The question would surprise all because why should the powerful almighty lie to Humans? The book of Genesis says the creation of God with the below list:
- Day 1: Light.
- Day 2: Atmosphere.
- Day 3: Dry ground & plants.
- Day 4: Sun, moon & stars.
- Day 5: Birds & sea creatures.
- Day 6: Land animals & humans.
- Day 7: The Sabbath of rest.
As the book was scrolled, could not find the creation of microbes!!! It was a known fact the wine, the fermented grape juice was present from the Biblical times. So, there is no doubt that Microbes were present from the creation days. Then why did God hide the Microbial world from our reach? Might be that God wanted Humans to explore the fascinating microbial world. He might have hidden to give the wonderful opportunity for Humans to explore the microscopic world.
The Microbial world is really fascinating and it took many centuries for Humans to unravel the hidden mysteries of God. The Microbial world has both cups of honey and cups of poison. Microbes are helpful and dreadful to Human beings like a double-edged sword!!!
In that context, while manufacturing drugs / products which are to administered to Humans, there should not be any microbes. In other words, the microbes have to be controlled in environments where drugs are manufactured.
To ensure they are absent, there are many microbiological techniques employed in pharmaceutical industry. Each technique has its own advantages and disadvantages with respect to the recovery of Microbes, sample volume, sampling time etc.
1.Settle plate exposure
Settle plates play an important part in the environmental monitoring program and for the assessment of microbial settlement at key locations within cleanrooms, particularly when situated within unidirectional airflow devices. Settle plates typically consist of Petri dishes filled with a culture medium, such as tryptone soya agar [TSA], which is a general-purpose medium. The amount of culture medium in a 90 mm diameter settle plate is typically 20–30 mL. Settle plates are exposed in aseptic filling zones, at determined monitoring locations, ideally positioned and exposed where the lids of the dishes are removed. The principle behind settle plates is that most microorganisms in air are in association with particles and settle down to the media plate.
Settle plates are typically exposed for periods of up to 4 hours. An exposure time of 4 hours is recommended in the guidance, although individual settle plates may be exposed for less than 4 hours. Thus, the results from settle plates are recorded as colonies forming units (CFU) settling per 4 hours of exposure.
2.Active air sampling
To perform active EM, an air sampler draws in a specified known volume of air, through or over a particle collection device, such as an agar plate. The culture is then placed in incubation and which will give information such as the bacterial or fungal count and the colony forming units.
3.Surface monitoring
The RODAC [Replicate Organism Detection and Counting] media plate is gently pressed onto selected surfaces to acquire surface samples. The contact plates to evaluate bacterial presence contains TSA while the contact plates to evaluate the presence of yeast and mould contains SDA. In instances where a sample is collected right after disinfection, appropriate neutralizer can be added to the agar if disinfectant residue is suspected. Contact plates are easy to handle and it is the easiest method of sample collection. However, it is not suitable for uneven surfaces. In such uneven surfaces, swab sampling can be done.
4.Personnel monitoring
For personnel monitoring 55 mm contact plates are used but for finger dab monitoring 90 mm SCDA plates can be used because 55 mm plates are small to cover five finger dabs properly on single plate. Personal Monitoring shall be done at the end of each shift during all the critical operations using RODAC plates. Personnel after being monitored will exit the aseptic area.
There are limits and frequencies fixed by different regulatory agencies. The brief sum up of the limit and frequencies is given an easy tool for reference.
Note-The images given for representation in this blog are taken from Google Images. Many thanks for Google.