mitigating their adverse health effect.

Prolonged therapeutic action over an extended period of time on single dose is vital in designing an ideal drug delivery system. Nanoparticle-based vehicles for drug delivery serves as an ideal technology, however, utilization of them remains controversial due to potential safety concerns and transient drug retention. Nanodiamonds (NDs), with excellent biocompatibility and diversity of potential conjugates, have emerged as alternative promising materials in this regard. Here, we developed sodium alginate functionalized NDs (fNDs) for drug delivery. Cisplatin (DDP) was chosen as a model drug and coated on the negatively charged fNDs clusters. Our work demonstrated that fNDs were capable of enhancing drug accumulation and retention time in tumor cells, leading to continued tumor cell killing effect after clearance of drug treatment. Furthermore, fNDs–DDP treatment improved drug safety compared to DDP treatment. Thus, this new platform may have strong potential for further biomedical application.

Carbon nanomaterials are the most studied materials in nanotechnology. There have been numerous studies on cytotoxicity assessments of carbon nanomaterials, which, however, often lead to controversy. It is generally considered that chemical and physical properties of carbon nanomaterials should have specific biological outcomes. More recent studies have identified the significance of environmental factors surrounding nanomaterial-treated cells. In this perspective, we mainly review culture medium-associated physicochemical insights on the cytotoxicity of carbon nanomaterials, which are largely based on studies in our laboratory. These studies established the close relationship and interplay among the physicochemical properties of the nanomaterials, culture medium, and their toxicological responses.

Gold nanoparticles (AuNPs) are often used as nanoscale vehicles to deliver drugs or biomolecules due to low cytotoxicity and high biocompatibility. Current research focuses on their application in cell or animal models, while their use in plants is limited because their ecotoxicological impact is poorly documented. Here, we examine the toxicity and fate of AuNPs in plants using oilseed rape as a model. We show that AuNPs will not affect the germination of rape seeds as well as the growth of the plantlet. Significantly, we demonstrate the effective translocation of AuNPs in plant tissues, and AuNPs will not interfere with the natural distribution of mineral nutrient elements in plant tissues. Our results demonstrate the mild effect of AuNPs on the growth of oilseed rape seedlings and suggest their potential application as vehicles for gene delivery in plants.

To explore the effects of the novel properties of carbon nanoparticles (CNPs) on cytotoxicity, the adsorption of serum proteins in cell culture medium on multi-walled carbon nanotubes and three kinds of carbon blacks was investigated. The uptake of CNPs by Hela cells was measured quantitatively using 99mTc radionuclide labeling and tracing techniques, and the dependence of CNPs uptake on serum proteins was examined. The cytotoxicity of CNPs in medium with and without serum was assayed by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] method. It was found that cellular uptake was much higher in cells exposed to CNPs in serum-free culture medium than those in culture medium with serum. Serum proteins adsorbed on CNPs attenuated the inherent cytotoxicity of CNPs, and the extent of toxicity attenuation increased with increasing amounts of serum proteins adsorbed on CNPs. The possible reasons responsible for the considerable influence of serum proteins on cytotoxicity were indicated.