Papers by Keyword: Protein

Abstract: MC3T3-E1 cell differentiation and related surface potentials of rutile-type TiO₂ scales formed on Ti are controlled by varying the Ti heat treatment conditions in a N₂ atmosphere containing a trace amount of O₂. The zeta potentials of the samples heated at 873 and 973 K for 1 h show large negative and positive values, respectively, while cell differentiation on the surface is enhanced in both cases (14 days incubation). In the case of untreated Ti, the cell differentiation diminishes and the zeta potential becomes more neutral. Protein detection by an immunogold-labeling technique and Ca and P detection by time-of-flight secondary ion mass spectrometry reveal that Ca and P, rather than an adhesive protein such as fibronectin, predominantly adsorbed on the scales formed in 1 h at 873 and 973 K, respectively. In the case of untreated Ti, both fibronectin and a non-adhesive protein such as albumin adsorbed, but no Ca and P were detected. The present findings illuminate the relationship between charged surfaces and MC3T3-E1 cellular response.

Abstract: This research addresses the challenges of sustainable use of natural polymers, including in technical fields. One of the leading trends in science and industry headway today lies in designing advanced functional materials, e.g. for manufacturing medical items, technical devices, food-processing tools et al. For this purpose, universally applicable technological processes are being developed, including in biotechnology. One of the main goals of this research is to explore ways to consolidate living systems, by instilling in them desirable physical and chemical properties so as to diversify their applications, including in technical fields. Polymers structure and properties have been investigated via raster electron microscopy, spectral analysis, et al.

Abstract: Mesoporous silica (MPS) coatings on hydroxyapatite (HAp) granules and their protein adsorptive capabilities were studied. MPS particles were coated on HAp granules using a dip-coating method, but the HAp granules were not totally covered by the MPS particles. A silica interlayer was formed on the HAp granules via magnetron sputtering or the sol-gel method prior to the coating of the MPS. The HAp granules coated with the silica interlayer were fully covered by the MPS particles. An silica interlayer may offer bonding between the HAp granules and MPS coating. The adsorption of protein on the MPS-coated HAp granules was evaluated by UV-VIS spectroscopy. The adsorption capacity of protein on the HAp granules was improved by the MPS coatings on the HAp granules, and that of the HAp granules coated with the silica interlayer showed a higher protein adsorption capacity.

Abstract: The preparation of mesoporous silica compact through spark plasma sintering (SPS) and adsorption / desorption of protein onto SPS mesoporous silica (MPS) compact is reported. MPS powders, prepared using triblock copolymer, PEO₂₀PPO₇₀PEO₂₀, were compacted in carbon die and heated at 400 or 500 °C for 5 min under uniaxial pressure. The products are referred to as MPS-400 and MPS-500, respectively. The MPS sinters keep the mesoporous configuration, but the mode diameter of MPS-400 was smaller than that of MPS powders and MPS-500. The adsorbed amounts of protein on MPS-400 was higher than that on MPS-500, while the pore diameter, BET surface area, pore volume of MPS-400 are less than those of MPS-500. The interstices in MPS-500 are narrower than that in MPS-400, which may restrict the protein to penetrate through the narrow channels to reach the mesopores of MPS. The quantity of adsorbed amount of protein on MPS sinters does not depend on mesopore configuration but on the macropore configuration of the MPS sinters.

Abstract: Applications of computer and information technology are indispensable in various fields especially in the field of biology. The use of computer aided tools plays a key role in solving biological problems. The spontaneous process of molecular docking is important for finding potentially strong candidate of drug for various viruses. The binding of protein receptors with ligand molecules is essential in drug discovery process. The aim of molecular docking tools is to predict the interaction between protein and ligand. This review outlines the major tools for protein - ligand docking which in turn emphasize the importance of molecular docking in modern drug discovery process.

Abstract: The preparation of mesoporous silica coated rf-sputterd apatite / titanium substrate and protein adsorptive property is reported. Hydroxyapatite coated titanium implant has been used, and the adsorption of proteins onto implant is very important for bond formation between bone and implant. Mesoporous silica (MPS) materials have been extensively studied as carriers of bio-molecules due to their potential practical applications in medical materials. Pore diameters of 1.5 – 30 nm of the periodic mesoporous materials are close to the diameters of target molecules and high adsorbed amount of proteins onto MPS has been reported, and also enclosure of the protein in a well-defined space may help to prevent denaturation. Previously, we reported the MPS coating on the porous hydroxyapatite (HAp) ceramics obtained by dip-coating method, and by the vapor phase synthesis. Protein adsorption on the porous HAp with the MPS coatings was evaluated using UV-VIS spectrometry, and the quantity of adsorbed amount of protein was remarkably improved. In this study, the HAp deposition on Ti substrate (HAp/Ti) was carried out by rf magnetron sputtering and hydrothermal treatment, and MPS coating on HAp/Ti using LB deposition apparatus to improve the protein adsorptive property of HAp/Ti. The quantity of adsorbed protein onto the HAp /Ti was around 12 times high, and that onto the MPS/HAp/Ti was 18 times high compared to that on Ti substrate.

Abstract: Bio-inspired nanogels were prepared by ionically crosslinking sodium tripolyphosphate (TPP) and biomimetic phosphorylcholine-chitosan derivative (PCCs) which was synthesized from chitosan and cell membrane-mimicking phosphorylcholine. The physcochemical properties of PCCs/TPP nanogels were investigated by dynamic laser scattering and transmission electron microscopy, as well as their hemocompatibility were tested. Bovine serum albumin was used as a model protein to study protein adsorption, loading and releasing property of these nanogels in vitro. The results indicated that biomimetic PCCs/TPP nanogels can not only restrain the non-specific protein adsorption, improve the hemocompatibility, but also have good loading and releasing protein efficacy, which will be a promising nanocarrier for protein drug delivery.

Abstract: In the present work, we demonstrate the theoretical feasibility of basic logic gates consisting of dipole-coupled Dronpa molecules, potentially permitting the realization of nanoscale, low energy consuming and dissipating, terahertz-frequency computers and digital signal processors. The operational principle is related to an experimentally demonstrated, electric field-induced switching behavior of proteins.

Abstract: Magnesium and magnesium alloys are gaining considerable attention for use in biomedical applications due to their capability to completely resorb in the human body without noticeable side effects. For structural biomedical applications however, the resorption rate is too large. In order to decrease this rate researchers are investigating magnesium alloys with an increased corrosion resistance and/or biodegradable coatings, such as dense protein layers, which retard the resorption.In this work, we demonstrate the electrophoretic deposition of Bovine Serum Albumin (BSA) directly onto pure magnesium substrates using unbalanced alternating fields (AC-EPD). The effect of the obtained coatings on the corrosion behavior of the substrates was evaluated by potentiodynamic polarization. The results show that an albumin layer deposited by AC-EPD from a 50/50 ethanol/H₂O medium significantly reduces the corrosion rate.

Abstract: The study examines the efficiency of nutrients removal by a locally isolatedmicroalgae strain from Palm Oil Mill Effluent (POME) treatment pond, Characium sp. Theexperiment was conducted in laboratory conditions at room temperature for 20 days. Sampleswere taken at a two-day interval for dry weight, Chemical Oxygen Demand (COD), andnutrient removal analysis as well as carotenoid, protein and lipid content. The study showedthat the COD level of POME was reduced by 45.41%. Characium sp successfully removed90.35% of ammoniacal nitrogen, 86.9% of ammonia, 87% of ammonium and 88.6% of totalnitrogen content. This species was also found to remove up to 99.1% of phosphate contentand 99.5% of phosphorus. Characium sp produced 0.78 mg/L of carotenoid, 15.24 mg/L ofprotein and 18.43 mg/L of lipid by the end of the 20-day study period.