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Chemistry Assignment (Solved)

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Added on  2020-04-15

Chemistry Assignment (Solved)

   Added on 2020-04-15

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Running head: CHEMISTRY 0CHEMISTRYName of StudentInstitution Affiliation
Chemistry Assignment (Solved)_1
CHEMISTRY 2Introduction It is very difficult to study complex natural cell membrane due to their native states. Lipids with the simpler model system are hence admirable for studying biomolecule interaction as well as the particular role of the component of the membrane. The suitable choice of the model will highly depend on the method employed for the scrutiny[ CITATION Ang15 \l 1033 ]. Every model selected will have both disadvantage and advantage. The bilayers of lipids can be made on the solid support through using multiple methods including Langmuir-Blodgett (LB) and LS (Langmuir –Scaefer ). This method can be done in situ but LS and LB methods will need deposition of just a monolayer at a time by the help of Langmuir fil balance. This method is preferred for the bilayer deposition having a specific and controlled asymmetric leaflet composition. The most common method of preparing model cellular membrane is (DIBB) Droplet Interface Bilayer method. In this technique, the lipid bilayer is made from two water droplets which are submerged in oil and also coated with a monolayer of lipids. This can be either control, asymmetric or symmetric each droplet composition bilayer tailoring can be realized[ CITATION Jac12 \l 1033 ]. In addition, the solution on either side of the membrane is able to be controlled permitting for studies of the interactions in the membrane and specific bimolecular. This technique was employed recently to reconstitute bilayer of lipids from the totalextract of model cell membrane known as Escharia coli. SURFACE SENSITIVE METHODS TO STUDYSUPPORTED LIPID BILAYERS AND MOLECULARINTERACTIONS WITH THEM
Chemistry Assignment (Solved)_2
CHEMISTRY 31.Quartz crystal microbalance with dissipation. The inherent properties of the piezoelectric quartz can be keenly analyzed using QCM-D to trigger oscillation in the sensor, this will respond by deforming immediately when an external voltage is subjected to it[ CITATION Bud12 \l 1033 ]. The standing shear waves will be developed inthe two gold electrodes due to the application of the alternating voltage. The shear wave will decay into the liquid having the characteristic length of decay. This length is always taken as 250nm, this for the crystal which is immersed in a pure water hence, this will give a perfect range of detection for the QCM-D. A solvent will be identified as a mass which is coupled with a mean thickness conforming to ΔῥL. Where ῥL is taken as the density of the liquid. The length of decay will vary with the following equation[ CITATION Gün11 \l 1033 ]. nL; where nL is the absolute density of the liquid. Hence, if the solvent is exchanged with another one having higher viscosity, it will trigger an increase in the mean thickness detected by the crystal. The principle for the operation of QCM.D is based on the relationship between the change in frequency and the change in mass of sensor crystal. For such setup, if a change in mass is taken as Δm and change in frequency is taken as Δf, then from the simple Sauerbrey relationship Δm=-C* Δf/n. where C is the material specific Saurbray constant which is given as C=tg*ῥq/f0 and n is the harmonic number. Tq is the thickness of the quartz while ῥq is the density of the quartz[ CITATION Vin14 \l 1033 ]. QCM-D basically records the wet adsorbed and not the dry ones since other optical techniques like ellipsometry, reflectometry and surface plasmon will do. This can be evident as an asset of the QCM-D method because it includes a tool needed for complementary info for the
Chemistry Assignment (Solved)_3

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