# Ingredients for Preparing Antiseptics and Disinfectants

In Preparations of Antiseptics and Disinfectants we use Ingredients, Ingredients are the constituents or substances that form a mixture.

In this article you will learn:

- Ingredients used to prepare antiseptics and disinfectants
- The proportion of antiseptic and disinfectant with distilled water
- Calculation of the proportion of antiseptics and disinfectants to make different total volumes.

# Ingredients used to prepare antiseptics and disinfectants

**1. Jik® and water**

**image of jik solution**

- The two main ingredients needed to prepare 10% bleach solution are Jik® and water.
- The proportion of these two ingredients is 10 parts concentrated bleach (Jik), and 90 parts water since the total parts is 100.

** 2. Stock disinfectant and water**

- The ingredient in diluted disinfectant such as Lysol® is stock disinfectant and water.
- 5%V/V Lysol® solution is 5 parts of Lysol® concentrated solution in 100 total parts including the distilled water.

**image of Lysol solution**

**3. Stock concentrated antiseptic and water**

- The ingredients in diluted antiseptic 70%V/V methylated spirit is stock concentrated antiseptic and water.
- For example, 70% methylated spirit has 70 parts of absolute methanol and 30 parts of water.

**image of 70%methylated spirit**

*Read also: Antiseptics and Disinfectants*

## The proportion of antiseptic and disinfectant with distilled water

**10% bleach (Jik):**is 10 parts of concentrated bleach solution in 100 total parts including the diluent (distilled water).- This is a volume/ volume %V/V solution since it involves measuring out volume of concentrated bleach and diluting to a total volume.

**Note:** solvent used to lower concentration of a solute in a solution, that is water.

**5% Lysol:** is 5 parts of Lysol in 100 total parts. 5 parts of Lysol® concentrated solution in 100 total parts including the diluent. This is a volume/ volume %V/V solution since it involves measuring out volume of concentrated Lysol and diluting to a total volume.

**70% methylated spirit (methanol):** is 70 parts of methylated spirit in 100 total parts. 70 parts of concentrated (absolute) methanol in 100 total parts including the diluent. This is a volume/ volume %V/V solution since it involves measuring out volume of concentrated methanol and diluting to a total volume.

### Calculation of the proportion of antiseptics and disinfectants to make different total volumes.

- Calculations are used to determine the proportion of antiseptics and disinfectants to make different total volumes.

**Calculations in preparing 100 mL of 5% Lysol®**

- 100 mL of 5% Lysol® is made from the formula 5% x 100 mL =5 mL the volume of
**Lysol®**to make the dilution. Total volume is 100 mL – 5 mL Lysol so approximately 95 mL of water is added. Actually you add water to the 5 mL of strong Lysol in a 100 mL measuring graduate cylinder until the total volume is 100 mL which is approximately 95 mL of distilled water. - To determine how to make a specific volume, multiply the final volume times the percent solution desired to calculate the volume of stock solution needed. Total volume – volume of stock = approximate volume of diluent added. So to make 200 mL of 5% Lysol solution 200mL x 5% = 200 x .05 = 10 mL Lysol added to measuring cylinder. Add remaining volume, approximately 190 mL distilled water to make 200 mL total volume.

**Calculations in preparing 5 L of 5% Lysol**

- 5 L of 5%V/V Lysol® is made from 5% x 5000mL = .05 x 5000 = 250 mL the volume of Lysol to make the dilution in a 5 L flask. 5000-250 = approximate volume of distilled water added = 4750 ml.

**Calculations in preparing 500 mL of 10% bleach.**

- How do you make 500 mL of 10% bleach? 500 mL of 10%V/V Jik® is made from 10% x 500 mL = 500 x 0.10 = 50 ml. 50 mL of concentrated Jik® is diluted with distilled water to a total volume of 500 mL in a measuring graduate cylinder. Approximately 500 –50 mL or 450 mL of distilled water is added.

**Calculations in preparing 20 mL of 70% V/V methanol antiseptic**

- 20 mL of 70%V/V methylated spirit is made from 70% x 20 mL = 0.70 x 20 = 14 mL, the volume of absolute methanol needed. 14 mL of methanol is diluted to a final volume of 20 mL by adding 20-14 or 6 mL of distilled water.

**Calculations in preparing 250 mL of 70% V/V methanol antiseptic**

- 250 mL of 70% V/V methanol antiseptic is made from 250 x 70% = 250 x 0.7 = 175 mL of absolute methanol is diluted to a total volume of 250 mL with distilled water.

**Something to note:**

**main ingredients needed to prepare 10% bleach solution**

- stock bleach solution and distilled water are needed to prepare 10% bleach. And proportion of these two main ingredients needed to prepare 10% bleach solution Are 10 parts of stock bleach and distilled water to make 100 total parts.
- 10 mL of stock bleach + 90 mL distilled water = 10/100 or 10%.

**References**

*F.J. Baker, R.E. Silverton (2001): Introduction to Medical Laboratory Technology, 7thEdition, Oxford University Press; Oxford, England.**Monica Cheesbrough (1981): Medical Laboratory Manual for Tropical Countries Volume I, 2nd Edition Butterworth & Co. (Publishers) Ltd;**Monica Cheesbrough (2002): District Laboratory Practice in Tropical Countries Part 1 & 2, Cambridge University Press; Cambridge, England.*