Application of Red Cell Membrane in Nanobiotechnology

Red cells are full of unique biological properties such as immune evasion and molecular-specific permeability. These properties originate from various membrane proteins on the surface of the cell membrane. For this reason, red cell membrane is coated on nanomaterials or sensors to bestow the functionalities of the membrane proteins. In this chapter, various types of membrane proteins of red cell and its functions are described. Also, the following two experimental procedures are summarized: (I) the extraction of red cell membrane containing membrane proteins and (II) coating of the extracted cell membrane onto the nanoparticles and solid surface of sensors. Finally, the applications of red cell membrane in drug delivery system and biosensor are discussed

Advances in AFM Imaging Applications for Characterizing the Biophysical Properties of Amyloid Fibrils

Although the formation mechanism of amyloid fibrils in bodies is still debated, it has recently been reported how amyloid fibrils can be formed in vitro. Accordingly, we have gained a better understanding of the self-assembly mechanism and intrinsic properties of amyloid fibrils. Because the structure of amyloid fibrils consists of nanoscaled insoluble strands (a few nanometers in diameter and micrometers long), a special tool is needed to study amyloid fibrils at length. Atomic force microscopy (AFM) is supposed to be a versatile toolkit to probe such a tiny biomolecule. The physical/chemical properties of amyloid fibrils have been explored by AFM. In particular, AFM enables the visualization of amyloid fibrillation with different incubation times as well as the concentrations of the formed amyloid fibrils as affected by fibril diameters and lengths. Very recently, the minute structural changes and/or electrical properties of amyloid fibrils have been made by using advanced AFM techniques including dynamic liquid AFM, PeakForce QNM (quantitative nanomechanical mapping), and Kelvin probe force microscopy (KPFM). Herein, we summarize the biophysical properties of amyloid fibrils that are newly discovered with the help of those advanced AFM techniques and suggest our perspectives and future directions for the study of amyloid fibrils

Phosphorus in the Young Supernova Remnant Cassiopeia A

Phosphorus (^(31)P), which is essential for life, is thought to be synthesized in massive stars and dispersed into interstellar space when these stars explode as supernovae (SNe). Here, we report on near-infrared spectroscopic observations of the young SN remnant Cassiopeia A, which show that the abundance ratio of phosphorus to the major nucleosynthetic product iron (^(56)Fe) in SN material is up to 100 times the average ratio of the Milky Way, confirming that phosphorus is produced in SNe. The observed range is compatible with predictions from SN nucleosynthetic models but not with the scenario in which the chemical elements in the inner SN layers are completely mixed by hydrodynamic instabilities during the explosion

Dynamical Response of Nanomechanical Resonators to Biomolecular Interactions

We studied the dynamical response of a nanomechanical resonator to biomolecular (e.g. DNA) adsorptions on a resonator's surface by using a theoretical model, which considers the Hamiltonian H such that the potential energy consists of elastic bending energy of a resonator and the potential energy for biomolecular interactions. It was shown that the resonant frequency shift of a resonator due to biomolecular adsorption depends on not only the mass of adsorbed biomolecules but also the biomolecular interactions. Specifically, for dsDNA adsorption on a resonator's surface, the resonant frequency shift is also dependent on the ionic strength of a solvent, implying the role of molecular interactions on the dynamic behavior of a resonator. This indicates that nanomechanical resonators may enable one to quantify the biomolecular mass, implying the enumeration of biomolecules, as well as gain insight into intermolecular interactions between adsorbed biomolecules on the surface.Comment: 17 page, 4 figures, accepted for publication at PRB. Physical Review B, accepte

Characteristics of high efficiency current charging system for HTS magnet with solar energy

AbstractIn terms of electrical energy, the technical fusion with solar energy system is promisingly applied in order to improve the efficiency in the power applications, since the solar energy system can convert an eternal electric energy in all-year-around. As one of such power applications, we proposed a current charging system for HTS magnet combined with solar energy (CHS). As this system can operate without external utility power to charge the HTS load magnet due to the solar energy, the operating efficiency is practically improved. The power converter, which is interfaced with solar energy and HTS magnet systems, plays an important role to transfer the stable electric energy and thus, the stabilized performance of the converter with solar energy system is one of essential factors. In this study, we investigated various charging performances under different operating conditions of the converter. In addition, operating characteristics have been analyzed by solving solar cell equivalent equations based on circuit simulation program