Professional quality solutions are possible when high quality and fresh chemicals and solvents are used, and meticulous procedures are followed.

Preparation and Assigning Shelf Life to Reagents & Volumetric Solutions of the reagents used in science are in the form of solutions which need to be purchased or prepared.

Purpose:-

To lay down a procedure for the Preparation and Assigning Shelf Life to Reagents & Volumetric Solutions of shelf life to volumetric solutions and laboratory reagents used for chemical analysis.

Scope of Preparation and Assigning Shelf Life to

Reagents & Volumetric Solutions:-

This SOP is applicable to all laboratory reagents and volumetric solutions used in analytical work for Preparation and Assigning Shelf Life to Reagents & Volumetric Solutions.

Responsibilities:-

• Lab. Assistant
• Officer QC
• Sr. Officer QC
• Microbiologist
• Quality Control Manager

Definitions:-

What is Shelf Life: The shelf-life of a reagent is the time at which it remains within an approved specification after preparation?

What is laboratory Reagent: A substance used in a chemical reaction to detect, measure, examine, or produce other substances.

What is Volumetric Solution: A volumetric solution is one which contains a specific quantity of solute per stated unit of volume.

For many purposes, the exact value of concentration is not critical in other cases of the concentration of the solution and its method of preparation must be as accurate as possible.

Preparation and Assigning Shelf Life to Reagents & Volumetric Solutions is the Laboratory Solution Preparation reference section is designed for both the novice and experienced solution maker. It provides valuable information on the basic concepts of preparing solutions and instructions for preparing most solutions required in the high school science laboratory.

Flow Chart:

Chapter No. Process Flow Chart

1. All solid & liquid chemicals and solvents used for the preparation of laboratory reagents and volumetric solutions shall be of AR Grade.
2. Expiration Date for the solid AR Grade Chemicals and aqueous acids shall not exceed five years from the date of receipt unless otherwise specified by the manufacturer & Expiration Date for the organic solvents (AR Grade) shall not exceed three years from the date of receipt unless otherwise specified by the manufacturer.
3. A storage life of 03 months should generally be adopted for all laboratory reagents or indicators unless otherwise specified.
4. A storage life of 01 months should generally be adopted for all volumetric solutions unless otherwise specified in the individual monograph
5. To assess the stability of a laboratory reagent QC officer will compare the results obtained by using a standard solution prepared by using a freshly prepared laboratory reagent with older preparation.
   6. Description/Procedure:

General Requirements

1. All chemicals and solvents used for the preparation of laboratory reagents and volumetric solutions shall be of AR Grade.
2. All laboratory reagents and volumetric solutions shall be prepared in purified water unless otherwise specified in the individual monograph.
3. Expiration Date for the solid AR Grade Chemicals and aqueous acids shall not exceed five years from the date of receipt unless otherwise specified by the manufacturer.
4. Expiration Date for the organic solvents (AR Grade) shall not exceed three years from the date of receipt unless otherwise specified by the manufacturer.
5. After the expiration date, the solid chemical (AR Grade) or organic solvent may be reassayed as per BP, USP or other specifications. Preparation and Assigning Shelf Life to Reagents & Volumetric Solutions If appropriate the expiration date may be extended for a period of 06 months.
6. Solutions used as reference standards for limit tests should be prepared immediately before use and discarded after use.
7. A storage life of 03 months should generally be adopted for all laboratory reagents or indicators unless otherwise specified.
8. Volumetric solutions of molarity less than 0.01M should be prepared immediately before use and then discarded after use. Volumetric solutions of molarity greater than 0.01M should be re-standardized monthly.
9. A storage life of 01 months should generally be adopted for all volumetric solutions unless otherwise specified in the individual monograph.
10. Store all the laboratory reagents and volumetric solutions in stoppard glass bottles (clear or amber as required) and protect them from heat and air.

Procedure

1. Officer quality control will prepare the laboratory reagents and volumetric solutions as per the requirements and enter the required information (date of preparation, ingredients weights and volume actually used, his or her initials etc.) in the log book.
2. After that he labels the laboratory reagents/volumetric solutions with following information:

• Solution / Reagent Name: ———————-
• Strength: ————
• Standardization Factor: ———————
• Date of Preparation/Standardization: ————-
• Expiry Date: ———————————-
• Lab. Reference No.: ————————–
• Signature: ———————-

1. To assess the stability of a laboratory reagent QC officer will compare the results obtained by using a standard solution prepared by using a freshly prepared laboratory reagent with older preparation.
2. All the laboratory reagents are assessed periodically for the period of 03 months in order to make sure their stability for the intended period and records of the stability are kept as reference.
3. QC officer will standardize the volumetric solution in triplicate on monthly basis and maintains its record in the log book. Strength of the volumetric solution should be with in ±10% of the specified strength.
4. Store the reagent / volumetric solutions at room temperature except those which require refrigeration to ensure the maximum shelf life.

Precautions

1. Keep the reagent bottle tightly closed after use in order to avoid exposure of contents to air and absorption of carbon dioxide and other contaminating vapors.
2. Do not pour unused portions of the reagent / volumetric solution back in to the bottles.
3. Do not insert the pipettes directly into the stock bottles which may leads to contamination.

Records:

1. Log of Laboratory Reagent Preparation
2. Log of Volumetric Solution Preparation

Reference:

International Research Papers/Procedures