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Denton Silver posted an update 1 week ago
Nanoscale magnetic field images of the magnetised magnetic nanoparticles spatially assigned to individual cells are superresolved by the NV centres within nanodiamonds conjugated with the magnetic nanoparticles with 20 nm resolutions. Our method offers a new platform for the super-resolution of optical magnetic imaging in biological samples conjugated with nanodiamonds and iron-oxide magnetic nanoparticles.Nanomedicine has huge potential in cancer therapy due to its advantages of improving the solubility, increasing the bioavailability and reducing the side effects of anticancer drugs. However, the intratumoral accumulation of anticancer nanomedicine is still extremely low owing to multiple physiological barriers to drug delivery; thus, it is inefficient for cancer treatments. Inspired by the communication between natural cells and the body environment, living cell-based anticancer therapeutics have been developed as promising drug carriers or active drugs for cancer therapy. In this review, we will survey recent advances in living cell-based anticancer therapeutics by leveraging their physiological characteristics, from long circulating properties to tumor-homing capacity and anticancer immune responses. In addition, future prospects of this field will be discussed.Dedicated chemistries for on-demand capture and release of biomolecules at the solid-liquid interface are required for applications in drug delivery, for the synthesis of switchable surfaces used in analytical devices and for the assembly of next-generation biomaterials with complex architectures and functions. Here we report the engineering of a binary self-assembling polypeptide system for reversible protein capture, immobilisation and controlled thermo-responsive release from a solid surface. The first element of the binary system is a universal protein substrate immobilised on a solid surface. This protein is bio-inspired by the neuronal SNAP25, which is the protein involved in the docking and fusion of synaptic vesicles to the synaptic membrane. The second element is an artificial chimeric protein engineered to include distinct domains from three different proteins Syntaxin, VAMP and SNAP25. These native proteins constitute the machinery dedicated to vesicle trafficking in eukaryotes. We removed approximnt for the engineering of future functional proteins with predictable folding and response to external stimuli.Clinically acceptable safety and efficacy are the most important issues for the design and synthesis of iron oxide MRI contrast agents. In order to meet the practical requirements, a kind of low molecular weight PAA-coated Fe3O4 nanoparticle (CS015) with super colloidal stability and low hypersensitivity benefitting from an ultrahigh carboxyl group density was developed in this study. The composition and physicochemical properties of the particles were characterized by TEM, XRD, FTIR and TGA. The ultrahigh density of COOH on the particles (33 COOH per nm2) was verified while a core size of 5.1 nm and a dynamic diameter of 41 nm with a narrow distribution were also achieved. The particles still showed excellent dispersity and stability even after a spray-drying or freeze-drying process, exposure to high temperature sterilized conditions and long-term storage. The nanoparticles could quickly capture iron ions in bulk solution which was confirmed by ITC results, and the bioactive iron concentration of CS015 was greatly decreased (0.54 ± 0.05 mg L-1) compared to that of commercially available ferumoxytol, iron sucrose and VSOP. Free iron ion release was 1120 times lower than the toxic concentration of iron. An excellent biocompatibility of CS015 with no obvious cytotoxicity and low risk of hypersensitivity has been manifested by cytotoxicity experiments and a passive cutaneous anaphylaxis test. The T1 and T2-weighted MRI contrast effects both in vitro and in vivo have also been verified which made CS015 a potential dual MRI contrast agent. check details Furthermore, theoretically calculated conformation was speculated and all the advantages mentioned above were benefited from the three dimensional brush-like texture of CS015. Therefore, these merits make the CS015 nanoplatform highly suitable in diagnostic applications as a MRI contrast agent.Nitrite (NO2 -) is one of the important pollutants in food and the environment, which can seriously endanger the health of human beings. Therefore, detecting nitrite in food, environmental and biological samples is very significant for health monitoring. Herein, polymer carbon dots (PCDs) doped with nitrogen and phosphorus were prepared by polymerization of ascorbic acid (AA) and polyethylenimine (PEI) with phosphoric acid, and exhibited excellent stability, adjustable fluorescence emissions and good biocompatibility. It was found that the PCDs presented a sensitive response to nitrite (NO2 -), and they were successfully applied for NO2 – analysis in water and milk samples, and the dynamic monitoring of nitrite entry into Hep-2 cells.Flexible humidity sensors enabling the real-time monitoring of the humidity level in the environment or around the human body have increasing application prospects in electronic skin and personal healthcare. Tremendous efforts have been devoted to improve the performance of humidity sensors, but little effort has been made to investigate the effect of the substrate. This work reveals the vital role of the sensor substrate in determining the humidity sensing performance by performing a comparative study. A porous, hydrophobic and flexible liquid crystal polymer (LCP) substrate is employed to speed up the response and recovery processes and boost the sensitivity simultaneously. Graphene oxide-based sensors fabricated on the LCP substrate exhibit 8.1 and 3.2 times higher response and recovery speeds, respectively, and 1.37 times higher sensitivity than corresponding sensors generated on a smooth SiO2 substrate. Similar performance improvement is observed when reduced graphene oxide and carbon nanocoils are deployed as the humidity sensing materials. These distinct structure-related properties enable the fabrication of humidity sensors to monitor various human activities, including fast and normal respiration, skin hydration, finger movement, etc. Furthermore, a positive correlation between the sensitivity and the oxygen content in carbon materials is revealed.