Effects of carbon dots surface functionalities on cellular behaviors - Mechanistic exploration for opportunities in manipulating uptake and translocation.

Carbon dots (CDots) for their excellent optical and other properties have been widely pursued for potential biomedical applications, in which a more comprehensive understanding on the cellular behaviors and mechanisms of CDots is required. For such a purpose, two kinds of CDots with surface passivation by 3-ethoxypropylamine (EPA-CDots) and oligomeric polyethylenimine (PEI-CDots) were selected for evaluations on their uptakes by human cervical carcinoma HeLa cells at three cell cycle phases (G/G, S and G/M), and on their different internalization pathways and translocations in cells. The results show that HeLa cells could internalize both CDots by different pathways, with an overall slightly higher internalization efficiency for PEI-CDots.

Lanthanide (Gd(3+) and Yb(3+)) functionalized gold nanoparticles for in vivo imaging and therapy.

Nanoparticles are regularly used as contrast agents in bioimaging. Unlike other agents such as composite materials, nanoparticles can also be used for treating as well as imaging disease. Here we synthesized lanthanide functionalized gold nanoparticles that can be used for both imaging and therapy in vivo.

Biological effects of agglomerated multi-walled carbon nanotubes.

The physicochemical properties of nanomaterials play crucial roles in determining their biological effects. Agglomeration of nanomaterials in various systems is a common phenomenon, however, how agglomeration affects the biological consequence of nanomaterials has not been well investigated because of its complexity. Herein, we prepared variable sized agglomerates of oxidized multi-walled carbon nanotubes (O-MWCNTs) by using Ca(2+) and studied their cellular uptake and cytotoxicity in HeLa cells.

Chitosan-coated red fluorescent protein nanoparticle as a potential dual-functional siRNA carrier.

Aims: Developing safe and efficient nano vectors is critical for the success of siRNA therapy.

Materials & Methods: By encapsulating red fluorescent protein (RFP) with chitosan (CS), a dual-functional siRNA delivery nano vector, RFP@CS, has been synthesized.

Results: RFP@CS has an optimum size of 7-23 nm for siRNA delivery; and the fluorescence of RFP, protected by CS coating, provides an excellent probe to track the delivery of siRNA.

Biological effect of food additive titanium dioxide nanoparticles on intestine: an in vitro study.

Titanium dioxide nanoparticles (TiO2 NPs) are widely found in food-related consumer products. Understanding the effect of TiO2 NPs on the intestinal barrier and absorption is essential and vital for the safety assessment of orally administrated TiO2 NPs. In this study, the cytotoxicity and translocation of two native TiO2 NPs, and these two TiO2 NPs pretreated with the digestion simulation fluid or bovine serum albumin were investigated in undifferentiated Caco-2 cells, differentiated Caco-2 cells and Caco-2 monolayer.

Progress in the characterization and safety evaluation of engineered inorganic nanomaterials in food.

Nanotechnology has stepped into the food industry, from the farm to the table at home, in order to improve the taste and nutritional value, extend the shelf-life and monitor the food quality. In fact, as consumers we have already been in contact, via oral exposure, with a number of food products containing engineered nanomaterials (ENMs) more often than most people think. However, the fate of ENMs after entering the GI tract of the human body is not yet clearly understood.