DATE: 29TH September, 2011.
FORM CLASS: L6 3
TITLE: Quantitative Glucose Test
AIM: To determine the amount of glucose in three unknown samples namely A, B and C INTRODUCTION:
Biological molecules are held together by covalent bonds, hydrogen bonds among others bonds in various ways to produce large molecules called macromolecules. Simple organic compounds and macromolecules molecules vary in structure and can be distinguished by their functional groups. Molecules of a certain class have similar chemical properties because they have the same functional group. A chemical test that is sensitive to that group can be used to identify molecules that are in that class. There are also tests which measure the quantity of the particular biological molecule present in the substance. This was done so that one can be mindful of the quantities of certain biological molecules entering the body. This awareness can prevent and control diseases such as diabetes mellitus which is a condition where blood sugar level is not controlled correctly and affected people take insulin to help to control their glucose levels and test their blood to determine the level of glucose in it. There are a variety of different ways in which blood glucose level can be measured. It is often important to measure the concentration of glucose in a solution. In this experiment a variety of solutions will be tested for the glucose concentration of known value and a graph, drawn to show the results. This type of graph is known as a Standard Curve. This graph will then be used to estimate the glucose concentration in an unknown solution. This is the method which was used in hospital labs to measure the glucose level in blood samples. Glucose (C6H12O6) is a monosaccharide reducing sugar. In this reaction the glucose readily donates electrons which are accepted by the permanganate causing it to change colour. The time taken for the pink colour of the potassium permanganate to disappear once the glucose solution has been added will be measured. MATERIALS/APPRATUS:
MATERIALS: six (6) controlled solutions containing 90%, 80%, 70%, 60%, 50%, 40% glucose, three (3) samples A, B and C, sulphuric acid, potassium permanganate, water, APPARATUS: six (6) boiling tubes, boiling tube stand, stop watch, nine (9) beakers, measuring cylinder, 5cm syringe, 1cm syringe, two (2) glass rods, tape, white paper PROCEDURE:
Firstly six controlled samples were tested by pouring 10cm3 (ten centimeters cubed) of the 90% glucose into the measuring cylinder then placing it into the boiling tube, next 5cm3 (five centimeters cubed) of the sulphuric acid was measured with the syringe and added to the control of 90% glucose in the boiling tube the timer was then set and 1cm3 (one centimeter cubed) of potassium permanganate was measured and was simultaneously added while the timer was started. The mixture was then stirred with a glass rod until it was colourless to verify this; a piece of white paper was placed behind the boiling tube to confirm the transparency the time the mixture took to become transparent was then recorded. This procedure was repeated for the rest of control samples that is 80%, 70%, 60%, 50%, and 40% and was done twice for accuracy the both times recorded were then averaged. Finally when all of the results of the controls were recorded the test was repeated on the samples A, B and C and compared to that of the controls to obtain how much sugar was present within the samples. RESULTS:
TABLE 2.0: TABLE SHOWING THE TIMES RECORDED DURING THE CONTROL TESTS AND THE AVERAGE OF THE TWO TIMES RECORDED GLUCOSE CONTROL PERCENTTEST1 (seconds)TEST2 (seconds)CALCULATIONSAVERAGE 90%194 198(194+198)/2196
TABLE 2.1: TABLE SHOWING THE TIMES RECORDED DURING THE SAMPLE TESTS AT A PARTICULAR LEVEL OF...