SOP Title: Preparation and Handling of Laboratory Reagents
- Objective:
To lay down the procedure for Preparation and Handling of Laboratory Reagents in Quality
Control Department.
- Scope:
This procedure is applicable for Preparation and Handling of Laboratory Reagents used for
Analysis in Quality Control Department.
- Responsibility:
- Quality Control Department: To prepare and review the SOP. To follow the procedures laid down for Preparation and Handling of Laboratory Reagents in Quality Control Department as per this SOP.
- Quality Assurance Department: To review and approve the SOP and Annexure.
- Accountability:
Head Quality Control Department, Head Quality Assurance Department
- Procedure:
| 5.1 | Precautions: | ||
| 5.1.1 | Always use personal protective equipments such as Hand gloves, nose masks, and goggles while preparing reagents. | QC Associate | |
| 5.1.2 | Strictly follow the precautions, warning mentioned on chemical/reagent bottles or refer Material Safety Data Sheets (MSDS) which provide information concerning the safe handling of chemicals, their storage, hazards, first aid and disposal. | ||
| 5.1.3 | Do not draw any liquid into pipette by mouth as the chemical/solvent in the pipette may enter into the mouth. Use rubber bulb or other pipetting aids. | ||
| 5.1.4 | While preparing acid solutions, always add acid to water. Do not add water to acid as this reaction may produce significant heat. | ||
| 5.1.5 | All reagents/indicators/standard solutions shall be stored in tightly-closed containers. | ||
| 5.2 | Procedure for preparation of general reagents/indicators/standard solutions: | ||
| 5.2.1 | Use analytical grade chemicals/solvents and prepare reagents as per Standard Testing Procedure or Pharmacopoeia. | ||
| 5.2.2 | As per requirement, Reagent, indicators, limit test standard solutions should be prepared by accurately weighing a suitable quantity specified in individual official monograph (IP, BP, USP or STP) and dissolving it in purified water or prescribed solvents to produce a specific concentration. | ||
| 5.2.3 | Storage of solution is as per Pharmacopoeia /STP requirement. | ||
| 5.2.4 | Store all the solutions in cleaned dry borosilicate glass bottles at room temperature or as specified in respective STP or Pharmacopoeia. | ||
| 5.2.5 | Solutions which are light sensitive shall be preserved in amber coloured borosilicate glass bottles. | ||
| 5.2.6 | Record all the preparation details in “Reagent Preparation Register” as per Annexure. | ||
| 5.2.7 | Allocate reference number for all the general reagents/indicators prepared as ‘GR/XXX/PP/YY-NN’.
Where ‘GR’ stands for ‘General Reagent’. ‘XXX’ stands for ‘Reagent Number’. ‘PP’ stands for ‘Reference Pharmacopoeia i.e. IP, BP, USP, EP, ‘YY’ stands for ‘Last two digits of the current year’. ‘NN’ stands for ‘Serial number of preparation i.e. 01, 02 and so on’. |
||
| 5.2.8 | Example: If Ammonia solution which has reagent number as GR/022/BP is prepared as per BP for the first time in the year 2024, then the reference number shall be GR/022/BP/24-01.
If the same solution is prepared for second time in the year 2024, then the reference number shall be GR/022/BP/24-02. |
||
| 5.2.9 | If the reagent preparation method is same in two or more Pharmacopoeias, then the Reference Pharmacopoeia for the reagent number shall be denoted by first letter of Pharmacopoeias used.
Example: If the reagent preparation method is same in IP, BP and USP, then the Reference Pharmacopoeia for allocating the reagent number shall be ‘IBU’ where ‘I’ stands for ‘IP’, ‘B’ stands for ‘BP’, ‘U’ stands for ‘USP’. |
||
| 5.2.10 | “Reagent Preparation Register” should have the “Index sheet” for reagents/indicators/standard solutions present with reagent number as GR/001/IP, GR/002/BP and so on as per define Annexure. | ||
| 5.2.11 | All reagents/indicators/standard solutions bottles shall be labelled as “Reagent Solution” indicating the name, concentration of the solution, date of preparation, signature of the person who prepared it, validity and storage conditions as per define in Annexure. | ||
| 5.2.12 | Supervisor should verify that all the reagents/indicators/standard solutions are prepared as per STP or Pharmacopoeia and check the “Reagent Preparation Register”. | ||
| 5.2.13 | All the reagents/indicators/standard solutions shall be kept on the racks of the working table provided in wet chemistry area. | ||
| 5.2.14 | Unless otherwise specified, all the reagent solutions should be used within 3 months from the date of preparation. | ||
| 5.2.15 | Example: If Sodium hydroxide solution is prepared on 01/05/24, then the date of preparation shall be 01/05/24 and the validity shall be 31/07/24. | ||
| 5.2.16 | Unless otherwise specified, all the limit test solutions, indicators and standard solutions should be used within one month from the date of preparation. | ||
| 5.2.17 | Example: If Phenolphthalein solution is prepared on 20/04/24, then the date of preparation shall be 20/04/24 and the validity shall be 19/05/24. | ||
| 5.2.18 | If any STP or Pharmacopoeia says ‘Freshly prepared’ then those reagents should be prepared on the day of use and discarded on completion of analysis or used within 24 hours. | ||
| 5.2.19 | All solutions that show evidence of deterioration, e.g. sedimentation, discoloration or crystallization, shall be discarded regardless of validity. | ||
| 5.2.20 | All the reagents/indicators/standard solutions shall be destroyed as per SOP “Destruction of Laboratory waste”. | ||
| Examples of Reagent preparations: | |||
| 5.2.21 | 10 % w/v solution of Sodium Hydroxide: Dissolve 10 gram of sodium hydroxide in purified water and dilute it to 100 ml with purified water. | ||
| 5.2.22 | 5% v/v solution of Acetic acid: Dilute 5 ml of acetic acid to 100 ml with purified water. | ||
| 5.2.23 | Dilute Sulphuric acid: Add 5.5 ml of sulphuric acid to 60 ml of water, allow to cool and add sufficient water to produce 100 ml. | ||
| 5.2.24 | 2 M Sulphuric acid: When solutions of molarity ‘x’ M are required, they should be prepared by carefully adding 54 X ‘x’ ml of sulphuric acid to an equal volume of water and diluting to 1000 ml with water. Where ‘x’ is the required molarity. 98.07 is the molecular weight of sulphuric acid and 1.84 gm/ml is the density of sulphuric acid. | ||
| 5.2.25 | Aluminum Standard Solution (10 ppm Al): Dilute 1 ml of a 1.39 % w/v solution of aluminum nitrate to 100 volumes with water. | ||
- Definitions / Abbreviations:
- Definitions :
- Reagent: Reagent is a substance or compound that is added to a system in order to bring about a chemical reaction, or added to see if a reaction occurs.
- Indicators: Indicators are reagents used to determine the specified endpoint in a chemical reaction which indicates the change in colour, to measure hydrogen-ion concentration (pH) or to indicate the desired change in pH has been effected.
- Buffer solutions: Buffer solutions are solutions that resist change in the activity of an ion on the addition of substances that are expected to change the activity of that ion.
- Carbon Dioxide-Free water: It is the purified water that has been boiled vigorously for 5 minutes or more and allowed to cool while protected from absorption of carbon dioxide from the atmosphere.
- Expression of concentrations:
Molar solutions (M): Molar solutions are solutions that contain 1 gram molecule of the compound in 1 litre of solution.
Normal solutions (N): Normal solutions are solutions that contain 1 gram equivalent weight of the compound in 1 litre of solution
Percentage weight in weight (%w/w): It expresses the number of grams of solute in 100 g of product.
Percentage weight in volume (% w/v): It expresses the number of grams of solute in 100 ml of product.
Percentage volume in volume (% v/v): It expresses the number of milliliters of solute in 100 ml of product.
Percentage volume in weight (% v/w): It expresses the number of milliliters of solute in 100 g of product.
Parts per million (ppm): “Parts per Million” is a way to quantify very low concentrations of substances. For example, 1 ppm is equivalent to 1 milligram of solute per litre of liquid (abbreviated as mg/L). 1 milligram of solute per millilitre of liquid (abbreviated as mg/ml).
1 mg/ml = 1000 ppm
- Abbreviations :
| Abbreviation | Expansion |
| SOP | Standard Operating Procedure |
| QC | Quality Control |
| QA | Quality Assurance |
| pH | Power of Hydrogen |
| MSDS | Material Safety Data Sheet |
| mg | milligram |
| ml | milliliter |
| e.g. | example |
| IP | Indian Pharmacopeia |
| BP | British Pharmacopeia |
| USP | United States Pharmacopeia |
| STP | Standard Testing Procedure |
*Note – Ready to use SOP available in “DOWNLOAD” Section.