Simultaneous Exposure of Different Nanoparticles Influences Cell Uptake

Drug delivery using nano-sized carriers holds tremendous potential for curing a range of diseases. The internalisation of nanoparticles by cells, however, remains poorly understood, restricting the possibility for optimising entrance into target cells, avoiding off-target cells and evading clearance. The majority of nanoparticle cell uptake studies have been performed in the presence of only the particle of interest; here, we instead report measurements of uptake when the cells are exposed to two different types of nanoparticles at the same time. We used carboxylated polystyrene nanoparticles of two different sizes as a model system and exposed them to HeLa cells in the presence of a biomolecular corona. Using flow cytometry, we quantify the uptake at both average and individual cell level. Consistent with previous literature, we show that uptake of the larger particles is impeded in the presence of competing smaller particles and, conversely, that uptake of the smaller particles is promoted by competing larger particles. While the mechanism(s) underlying these observations remain(s) undetermined, we are partly able to restrain the likely possibilities. In the future, these effects could conceivably be used to enhance uptake of nano-sized particles used for drug delivery, by administering two different types of particles at the same time.

Nanoencapsulated PCM slurries for the development of thermoregulating gypsums

Gypsums with improved thermal properties have been obtained using a thermoregulatory nanocapsulated slurry (NPCS) as additive. In order to determine the effects of the slurries in the gypsum, physical, mechanical and thermal properties of the different composite materials (gypsum – polystyrene nanoparticles (PS) or nanocapsules (NPCM)) have been studied. Concentrated slurries from polystyrene nanoparticles without (PSS) and with encapsulated phase change material (NPCS) have been synthesized. Firstly, gypsum blocks made of nanoparticles/hemihydrate with mass ratios ranging from 0.0 to 0.42 have been produced from PSS, in order to determine the optimal weight ratio with the best mechanical/physical characteristics. Then, the thermal gypsum block from NPCM/hemihydrate has been prepared at the selected weight ratio. Although PS and NPCM addition reduces the mechanical properties, all the developed materials satisfied the mechanical European regulation EN 13279-2 which limits the mechanical characteristics of gypsums composites. The gypsum composites with PS nanoparticles presented a reduction of the thermal conductivity, so these materials can be used as insulating material. The gypsum composite with NPCM/Hem = 0.3 had an improvement in the thermal storage capacity of 88.76 % and seems to be a good alternative for applying the thermal energy storage technology in buildings.

Preparation of Polymeric Nanomaterials Using Emulsion Polymerization

Nanoparticles are said to be active particles which are entrapped in the surface of the polymeric core. Since nanoparticles were used in medical and biotechnological fields, there is a great demand in the preparation of nanoparticles. Nanoparticles are prepared from different substances; mainly, polymer material is used in the field of preparing nanomaterials. There are different methods involved in the preparation of nanoparticles from the polymer. Various experiments and research studies were carried out on the basic preparation of nanoparticles. Emulsion polymerization could be used to make polymeric nanoparticles with a high solid concentration without the need of surfactants. To make carboxylate polystyrene beads or amidine polystyrene nanoparticles, polymeric nanocolloids containing surface functional groups were produced. In this research, the preparation of nanoparticles from emulsion polymerization is represented along with the size and distribution material.