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The blood-brain barrier (BBB) remains an obstacle for many drugs to reach the brain. A strategy to cross the BBB is to modify nanocarrier systems with ligands that bind to endogenous receptors expressed at the BBB to induce receptor-mediated transport. The aim of the present study was to investigate the potential of polymersomes composed of the amphiphilic diblock copolymer poly(dimethylsiloxane)-block-poly(2-methyl-2-oxazoline), PDMS-b-PMOXA, for active targeting of brain capillary endothelial cells. We conjugated PDMS-b-PMOXA polymersomes to the anti-human insulin receptor antibody 83-14 and studied their uptake by brain capillary endothelial cells. Transmission electron micrography and light scattering measurements revealed the self-assembly of the block copolymers into 200 nm vesicles after extrusion. Fluorescence correlation spectroscopy was employed to calculate the number of antibodies coupled to one polymersome. Binding and uptake of the polymersomes conjugated to 83-14 mAb were studied in the human BBB in vitro model hCMEC/D3 expressing the human insulin receptor. Competitive inhibition with an excess of free 83-14 mAb demonstrated the specificity of cellular binding and uptake. Our results suggest that PDMS-b-PMOXA polymersomes conjugated to 83-14 mAb may be suitable nanocarriers for drug delivery to the brain.

The field of nanoscience is expected to make significant contributions to contemporary medicine by providing unique solutions to critical problems. These solutions require the design of hybrid materials/systems with new properties and functionalities. This review focuses on spherical polymer nanocompartments (capsules and vesicles) and describes their potential in a wide variety of medical applications that range from passive drug carriers to active nanoreactors to artificial organelles. Here, we place emphasis on the complex requirements that a polymer assembly must fulfill for consideration in the medical domain. In terms of stability and chemical diversity, synthetic polymer compartments are superior to currently marketed liposomes, thereby supporting their modification for targeting approaches, stimuli-responsiveness, and multifunctionality. The authors present the latest concepts and examples based on the encapsulation/entrapment of biomolecules (e.g., enzymes and proteins) for the development of active nanosystems for application in the medical domain.

To reduce the weight of bracket and production cost of the naval gun, the aluminum board welded structure is used. The strength check analysis must be conducted for the fire safety. Firstly, based on the three-dimensional CAD model of the bracket and according to the design date, the geometry of model was simplified. Secondly, the FEM model of the bracket was built with the FEM software MSC. Patran, and the FEM strength analysis was made. Finally, the deformation and stress for the key position was obtained, the strength check was made for the bracket. The result shows that the welding structure is meet with the strength condition after considering the safety factor of 1.5.

Marine Camblin,1 Pascal Detampel,1 Helene Kettiger,1 Dalin Wu,2 Vimalkumar Balasubramanian,1,* Jörg Huwyler1,*1Division of Pharmaceutical Technology, 2Department of Chemistry, University of Basel, Basel, Switzerland*These authors contributed equally to this workAbstract: Quantum dots (QDs) are highly fluorescent and stable probes for cellular and molecular imaging. However, poor intracellular delivery, stability, and toxicity of QDs in biological compartments hamper their use in cellular imaging. To overcome these limitations, we developed a simple and effective method to load QDs into polymersomes (Ps) made of poly(dimethylsiloxane)-poly(2-methyloxazoline) (PDMS-PMOXA) diblock copolymers without compromising the characteristics of the QDs. These Ps showed no cellular toxicity and QDs were successfully incorporated into the aqueous compartment of the Ps as confirmed by transmission electron microscopy, fluorescence spectroscopy, and fluorescence correlation spectroscopy. Ps containing QDs showed colloidal stability over a period of 6 weeks if stored in phosphate-buffered saline (PBS) at physiological pH (7.4). Efficient intracellular delivery of Ps containing QDs was achieved in human liver carcinoma cells (HepG2) and was visualized by confocal laser scanning microscopy (CLSM). Ps containing QDs showed a time- and concentration-dependent uptake in HepG2 cells and exhibited better intracellular stability than liposomes. Our results suggest that Ps containing QDs can be used as nanoprobes for cellular imaging.Keywords: quantum dots, polymersomes, cellular imaging, cellular uptake