Laboratory MedNews

The diasys spectrophotometer is a brand of spectrophotometer that you can operate manually or semi-manually.  Just like any other spectrophotometer, it operates using the Beer-Lambert’s Law in which the amount of light absorbed is directly proportional to the concentration of the solution. Hence, the more colored a solution is the more concentrated it is, and the less colored a solution is, the less concentrated it is.

Steps

Step 1

Warm up the Diasys spectrophotometer for 10-15 minutes.

Step 2

Code in the number of the test using a standard list. Each substance has an assigned code.  You can modify this number if you want to.

Step 3

Enter the wavelength range and leave the second wavelength prompt blank.

Step 4

Key in the following:  if there are no choices, just type the information in the blanks provided.

1. sipping volume if you are to use the sipping method
2. Temperature for test
3. Units to use
4. Time of incubation
5. Intervals between readings
6. The standard value
7. choice of display values whether absorbance of concentration values
8. highest and lower limits of the substance

Step 5

The Diasys spectrophotometer will prompt you to aspirate water.  Make use of distilled water.

Step 6

The Diasys spectrophotometer will prompt you to read your sample/s.  The machine will blip after every reading.   You could use the cuvette for cell well readings.

Step 7

Record your readings. If they are in absorbance, then you have to compute for the unknown concentration. If they are in concentrations, then you should record and report them accurately.  You can program the machine for automatic printed results also.

Step 8

Terminate your procedure by cleaning the Diasys spectrophotometer of any dust, liquid or dirt. Remove all materials from the machine.  Cover properly and unplug.

Warnings:

1. Warm the Diasys spectrophotometer properly to stabilize it and allow reliable readings.
2. If you decide to use a cuvette, wipe it with soft tissue paper or cloth to prevent smudges and dirt in interfering with the readings.
3. When washing your cuvettes, do not brush them, as scratches would reflect light, making the readings inaccurate.
4. During the readings, remove the solution from the sipping tube as soon as you hear the blip, so air could be aspirated, preventing contamination through the overflowing of one unknown solution to another.
5. Key in the correct information needed to obtain accurate results.
6. Record your results immediately.

You should keep the Diasys spectrophotometer in tiptop shape by protecting it from dirt and contamination.  It should also be calibrated every year.