Exosome-based drug delivery systems and their therapeutic applications

In the past few decades, scientists have actively worked on developing effective drug delivery systems (DDSs) as means to control life-threatening diseases and challenging illnesses.

Fulleropyrrolidine-functionalized ceria nanoparticles as a tethered dual nanosystem with improved antioxidant properties

Dual-tethered nanosystems which combine different properties at the nano scale represent a new fascinating frontier of research. In the present work, we present an example of a dual nanosystem designed to enhance the radical scavenging performances. Fulleropyrrolidine has been bonded to cerium oxide nanoparticles (nanoceria) to form a dual tethered system. Fulleropyrrolidine, bearing a silyl-alkoxide group, has been chemically bonded to the nanoceria surface, providing unprecedented antioxidant activity. This effect has been evaluated using an L929 mouse fibroblast cell line exposed to UV light. The fulleropyrrolidine molecules tethered to nanoceria enhance the radical scavenging properties of the oxide. At the same time, fulleropyrrolidine mitigates the potential toxicity of nanoceria at high doses. On the other hand, cerium oxide nanoparticles provide a strong hydrophilicity to the dual nanosystem, ensuring the administration in a cellular environment and preventing macroscopic aggregation of fulleropyrrolidine. The rational assembly of two different components in one nanosystem appears as a promising route for the development of "smarter" medical and cosmetic devices.

Evaluating the Creaming of an Emulsion via Mass Spectrometry and UV-Vis Spectrophotometry

The creaming behavior of a turbid oil-in-water emulsion was observed via the processes of multiphoton ionization time-of-flight mass spectrometry (MPI-TOFMS) and ultraviolet-visible spectrophotometry (UV-vis), and the results were compared. The transmittance measurement by UV-vis showed that the turbidity of the toluene emulsion was decreased with time. However, non-negligible errors are common in the measurement of a sample with high turbidity. The online measurement by MPI-TOFMS detected many spikes in the time profile, which revealed the existence of toluene droplets in the emulsion. A smooth time profile suggested that the signal intensity had initially increased, and then decreased with time; the initial concentration of toluene was 3 g/L, which had decreased by half after 60 min. The signal behavior obtained using MPI-TOFMS differed only slightly from that obtained using UV-vis. Since a change in turbidity is not the same as a change in the local concentration of an oil component, MPI-TOFMS is useful for the analysis of a turbid emulsion and offers additional information concerning the creaming phenomenon of an emulsion.