Ninhydrin Lab

PRACTICAL 1 POST-LAB QUESTIONS
Part 1
4. Line of best fit, it decreases twists that a/some deviant point(s) could bring about due to the errors that may have happened during the experimental process. This is better than connecting all the data points and assuming all the points collected from the experiment are totally accurate as there are still chances for the experimental errors to happen throughout the experiment process. 5. Yes, if the absorbance of the sample appeared to be outside the linear range, it is still possible to determine the protein concentration of the solution from the standard curve by diluting the solution. Dilution itself is a process of lessening a solute’s concentration in a solution. In this experiment, dilution can be done by reducing the amount of protein solution from 1.0 ml to 0.2 ml. Without the process of dilution, the absorbance will end up being an extrapolated value causing the result to be unreliable.

Part 2
6.
We can use Ninhydrin solution instead of biuret reagent. While using biuret reagent in performing this experiment does not require any heating up, using ninhydrin solution will need a process of heating up. After the process of heating up, violet-colored complex will develop in the presence of proteins, similar to biuret reagent, as ninhydrin solution reacts with amino acids which are present in the proteins. We can also repeat the experiment for several times in order to get a more constant result to determine the protein concentration in the solution. Taking the average concentration from several experiments will make the result more reliable and