Analytical Quality Assurance: Peracetic Acid Standard

Introduction

The objective of analytical quality assurance (AQA) is to ensure correct and precise test results. AQA is recommended before each measurement series or in case a test result deviates from the expected value. It is used to ensure the measuring system works properly and that no handling mistakes are made.
The peracetic acid standard solution can be used after dilution to perform AQA for the test systems listed below in the article.

A certificate of analysis is provided for each batch and can be downloaded online on the product page of the test as well as a certificate of quality, where all batches are taken into account. Nevertheless, it is recommended to determine the performance characteristic yourself so that all specific factors that may impact the performance (test reagents, measurement device, handling) are considered in the characteristic data.

This application describes the preparation of a peracetic acid standard solution of concentration 1000 mg/L, which can be used for analytical quality assurance (AQA).

Experimental

Reagents, Instruments, and Materials

• Deionized water
• Sodium hydroxide solution 0.1 mol/L (1.09141)
• Peracetic acid solution 38 40% (1.07222)
• Cerium (IV) sulfate solution 0.1 mol/L (1.09092)
• Sodium thiosulfate solution 0.1 mol/L (1.09147)
• Sulfuric acid, 25% (1.00716)
• Ferroin indicator solution (1.09161)
• Potassium iodide, for analysis (1.05043)
• Starch solution, for analysis (1.01252)

Preparation of standard solution

• 450 mL deionized water
• 4.0 mL sodium hydroxide solution 0.1 mol/L (1.09141)
• 1.25 mL of peracetic acid solution 38 - 40% (1.07222)
• adjust to pH 3.5 with sodium hydroxide solution 0.1 mol/L (1.09141)

Transfer this solution into a 500 mL-volumetric flask and fill it off with deionized water. The exact concentration should be determined by titration with cerium (IV) sulfate solution (1.09092) and sodium thiosulfate solution 0.1 mol/L (1.09147).

Analysis of standard solution

• Transfer 30.0 mL of the standard solution into a 300 mL Erlenmeyer flask with a volumetric pipette.
• Add 20 mL deionized water, 5 mL sulfuric acid 10% (prepared from 1.00716), and 3 drops of Ferroin indicator solution (1.09161).
• Then titrate the above-prepared solution, immediately with cerium (IV) sulfate solution (1.09092) until the blue color changes to orange. This titration detects the concentration of peroxide (consumption: ca. 1 mL).

Admix the titrated sample with 0.5 – 1.0 g potassium iodide (1.05043) and 5 mL starch solution 5 g/L (prepared from 1.01252). Titrate the released iodine with sodium thiosulfate solution 0.1 mol/L (1.09147) from violet-brown to orange color. This titration detects the concentration of peracetic acid (consumption: ca. 8 mL).
Both titrations should be performed quickly one after another. The total titration should be performed within 10 minutes.

Calculation:

c_PAA [mg/L] = V_Thiosulfate[mL] * 126.75

For use with the following tests

Product. No.	Graduation/Measurement range (mg/L Peracetic Acid)	Product Description
MQuant® Test Strips
1.10084	5 – 10 – 20 – 30 – 50	MQuant® Peracetic Acid Test
1.17976	20 – 40 – 80 – 120 – 160	MQuant® Peracetic Acid Test
1.10001	100 – 150 – 200 – 250 – 300 – 400 – 500	MQuant® Peracetic Acid Test
1.17922	500 – 1,000 – 1,500 – 2,000*	MQuant® Peracetic Acid Test
Reflectoquant® Test Strips
1.16975	1.0 – 22.5	Reflectoquant® Peracetic Acid Test
1.17956	20 – 100	Reflectoquant® Peracetic Acid Test
1.16976	75 – 400	Reflectoquant® Peracetic Acid Test

* No dilution of the standard necessary

Conclusion

The standard solution of peracetic acid with a concentration of 1000 mg/L can be used for analytical quality assurance (AQA) purposes. By performing an AQA prior to each measurement it can be secured that the system in use works properly, and it prevents the user from making mistakes.