Isolator systems Isolator Validation in pharmaceutical manufacturing technical guide

Pharma Isolator what is an Isolator

What is an Isolator in pharmaceutical manufacturing? how to do validation of Pharma Isolator 

As the name suggests, an isolator is an equipment designed to isolate a drug product during manufacturing from the external environment in the clean room. Isolators separate the drug product from the external environment and protect the drug product from getting contaminated. Drug product is contained inside an isolation system in the isolator which not only protects product contamination from the external environment but also protects from risks of personnel handling and contaminations arising from personnel movements. Contentment isolators are isolators which enable us to do processing of highly potent drug products and prevent the contamination of surrounding areas with the potent drug which otherwise could be dangerous to the environment or human. In the bottom of this article we have provided information on Pharma Isolator Validation.

What is the importance of an isolator?

Isolators provide protection to products from getting contamination from an external environment with higher number of particles thereby protecting product from microbial contamination, isolators are used in sterile dosage form manufacturing, where injectable dosage form is required to be sterile. The isolator provided with ULFA filters and the inner air quality have very low particle count below 50 Nos of particles of 0.3-micron particle size, and the viable particle count maintained inside the isolator can be very negligible; almost no viable particle count can be maintained for bacteria and fungus.

Isolators are used in manufacturing of highly potent molecules which if get into an external environment pose risk to humans. Such isolators are called as contentment isolators. Below also information is provided on Pharma Isolator Validation

Pharma Isolator what is an Isolator
Pharma Isolator what is an Isolator how to do Isolator Validation

Principle of working of Isolator?

Isolators are fabricated with stainless steel 316 grade and the inner surface is polished so that easy cleaning and disinfection can be done. Isolator is completely covered, there is a port to put material inside the isolator with a facility to lock on the port. The inner side port is opened from the inner side without exposure to the outer environment and material is transferred inside the isolator and the inner port is closed again.

To handle material inside the isolator glove ports are provided, on these glove ports sterilized gloves are affixed through which one can put their hands inside the glows and handle the material inside the isolator.

These ports can also be used to put media plates inside the isolator during environmental monitoring inside the isolator for viable count, readymade stick plates are available with a box which can be attached readily with these ports. Isolators are provided with Integrated particle monitoring connections and connection for viable and non-viable particle monitoring equipment.

There are two types of isolation techniques based on the pressure inside the isolator, positive pressure isolation and negative pressure isolation.

According to air flow patterns there are two types of isolators: the laminar air flow isolator and turbulent air flow isolator. Automated pressure hold test on-board air compressor.

Validation of isolator and online General Processing Platform Isolators.

During validation requirements of 21 CFR Part 11 are required to consider which are as follows

1.Asses to operation with password to operators, restriction of data access to supervisors with password protection. Restriction for data modification access to manager with password protection.

Data backup and storage, restrictions on modification of data are required, audit trails and automated logs of the activity are required to be captured and stored in data, and whenever required a print in format can be generated.

Following tests are done for validation of an isolator.

  1. Air velocity test of the air coming from the HEPA or ULFA filters in the air supply.
  2. Filter leak test for HEPA filters and ULFA filters.
  3. Pressure differential measuring. Pressure differential between the surrounding area and the inside of the isolator.
  4. Glove integrity test.
  5. Particle count inside the isolator, as per the requirements for sterile dosage form manufactured in the isolator requires the isolator qualify for class A.
  6. Viable Particle count inside the isolator with settle plate method and viable count on the wall and mountings inside the isolator with stick plate method.
  7. Operability test of isolator system at variable speed at lower speed, at moderate speed, at high speed, after this test a optimum speed to be defined for the equipment.

8.Design qualification, Installation qualification, and operation qualification as done for equipment qualifications and validation to be performed.

USFD Approved New Drug Leqembi containing lecanemab-irmb for early stage of Alzheimer’s Disease

New drug Leqembi containing lecanemab-irmb for treatment of Alzheimer’s disease approved by US FDA under accelerated approval pathway.

There are very few treatments available for treatment of Alzheimer’s disease, people affected with Alzheimer’s disease are not able to do daily tasks, and there is a risk of forgetting the way back to home when they go out of home.

Pathophysiology of Alzheimer’s Disease

Alzheimer’s disease occurs due to loss of neurons in the brain and their connections to other neurons, as a result of increased amyloid beta plaques and neurofibrillary, or tau, tangles. Person affected with Alzheimer’s disease loses capability of thinking and memorizing things, and the patient loses memory. Disease is devastating to patients as well as family members of patients as one has to take care of the patient all the time.

The US FDA has approved Drug Leqembi containing lecanemab-irmb monoclonal antibodies against Amyloid beta, for treatment of early stages of Alzheimer’s disease. Drug Leqembi is not approved for late stages of disease. Leqembi is manufactured by Eisai R&D Management Co, it contains lecanemab-irmb is a monoclonal antibody consisting of immunoglobulin (IG g) which neutralizes gathered soluble and insoluble forms of amyloid beta plaques.

Alzheimer's Disease New Drug Leqembi lecanemab-irmb Reduced Amyloid beta plaque Alzheimer's Disease New Treatment Medicine
Alzheimer’s Disease New Drug Leqembi lecanemab-irmb Reduced Amyloid beta plaque Alzheimer’s Disease New Treatment Medicine


In a clinical trial safety and efficacy of Drug Leqembi was evaluated by giving patients affected with mild dementia with amyloid beta dosage of drug Leqembi (lecanemab-irmb) was given 10 mg / KG of body weight. every 14 days. It was observed that these patients who were receiving drug Leqembi (lecanemab-irmb) were found to be with reduction in brain amyloid beta plaque.

The drug Leqembi (lecanemab-irmb) acts on the basic root cause of Alzheimer’s disease, the brain amyloid plaque, therefore US FDA have approved this drug under accelerated approval pathway.

Side effects of the drug are headache, amyloid-related imaging abnormalities (ARIA), temporary swelling over the brain with mild bleeding, swelling ceases up on treatment, reactions associated with sterile dosage form and monoclonal antibody infusions. Drug Leqembi (lecanemab-irmb) is not approved for late stage Alzheimer’s disease.

Also see Sildenafil in treatment of dementia.

What is  Alzheimer’s Disease 

US FDA approves New Drug for Anemia due to chronic kidney disease

Anemia due to chronic Kidney disease

US FDA approves new drug Jesduvroq tablets which contain daprodustat for treatment of Anemia in Kidney disease patients on dialysis.

First Orally taken drug approved for treatment of Anemia due to chronic kidney disease who is on dialysis for the past 4 months.
There are medicines available for treatment of anemia caused by kidney disease but all of these are given through injection, the injectable dosage form. US FDA on 1 Feb 2023 have approved a new drug for anemia associated with kidney disease and for those who are on dialysis for the last 4 months.

The US FDA has approved the drug Jesduvroq tablets which contain daprodustat. It increases the level of erythropoietin by inhibition of enzyme hypoxia-inducible factor prolyl hydroxylase. Hypoxia-inducible factor binds with HIF-1 Beta and triggers transcription of genes which are responsible for erythropoiesis, glycolysis, and angiogenesis.


This drug is not approved for patients which are not undergoing dialysis, since the further clinical trials are to be conducted on the population which are not undergoing dialysis.

Because it is likely that the drug may affect renin angiotensin aldosterone system as well and increase blood pressure due to increased sodium and chloride reabsorption, and vasoconstriction, the effect of increased renin angiotensin hormone which are secreted from kidney.
Side effects of daprodustat are increased blood pressure, allergic reactions, pain in abdomen, thrombotic vascular events, giddiness.

Drug has boxed warnings about thrombotic vascular events, heart failure formation of blood clots in lungs and legs, hospitalization for heart failure. Also see: Erythropoesis Stimulating drugs and risk of cardiovascular disease

Relation between kidney and anemia:
Anemia is caused by deficiency of red blood cells, when red blood cell count drops down, it causes dropping of hemoglobin in the blood. Hemoglobin is responsible for carrying out transportation of oxygen from lungs to all parts of our body.

Anemia due to chronic Kidney disease
Chronic Kidney disease

Patients suffering with anemia suffer from lack of oxygen level in their body and weakness of muscle and body. Kidney plays an important role in production of red blood cells, kidney secretes a hormone called erythropoietin, erythropoietin signals generation of red blood cells.

In case of kidney disease erythropoietin secretion is deficient which leads to reduction in red blood cells. Kidney also secrete renin and angiotensin hormones which regulate reabsorption of sodium and chloride and potassium, it increases reabsorption of sodium and chloride ions and decreases potassium reabsorption from glomerular tubules sites.

Drugs Causing Birth Defects

Drug that causes birth defects.

Birth defects are caused when pregnant women take medicines listed below and various other unknown reasons.

There are some medicines which are necessary for some women. They must take medicine for maintaining health. For example medicines for asthma and epilepsy cannot be stopped. But the very same medicines can cause birth defects in children if they are consumed during pregnancy. Medication is done by adapting a approach of risk and benefit if the benefits are more than risk physicians decide on continuation of the medicine.

Many people do not know about these medicines when taken during pregnancy can cause birth defects. Which are these medicines the general public must know about the drugs which when taken can cause birth defects in newborn.

Most common birth defects are defects of the neural tube,  Cleft Lip / Cleft Palate. Congenital heart defects. Improper development of Brain and Autism spectrum disorder.

Following are the medicines which may cause birth defects if taken for a longer duration during pregnancy, therefore every medicine should be taken after consultation with a family physician.

The Thalidomide drug was a tragedy in history where the newborn babies were born without limbs. Here is the detailed information about Thalidomide.

1) Valproates: valproate and tricyclic antidepressant, benzodiazepines.

2) Isotretinoin

3) Steroid containing drugs.

4) Prednisolone

5) Diethylstilbestrol

6) Male hormones

7) Thalidomide

8) Lithium Carbonate

9) Antibiotics like bleomycin, vincristine.

10) Anti cancer drugs containing nitrogen mustard ring. (Cyclophosphamide)

11) Some medicines used for HIV infection.

12) Cocain, Benzocaine

13) Medicines which are used for treatment of tuberculosis. Except Vitamin B6

14) Warfarin

15) Thyroid medicines

16) Nonsteroidal anti-inflammatory medicines prolonged use and in high dosage.

Following chemical fumes are toxic and may cause birth defects in event a pregnant woman is exposed to them.

17) Formaldehyde fumes

18) Ethylene oxide traces

19) Pyrethrin and allethrin containing topical lotions, sprays

Source :

Camera system for Blister Packing

Camera system for Blister packing Machine. How camera system works on blister packing ?

Camera system in tablet blister packing machine is a system capable of identifying black spotted tablets, broken tablet, and unfilled pockets, or any other defective tablet, when the defective tablet or capsule goes in pocket of the blister, camera identifies these defective tablet and the same strip is the rejected removed from the blister belt by rejection mechanism.

These rejected strips can be taken and defoiled/ deblistered, and good tablets if any can be removed and rejected tablets can be destroyed.

The camera system is initially feed with the data photographs of the defective tablets or capsules and open blisters with all possible defects, black spotted tablets placed at all the blister points in the blister and these photographs are stored as data for comparison. This is called calibration of the defective samples. Along with this data of good blisters is also provided in the form of photographs. With the help of sensors and the comparison of pics camera system removes out defective tablets capsules and rejection arm ensures that these defective tablets are removed from packing line.

There are many types of sensors which are used in pharmaceutical industry which are used to remove the defective pack away from packing line with the help of rejection arm.

Different types of sensors are: 1) Photo electric sensors. 2) IR sensor 3) Lesser sensors 4) Induction. These sensors are checked for their working condition and on daily basis a challenge test is performed on the blister packing machine and verified if the deliberately added broken tablet strip blister pack is rejected from the line.

The qualification or validation of the Camera system is an exhaustive activity, which requires to challenge the camera system for blister by adding different defective samples in the feeder and verify that the defective tablet or defective capsule containing blister is rejected and removed from the line.

Following defective product is added to challenge the camera system during qualification or validation.

Broken Tablets, Different Colored tablet, different shape tablet, Black spotted tablet, Half-filled or empty pocket tablet blister.

ACG Inspections Online inspection camera systems inspection systems

Camera  system for Blister Inspection system
                  ACG Blister Inspection System

Clean Room Validation Recovery test

How a recovery test is done during validation of AHU/clean room in pharmaceutical manufacturing?

Recovery test in AHU or clean room validation is a test where the ability of the clean room or AHU to maintain the level of cleanliness or the particle count below the rated classification limit.

In the process clean room is sprayed with known number of particles. Aerosol of particles of known concentration and known size is sprayed in the clean room, and the time taken by clean room to filter out and clean the sprayed particles to the average count of the clean room is checked.

This is a kind of challenge test, like we do challenge test for empty blister rejection on tablet packing machine or on checkeweigher.

A known amount of particle aerosol is sprayed in the clean room and time taken to clear the particles to the base line particle count is noted.

This data is used to assign the cleanup time of the clean room, which helps pharmaceutical manufacturing pharmacist for planning for the actual work in the clean room.

How much concentation of particles should be taken for recovery test?

Guidelines suggest that the particles sprayed in the recovery test should not be unnecessarily high. There is no point in keeping higher concentration. Since the aerosol it self may lead to untoward effect on the cleaness. Therefore even the ISO standards mention this. Particle count taken for recovery test should be aroun 100th of desired cleaness level.
But this some times is not recommended.
Arosol concentation should be taken 1.5 of the baseline particle count obtained in notmal working of Clean Room. For an example the clean room is grade A and particle count for grade A qualification is 3500 particles of not mor than 0.5 microns.
And the observed mean count on day today basis is 2000 particles. This is the baseline count of the clean room. And 1.5x 2000 number of particles should be sprayed in the room to study the recovery. Then 3000 number of particles will be loaded in the clean room during the validation process, or recovery test, this will not create risk associated with higher number particle recovery test

Clean Room Validation in Pharmaceutical Industry how to do

Clean Room Validation how it’s done different requirements of clean Room Validation from particle Count to Microbial Count Limits methods to do it?

Validation is an important activity in Pharmaceutical Industry, it impart trust on the process and inturn the product manufactured.

For doing validation of clean room, unless all the installed equipment are validated, the Clean Room validation activity In an clean room don’t get complete.

Validation activity of a Clean Room requires to do are as follows.

1.Proper fitment of filters, check if there is any leakage of air from the joint of filters.

2. Filter integrity test, to verify if there is any damage inside the HEPA filter.

3. Air velocity test.

4. Airflow patern test. Air flow visualisation.

5. Particle count at Rest and at working condition

6. Viable microbial count in clean room at working as well as rest condition.

Before proceeding for above tests for validation of clean room the of the equipments installed in the clean Room are required to be validated.

For example a clean room in a sterile pharmaceuticals manufacturing, requires Isolators and other barrier technology equipments RABS. These equipment have different set of requirements, like laminar air flow and air pressure, gloves integrity ect. These equipment must be validated by the set of test recommend for them.

Fliter Fitment: There should not be any leakage of air from sealing points, so that unfiltered air is blown inside the clean room without filtering.

Filter integrity test: PAO aerosol test, the aerosol of fine particles of poly alpha olyphine is put inside the filter and verified is the filter media capable of filtering out abou 99.997% of the aerosol particles.

Air flow pattern study: This is important since it gives idea if the all air is filtered or not and is the air flow capable of preventing cross contamination. It give idea about air flows is the air flow in the direction as planned from the area designed to be higher pressure to area designed as low pressure, and the air is again taken back from return air points in clean room.

FDA guidelines Europian Unions Guidelines mention that videography of the Air flow pattern should be done by making use of smoke, making use of dry ice smoke or sutable smoke generator.

Air Velocity: Air velocity is measured at different points from the supply air filter, at different positions, anemometer is kept at corners and at central position on the filter.

Why Air velocity is measured:

By measuring air velocity, we come to know how fast the air in the clean Room is filtered and made particle free. More is the air velocity, more will be the CFM, more will be the Air Changes per hour and air inside the room will be more cleaner.

What is CFM : CFM is the measure of amount of air propelled in to the clean room per minute the amout of air is measured as cubic feet, therefore CFM means cubic feet per minute. CFM depend on the speed of the blower in the Air handling unit. 










Clean Room Validation Microbial Count Limits

Microbial action limits for clean room

Clean Room Validation Microbial Count Limits method settle plate contact plate viable bacterial fungal count limits frequency of validation.

Classification of clean rooms in pharmaceutical manufacturing companies is part of validation activity, a clean room is designed to provide the desired level of clean grade environment. but it’s rated only to a particular grade after it is validated that the clean room is providing the desired level of particle count. As per the ISO 14644-2 and ISO 14644-3 specifications for validation of clean room.

European Union Guidelines for Pharmaceutical Clean Rooms have provided the limits for viable bacterial and fungal count. Which is provided below.

The European Union Guidelines also require that the limits are met at working as well as at rest conditions for the clean room.

Process of validation of a clean room should be planned in advance, an activity similar to the product manufacturing can be mimicked and particle count should be done at the points as per the guidelines provided in ISO 14644-2 and 3 specification.

Microbial Limits and Methods for Settle Plate and Contact Plates evaluation of Clean Room Viable Microbial Count for Validation of Clean Room.

Microbial action limits for clean room
Microbial action limits for clean room

Microbial count is done by the settle plate method, plates are exposed for the duration of the process of manufacturing or not more than 4 hours, media plates should not get dried during exposure.

After cleaning the surfaces of the clean room and floor with detergent and water, followed by disinfectants.

Contact plate is used to take viable microbial counts from the surfaces of a clean room and growing and hand gloves of personnel working in the classroom. Both bacterial and fungal count is required to be taken, for bacterial and fungal count microbial nutrient media plates for contact plate method have different Colour for identification pink Colour is given for Fungal count plate.

Previously sterilized with Gamma radiation, prefilled with media, contact plates are provided with three outer bags of polythene. When these plates are taken into the Airlock of the Clean Room upper two bags are removed. Which ensures that outer contamination is removed. The inner bag is sterile and is removed just before the contact plate sample is taken from the surface. Place is placed over the surface with equal pressure and removed and the lid is covered.

Some contact plates come with locks on bottom and cap plate, when it is closed it provides anaerobic conditions inside the plate.

During qualification of clean room at working condition the microbial count from the personal gowning and hand is taken, for class A it should be zero. Any increase in microbial count should be investigated and root cause should be identified.

Clean Room Validation Microbial Count Action Limits for Surfaces.

Action limits for viable microbial count from Gloves and Gowns
Action limits for viable microbial count from Gloves and Gowns.

Clean Room Revalidation Frequency.

For Class A and B  Clean Room Validation Frequency provided in guidelines is Six months while for Grade C and Grade D Clean Room it is 12 months.

Metal detector to remove metal particle tablets during manufacturing

Metal detector system to eliminate metal particle containing tablets during manufacturing.

Question: How to remove metal particles if any which might be getting generated during manufacturing due to wear and tear of machines.
Answer: Source for Metal particles in a tablet dosage form may be one of following.
Raw material, Defective equipment, like broken sieve mesh, compression machine wear and tear.
Following care can be taken to eliminate the risk of metal particles getting entrapped in the tablet.
Addition of a test of magnet on raw material sample during testing and sampling, a magnet can be hovered over the sample or inside the raw material container during sampling, if there are any metal particles they will get attracted over magnet and can be detected, such raw material will get failed during sampling itself, same can be done during testing of sampled raw material. Visual inspection of sampled raw material for nonmagnetic metal particles is and black particle other contaminant is required to do.
Some sieves come with magnetic ring at periphery of the sieve by virtue of which the ferromagnetic metal particles can be removed during sieving or shifting of the raw material before addition in to the blender.

Metal Detector
         Metal Detector for tablets

What to do even after this metal particle goes in to tablet unnoticed.
There are metal detectors available in pharmaceutical machinery manufacturers, these metal detectors are capable of identifying nonferrous or stainless steel particle of 0.5 mm and ferrous metal particle of size 0.3 mm. This metal detector equipment’s when placed below the compression machine chute, collecting the tablets, tablets when run through the metal detector a tablet with nonmagnetic or nonferrous metal particle are detected and removed away in the rejection bin, these can be destroyed later on. The speed of the metal detector depends up on the size of tablet, for smaller tablets it can process about 5000 to 6000 tablets in a minute for tablet of weight up to 350 mg 10000 tablets for tablets below 250mg, while for bigger tablets it will be 3000 to 5000 tablets, one can add additional metal detector for higher output. Manufacturer can enhance the capacity.
Why alarm system is put on the metal detectors systems.
Alarm system get activated when a tablet with metal is detected and removed away from the good tablets, the alarm is for alert for the supervisors and pharmacists working for taking further precautions if required.
Validation Verification Challenge test of metal detector system:
Before starting of the operation on daily basis a test is designed to challenge the metal detector by sending a tablet with metal particles of ferrous 0.3 mm size, nonferrous 0.5 mm size.
System can be validated by adding known number of samples of tablets in the tablets being inspected and crosschecking if the metal detector can remove the added tablets, if the metal detector removes all tablets with metal particle successfully is verified, up on successful run on three consecutive batches the equipment can be said to be validated to remove metal particles in the tablets.

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