Dilution Calculation Explained

Understanding Dilution Factor Calculation

Dilution factor (D.F.) is an important concept in laboratory settings, particularly in sample preparation and analysis. It represents the ratio of the volume of the original sample to the final volume after dilution.

Calculating Dilution Factor

When dealing with dilutions, the formula for Dilution factor is straightforward: D.F = 1/dilution ratio. For example, if the dilution of a sample is 1/8, the dilution factor would be 1/(1/8) = 8.

Practical Examples

Let's consider a scenario where you want to make a 1/18 dilution of a sample. If you use 7 ml of the sample, the calculation would be as follows: D.F = 1/(1/18) = 18. The final solution volume can be determined by multiplying the volume from the stock solution by the dilution factor, resulting in 7 ml x 18 = 126 ml. Therefore, you would need 119 ml of diluent to make the 1/18 dilution of the 7 ml stock solution.

Furthermore, in a three-step serial dilution with dilutions of 1/6, 1/2, and 1/10, the final dilution factor can be obtained by multiplying all individual dilution factors together. In this case, the final dilution factor would be 1/6 x 1/2 x 1/10 = 1/120 or D.F = 120.