Alternative procedure, in case Peltier accessory is not there

1. 1.  Prepare sufficient volume (at least 15 ml ) of the DNA sample in the given buffer so as to obtain an absorbance between 0.1 – 0.4.

2.  Take fourteen 1.5 ml microfuge tubes and label them 1 – 14.

3.  Add 1 ml of DNA solution into each of the microfuge tubes.

4.  Tightly seal all the tubes with parafilm.

5.  Label the three water baths as I, II, and III.

6.  We shall be measuring absorbance at 20, 30, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, and 95 degrees Celsius i.e. at 14 different temperatures.

7.  Set water baths I, II, and III at 20 °C, 30 °C, and 40 °C temperatures, respectively.

8.  Place the tubes 1, 2, and 3 in water baths I, II, and III, respectively and incubate at least for 10 minutes.

9.  Take tube 1 out and immediately measure its absorbance at 260 nm against the buffer blank.

10.  Set the water bath I to 45 °C and place tube 4 in it once the specified temperature is achieved.

11.  Meanwhile, take out tube 2 and measure its absorbance.

12.  Set the water bath II to 50 °C and place tube 5 in it once the specified temperature is achieved.

13.  Meanwhile, take out tube 3 and measure its absorbance.

14.  Set the water bath III to 55 °C and place tube 6 in it once the specified temperature is achieved.

15.  This cycle is to be followed until the absorbance is recorded for all the 14 tubes.

16.  Record the measurements in the observation table shown below.