The basic principle of dilution in biology is to reduce the concentration of a sample by adding a known amount of solvent. This results in a more manageable concentration for testing or experimentation. Dilution can be done by using a dilution factor, which is calculated by dividing the final concentration by the initial concentration.
The appropriate dilution factor for your sample will depend on the initial concentration and the desired final concentration. To determine the dilution factor, divide the final concentration by the initial concentration. For example, if you want a final concentration of 1:10 and your initial concentration is 1:100, the dilution factor would be 1:10 ÷ 1:100 = 1/10 or 0.1.
The best method for preparing dilutions in biology is through serial dilution. This involves diluting a sample multiple times in a stepwise manner, which ensures a more accurate and precise result. Each dilution is done using a new pipette to avoid contamination and ensure accurate measurements.
To properly mix your diluted sample, gently vortex or invert the tube multiple times. This ensures that the sample is evenly mixed and the dilution is consistent throughout. It is important to avoid vigorous mixing, as this can introduce air bubbles and affect the accuracy of the dilution.
Some common mistakes to avoid when making dilutions in biology include not properly labeling the dilution tubes, using the wrong dilution factor, not using a new pipette for each dilution, and not mixing the diluted sample properly. It is also important to use accurate and precise measurement techniques, such as using calibrated pipettes, to ensure the accuracy of the dilution.