Unit 3 Macromolecules

Macromolecules are large complex molecules with molecular weights exceeding 10,000 Daltons they are a protein, nucleic acid or polysaccharide in nature (Nelson and Cox, 2013). To understand the structure of a protein, one needs to isolate in pure form. A protein can also be determined by the molecular weight during the purification process. The aim of this experiment is to separate the macromolecules of the three proteins Blue dextran, Haemoglobin and Cytochrome c, based on their differences in molecular weight (MWt) (Biochemistry Practical Manual, 2018).
The size exclusion chromatography (known as gel-filtration) is used to separate the proteins in order of size. A column packed with Sephadex porous gel particles, which consists of cross-linked polymer beads. There is maximum pore size set throughout the gel particle and if the proteins do not match the pore size then the largest proteins will feed through the quickest followed by the intermediate and then the smallest (Nelson and Cox, 2013). …show more content…
Many types of volumes were calculated and the equation was then used Ve = Vo + Kd.Vi finding the distribution coefficient (Kd), by rearranging the formula. From the calibration curve of Log molecular weights versus Kd for many proteins of known molecular weight. A formula is derived. y = -1.8499x + 5.0876 Kd is substituted into the equation at x value. To find the molecular weight is the reverse log of this equation value. (Biochemistry Practical Manual,