In this study the effect of surface modification of mesoporous silica nanoparticles (MSNs) on its adsorption capacities and protein stability after immobilization of beta-lactoglobulin B (BLG-B) was investigated. For this purpose, non-functionalized (KIT-6) and aminopropyl-functionalized cubic Ia3d mesoporous silica ([n-PrNH2-KIT-6]) nanoparticles were used as nanoporous supports. Aminopropyl-functionalized mesoporous nanoparticles exhibited more potential candidates for BLG-B adsorption and minimum BLG leaching than non-functionalized nanoparticles. It was observed that the amount of adsorbed BLG is dependent on the initial BLG concentration for both KIT-6 and [n-PrNH2-KIT-6] mesoporous nanoparticles. Also larger amounts of BLG-B on KIT-6 was immobilized upon raising the temperature of the medium from 4 to 55 °C while such increase was undetectable in the case of immobilization of BLG-B on the [n-PrNH2-KIT-6]. At temperatures above 55 °C the amounts of adsorbed BLG on both studied nanomaterials decreased significantly. By Differential scanning calorimetry or DSC analysis the heterogeneity of the protein solution and increase in Tm may indicate that immobilization of BLG-B onto the modified KIT-6 results in higher thermal stability compared to unmodified one. The obtained results provide several crucial factors in determining the mechanism(s) of protein adsorption and stability on the nanostructured solid supports and the development of engineered nano-biomaterials for controlled drug-delivery systems and biomimetic interfaces for the immobilization of living cells.

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The importance of ionic channels is due to the passage of ions across the cell membrane which is based on electrochemical gradients. The structure of ionic channels often includes one or several central cores which makes up the pore. The direct electron transfer between the enzyme and unmodifi ed electrode is usually prohibited due to shielding of the redox active sites by the protein shells. Monte Carlo simulation have been used to investigate protein folding pathways with some success. Monte Carlo was originally developed for calculating equilibrium properties of physical systems .In calculations we optimized the geometry and defi ned Potential Energy of the nanotube structure by performing molecular mechanics calculation using MM+ force fi eld, if too large a time step is used in Monte Carlo simulation, it is possible to have a basic instability in the equations that result in a molecule blowing apart, we need small time steps to preserve integration accuracy, however in the Monte Carlo time step 50 femtoseconds (0.05ps) was appropriate. next step we calculated the Vibrational modes of the tube by applying the semi-empirical molecular orbital method. In this paper, we have studies the stability of CNT-Amino acids clusters using by semi-empirical method and investigation of vibrational frequencies and electrical properties. In the more the potential energy increases the more the conductivity of nanochannels decreases and we chose the least energy among nanotube and amino acid complexes. Also the more energy we use, the more conductivity we will have; therefore, we choose the complex which conducts the most current.

Aquaporins are membrane water channels that play critical roles in controlling the water contents of cells. These channels are widely distributed in all kingdoms of life, including bacteria, plants, and mammals. More than ten different aquaporins have been found in human body, and several diseases, such as congenital cataracts and nephrogenic diabetes insipidus, are connected to the impaired function of these channels. They form tetramers in the cell membrane, and facilitate the transport of water and, in some cases, other small solutes across the membrane. However, the water pores are completely impermeable to charged species, such as protons, a remarkable property that is critical for the conservation of membrane's electrochemical potential, but paradoxical at the same time, since protons can usually be transferred readily through water molecules. The present investigation is profound manifesting of thermodynamics characteristics of the impressive AQP4 role in biology. To clarify the majestic AQP4 role in biology, it was modeled. So we use pc-based modeling and simulation software package called HyperChem by applying four different force fields. The results of our simulations have now provided new insight into the optimal stability of AQP4.