1.0 Purpose
1.1 To establish a formal procedure
for Microbiological media preparation.
2.0 Scope
2.1 This procedure is applicable for preparation and storage of media used for
Microbiological analysis in Microbiology Laboratory.
3.0 Responsibilities
3.1
Microbiologists
perform the activity as per procedures.
3.2
Lab
attendant helps the microbiologists.
3.3 Head of Quality Control/In-Charge is responsible for effective implementation of the
procedure.
3.4 Head of QA is responsible for SOP compliance.
4.0 Abbreviations and Definitions
|
Keyword |
Definition |
|
Media |
A
growth medium or culture medium is a liquid or gel designed
to support the growth of microorganisms. |
|
Batch |
A batch
refers to all tubes, plates or containers of media prepared at the same time,
on the same date, sterilized on the same date and/or with the same lot number
when ordered pre-prepared from a manufacturer. |
|
Sterilization |
Complete
destruction of all-forms of unwanted microbial life. |
5.0
Materials
and Equipment
5.1
Precision
Balance
5.2
Water
Bath
5.3
Autoclave
5.4
pH
meter
5.5 Glassware (flasks (Erlenmeyer flasks), beakers, graduated cylinders, pipettes, petri
dishes, media bottles, funnels, test tubes, and volumetric flasks,etc.)
5.6 Spatula
6.0
Precaution
/ Health and Safety Considerations
6.1
Use
Water for Injection for media preparation.
6.2 Use
a calibrated balance with the appropriate weight range for accurate weighing of
dehydrated media or media constituents.
6.3 Use clean weighing containers and tools (such as spatulas) to prevent foreign
substances that may alter the composition of the finished media from entering the
formulation.
6.4 Thoroughly
dissolve dehydrated media in water prior to sterilization.
6.5 Do not overheat media as all culture media, to a greater or lesser extent, are heat
sensitive. Darkening of media is a general indication of overheating.
6.6 Perform re-melting of an original container of solid media only once to avoid media
overheating or potential contamination. Perform re-melting of media in a heated
water bath.
6.7 Do not hold the molten agar medium in a water bath at a temperature of 45° C to 50° C
for not more than 8 hours.
6.8
Follow
biological hazard safety procedures for disposal of media.
7.0 Procedure
7.1
Receipt of Media
7.1.1 Upon
receipt, log in dehydrated media arriving at the laboratory for the following
information at a minimum.
7.1.1.1
Name
of media, manufacturer and lot number
7.1.1.2
Quantity
Received (i.e., size and number of containers)
7.1.1.3
Date
Received
7.1.1.4
Expiration
Date
7.1.1.5
Storage
Locations
7.1.1.6
Date
Opened
7.1.2 Upon receipt, write the date received and initials on each container. Upon opening the
container(s), record the date and initials on the container. Transfer information recorded on
any outside boxes or covers to each container when
opened.
7.1.3 Inspect each lot of dehydrated media upon opening for overall appearance, clarity, color and
consistency, completeness of information on the label, and that the container was properly sealed
upon arrival, and
record the information.
7.1.4 Do not use media if any of the following conditions are observed upon receipt: color of
media/reagent is not uniform, consistency of media/reagent is not uniform, label information is
incorrect, the seal is not intact, or the amount received does not match the amount described on the
manufacturer’s label.
7.2
Storage and Disposal of Dehydrated Media
7.2.1
Store media and reagents properly according to
manufacturer’s instructions.
7.2.2 Store Media in a designated area away from areas where potential contamination and/or
damage could occur (e.g., exposure to sunlight,
moisture, etc.).
7.2.3
Use older stock of media first.
7.2.4
Dispose of media after use or upon expiration date
whichever is earlier.
7.2.5 Dispose of media properly. Dispose of unused, expired dehydrated media into a trash
receptacle unless otherwise indicated on the
manufacturer’s label.
7.2.6
Upon disposal of media and reagents, record the date of
disposal and analyst initials.
7.3
Preparation of Media
7.3.1 Follow media manufacturer’s instructions for preparing and sterilizing dehydrated media. Refer
to media label for instruction(s) because different media types may have different preparation
requirements (e.g.,
heating, additives, and pH adjustment).
7.3.2
Record the following
information at a minimum during media preparation:
7.3.2.1
Name
of media.
7.3.2.2
Unique
batch number traceable to lot number.
7.3.2.3
Date
prepared.
7.3.2.4
Amount
prepared (liquid volume and weight of media).
7.3.2.5
pH
of media before sterilization and pH adjustment (if applicable).
7.3.2.6
pH
of media after sterilization (if applicable).
7.3.2.7
Analyst
Initials.
7.3.3
Use abbreviations for media names according to individual
laboratory procedures.
7.3.4 Perform sterilization of media by autoclaving at 121° C for 15 minutes. Maintain sterilization
records for each batch of media prepared.
7.3.5 Check the pH of media before and after sterilization. If applicable, adjust pH with filter sterilized
acids and/or bases.
7.4
Storage of Media
7.4.1 Store prepared media under validated conditions. Do not store agar at or below 0° C, as
freezing could damage the gel structure.
7.4.2 Protect stored media from exposure to light and excessive temperature. Before prolonged
storage, place agar plates into a sealed package
or container to retard moisture loss.
8.0 Reference Document
8.1
WHO Guidelines, volume 2, second
edition.
9.0 Annexure
9.1
No Appreciable
10.0 Revision History
|
Revision
No. |
Brief reason for the revision |
Effective Date |
Remarks |
|
01 |
New |
|
|
11.0 Training
11.1 Head of Quality Control or his/her
nominee shall give the SOP training before effective date.
