Proteins are defined as the big molecule that is composed of one or more ironss of aminic acids in specific mode. Protein ‘s survey is really huge and divided into many countries such as nutrient processing and fabrication, biotechnology, biological science and largely of import in the medical specialty. In the huge surveies of proteins “ Adsorption survey of protein ” is really popular and complicated. ( 1 ) Adsorption is a surface phenomenon means it is related with interaction of any surface like – solid – solid interaction, solid – liquid interaction and liquid – liquid interaction etc.
As we mentioned earlier, Adsorption of protein is really complicated survey because here we traveling to analyze the surface assimilation of protein on to the solid surface in the H2O and protein shows turn uping and unfolding nature in the H2O. Adsorption phenomenon based on a rule that is whenever an interface formed ( 1 )
between two different stages it has a high free energy than bulk stage. So the interface becomes thermodynamically stabilized by adsorbing other substance different than the solvent molecule. But in specific, the surface assimilation of protein on to the solid surface is depend on the construction and alteration in conformation of protein, hydrophobic and hydrophilic interactions, and the charges on their surface. ( 1 )
The proteins are big amphiphatic molecules this characteristic do them per se surface active molecule and it causes a surface interaction. The chief causes for the surface interaction are conformational informations and restricted aristocracies, intermolecular forces, Lewis acid – base forces, columbic forces, hydrophobic interactions, new wave der Waals forces. ( 3,4 ) to boot intramolecular forces within the protein molecules that might do change of protein verification. The finding of extent of conformational alterations is really hard and even more its anticipation. So for finding of protein surface assimilation kinetic survey of the surface assimilation procedure is required. ( 5 )
The above graph is plotted between initial concentration and adsorbed sum of BSA onto the surface of MCC at pH 7. The antecedently mentioned surface assimilation of BSA on MCC is besides at pH 7 but the old work done with the ratio of BSA conc. and MCC conc. it was 0.036 and there is no surface assimilation at all that ‘s why in this instance the ratio is increased to 1, 2 and 3. That means merely BSA conc. has increased and MCC concentration remained same.
As the conc. of BSA increased there is good mannered surface assimilation seen. The graph shows as we increase the conc. of BSA the adsorbed sum besides increases and will organize a tableland. Higher conc. leads to higher surface assimilation because of electrostatic abhorrent forces between two protein molecules. Due to tonss and tonss of BSA conc. each molecule repels each other because of same charge on surface. But so these molecules competitively bind on the surface of MCC. Actually the surface of MCC and the surface of BSA have same charges on their surface but for BSA, the surface of MCC is different and mainly surface assimilation takes topographic point due to the hydrophobic interactions between both surfaces.
Graph 7: Initial concentration of BSA with Fractional coverage country of MCC at pH 7
The above graph plotted between initial concentration of BSA and fractional coverage of the MCC surfaces. The graph clearly shows as the concentration addition fractional coverage country besides increases. But the clip at which all surface assimilation sites are blocked or occupied by the BSA molecules the fractional coverage country remains changeless and it forms a tableland means no addition in fractional coverage country after that. An option is at that place for addition in farther fractional coverage country is Desorption.
The chief aim of this work is to analyze the surface assimilation of protein on to solid surfaces at different conditions such as pH, media, ionic strength etc. the above discussed work is at pH 6 and 7. Adsorption of protein on to the surface varies at different pH values. As earlier said this work is carried out with other pH besides that is 4 and 5. Basically the surface assimilation of protein governed by two forces hydrophobic and electrostatic interactions between protein and the solid surface.
The information obtained at pH 6 and 7 is far different than the pH 4 and 5. The pH and ionic strength affects surface assimilation on both MCC and silica surface. Another key of surface assimilation is “ Iso-electric point ” of protein ( BSA ) which is in the scope of 4.7 – 5.1 so, BSA surface assimilation occurs in between this scope. Hence, there is high surface assimilation of BSA on to MCC at pH 5. Besides at pH 4 BSA demoing a much higher surface assimilation than at pH 5. On the other manus at pH 6 and 7 there is no surface assimilation at all. This surface assimilation on to the MCC surface is governed by the electrostatic interaction.
The farther add-on of 0.09 % of Na chloride besides affects the surface assimilation of protein. It sometime supports the surface assimilation and sometime non. Because it depends on the distribution and interaction of salt ions that is, Na+ and Cl- with the both surface. So depending on the distribution of salt ions attractive force and repulsive force occurs.
On the other manus surface assimilation of BSA on silicon oxide surface occurs at all pH 4, 5 and 6. Here besides hydrophobic and electrostatic interaction supports the surface assimilation. At pH 4 and 5 surface assimilation governs by the opposite charges of both surfaces. But at pH 6 the surface assimilation assisted by the hydrophobic interaction. The farther add-on of 0.09 % of Na chloride supports the surface assimilation of BSA on to silica surface at all pH.
Study of surface assimilation at higher concentrations of BSA besides carried out. The survey shows higher surface assimilation of BSA on MCC at all 4, 5 and 6 pH this surface assimilation peculiarly assisted by the hydrophobic interactions.
Decision. . . . . . . .
Overall the two factors hydrophobic and electrostatic interactions play an of import function in the surface assimilation of BSA on to the surface of MCC and silicon oxide. These forces and the consequences obtained at different pH leads to following decision –
Adsorption of bovine serum albumen to microcrystalline cellulose was determined as map of protein concentration and pH of its aqueous solution. The maximal surface assimilation value attained at the BSA iso-electric point.
The overall surface assimilation was governed by hydrophobic and electrostatic interactions it sometimes supports the surface assimilation and sometimes non depends on the pH and ionic strength of the solution.
Adsorption of BSA on to the surface of silicon oxide is really good mannered and the surface assimilation attained at all 4, 5 and 6 pH. And the surface assimilation at 6 pH assisted by hydrophobic interaction alternatively electrostatic.
As the ratios of BSA and MCC increased up to 1, 2 and 3 the surface assimilation values were besides increased and attained at all pH. Where, the surface assimilation has non seen at pH 6 at lower concentrations of BSA.