Pellets
Pellets are free-flowing, small, and spherical, or round-shaped particles prepared by the agglomeration of granules or fine powders that contain drug substances and excipients using suitable processing equipment.Pellets are small in size, ranging from 0.5 to 1.5 mm.
In other words, pellets are free-flowing spherical or round units that are obtained by agglomeration of fine powders or granules of the bulk drugs and excipients by pelletization techniques. The pellets have low porosity, which is around 10%.
Pellets are either filled into hard gelatin capsules or compressed into disintegrating tablets.
Read more - Hard Gelatin Capsules | Manufacturing Methods
The shapes and sizes of pellets permit their administration as an oral drug delivery system as well as for injections.
When pellets are prepared for oral administration, they quickly release their contents into the stomach and get distributed throughout the gastrointestinal tract, and also produce maximum absorption of the drug and minimize irritation.
The shapes and sizes of pellets permit their administration as an oral drug delivery system as well as for injections.
Application of Pellets in Pharmacy
1) Pellets improve the aesthetic appearance of the products.2) Pellets also offer dosage uniformity.
3) Pellets also minimize inter as well as intra-patient variability.
4) The lower risk of dose dumping is provided by pellets.
5) In the formulation development, the pellets show excellent flow properties.
6) By coating the drug pellets with different polymers, they are used to achieve a controlled release rate of drugs.
7) If the drugs are chemically incompatible with each other, then they can be formulated into pellets and delivered in a single dosage form by encapsulating them.
Read more - Solid oral dosage Forms (Tablets or Capsules)
8) There is no kind of dust formation that occurs while formulating the pellets, although fine powder causes dust explosions and also causes health problems.
9) For achieving content and uniformity of weight, the high bulk density of pellets plays an important role in achieving it.
10) Pellets minimize the peak plasma fluctuations and also reduce the potential side effects with improved drug bioavailability.
2) Pellets provide uniformity of dosage.
3) Prevention of dust formation as compared to fine powders.
4) The application of pellets shows controlled release, due to which the ideal low surface area-to-volume ratio occurs.
5) For the immediate release drugs large surface area of the pellets provides better absorption, distribution, as well as dissolution.
6) Pellets provide improved flow properties as well as flexibility in the formulation, development, and manufacturing of dosage forms.
7) The pellets can provide different release rate profiles either at the same or different sites in the gastrointestinal tract.
2) As pellets are too rigid, it is very difficult to compress pellets into tablets. Hence, pellets are delivered encapsulated in hard gelatin capsule shells.
Read more - What is the tablet dosage form?
3) The manufacturing process of pellets is too complicated, and many process variables are involved.
4) The pelletization process requires highly specialized equipment, and the cost of manufacturing increases.
5) A Large amount of coating is given to the pellets, so a high specific surface area per dose is required.
Read more - What is the film coating of tablets?
8) There is no kind of dust formation that occurs while formulating the pellets, although fine powder causes dust explosions and also causes health problems.
9) For achieving content and uniformity of weight, the high bulk density of pellets plays an important role in achieving it.
10) Pellets minimize the peak plasma fluctuations and also reduce the potential side effects with improved drug bioavailability.
Advantages of Pellets in Pharmacy
1) The sphere or round shapes of pellets have an excellent flow property.2) Pellets provide uniformity of dosage.
3) Prevention of dust formation as compared to fine powders.
4) The application of pellets shows controlled release, due to which the ideal low surface area-to-volume ratio occurs.
5) For the immediate release drugs large surface area of the pellets provides better absorption, distribution, as well as dissolution.
6) Pellets provide improved flow properties as well as flexibility in the formulation, development, and manufacturing of dosage forms.
7) The pellets can provide different release rate profiles either at the same or different sites in the gastrointestinal tract.
Disadvantages of Pellets in Pharmacy
1) Formulation of pellets is time taking process and very complicated.2) As pellets are too rigid, it is very difficult to compress pellets into tablets. Hence, pellets are delivered encapsulated in hard gelatin capsule shells.
Read more - What is the tablet dosage form?
3) The manufacturing process of pellets is too complicated, and many process variables are involved.
4) The pelletization process requires highly specialized equipment, and the cost of manufacturing increases.
5) A Large amount of coating is given to the pellets, so a high specific surface area per dose is required.
Read more - What is the film coating of tablets?
Formulation Requirement of Pellets or Pellets Formulation
Active Pharmaceutical Ingredient (API)
It is a multiple-dose form technology that has the potential for the delivery of a variety of active pharmaceutical ingredients.Different types of drugs can be used to develop sustained release, immediate release a well as taste masking pellets with various applications in different aspects.
Pellet technology is widely used to deliver gastrointestinal tract (GIT) at a specific site to release medicaments in a controlled manner.
Immediate release
Delivering drugs in the form of pellets shows an increased surface area as compared to compressed tablets and capsules.This significantly reduced the time that is required for disintegration, and pellets also have the capability for use as rapidly dispersible tablets.
Sustained release
In the manufacturing of the sustained-release dosage form of drugs, pellets are being progressively used.Read more - dosage forms.
Taste masking
When a decrease in taste is required, micro pellets are ideal for such products.Without lowering the bioavailability of the oral dosage forms, pellets provide masking of the unpleasant taste of such drugs.
Binder
Binder is also called a bridging agent or agglomerating agent.Binders are adhesive materials that can be added to pellet formulations to bind the powders.
The addition of binder in the solution form, as compared to the dry form, may be more efficient than dry mixing followed by liquid addition.
Examples - Gelatin, Starch, Sucrose, Polyvinylpyrrolidone (PVP), and Hydroxypropyl methylcellulose (HPMC).
Granulating Fluid
The moisture content of the wet mass is a very essential parameter for the pellets as it relates to the plasticity requirements, as well as the cohesiveness of the wet mass to extrude and spheronize it to provide a perfect spherical shape.Examples - Ethyl ether, dilute acetic acid, isopropyl alcohol, and alcoholic or hydroalcoholic systems.
Spheronizing Enhancer
These are the formulation aids that improve the production of spherical pellets, generally during the spheronization process.Spheronizing Enhancers not only improve the plasticity of the formulation but also improve the binding properties that are essential for pellet strength.
Example - Microcrystalline cellulose
In the pelletization process, 70 to 80% of the excipients are formed by the fillers.
Example - Microcrystalline cellulose, Glyceryl monostearate, Starch RX1500, spray dried lactose, Avicel PH 101
Example - Propylene glycol, Glycerol, and derivatives of phthalate like dimethyl, diethyl, and dibutyl phthalate
Although during Extrusion-Spheronization and compression, lubricants do not play an important role in the formulation of pellets.
Lubricants reduce the friction between the die wall and material either during the compression or at the ejection phase.
Example - Glycerin, Magnesium stearate, Calcium stearate, and Polyethylene glycol.
These agents are incorporated in the formulation to prevent pellets from attracting one another due to surface charge during the process.
Example - Talc, Silicon dioxide, Kaolin
Generally, surfactants are added to the liquid to enhance the wettability by minimizing the interfacial tension between the liquid and drug particles.
Example - Hydrophobic substances, Inorganic salts, hydrophilic polymers
Mainly, acid-labile drugs are protected from the pH conditions of the gastrointestinal tract by applying the enteric coating.
To maintain the stability of the core in a desirable range, buffer systems may also be added to the core formulation.
Example - Citrate, Phosphate.
To improve the possibility, either natural sweeteners or synthetic sweeteners are used.
Example - Sucrose, Dextrose, Maltose, Glucose, and Fructose.
Example - FD&C-approved coloring agents
I hope that you have liked the article on Pellets or Pellets in Pharmacy. If you have any queries, please ask in the comments. I will be happy to help.
Filler
Fillers are the excipients that are used to provide the bulk to the material.In the pelletization process, 70 to 80% of the excipients are formed by the fillers.
Example - Microcrystalline cellulose, Glyceryl monostearate, Starch RX1500, spray dried lactose, Avicel PH 101
Plasticizer
Plasticizers improve the flexibility of polymers by reducing their tensile strength.Example - Propylene glycol, Glycerol, and derivatives of phthalate like dimethyl, diethyl, and dibutyl phthalate
Lubricant
As high-speed rotary equipment is being used in the preparation of pellets, in the pelletization process, lubricants are rarely used.Although during Extrusion-Spheronization and compression, lubricants do not play an important role in the formulation of pellets.
Lubricants reduce the friction between the die wall and material either during the compression or at the ejection phase.
Example - Glycerin, Magnesium stearate, Calcium stearate, and Polyethylene glycol.
Separating Agents
Separating agents are substances that adsorb on the surface and enhance the pellet's separation into the individual units during the process of pelletization.These agents are incorporated in the formulation to prevent pellets from attracting one another due to surface charge during the process.
Example - Talc, Silicon dioxide, Kaolin
Surfactant
In the pelletization process, initially, at the time of pellet formation, the growth of smooth-surfaced spherical pellets depends on the liquid bridges that are mainly on water.Generally, surfactants are added to the liquid to enhance the wettability by minimizing the interfacial tension between the liquid and drug particles.
Release Modifiers
To formulate the pellet cores that have specific release profiles in a single step, which may be achieved by the addition of release modifiers along with the drug during the core formulation.Example - Hydrophobic substances, Inorganic salts, hydrophilic polymers
pH adjusters
These are the substances that are added into the pellet formulation, which enhance the microenvironment of drug molecules used for various reasons.Mainly, acid-labile drugs are protected from the pH conditions of the gastrointestinal tract by applying the enteric coating.
To maintain the stability of the core in a desirable range, buffer systems may also be added to the core formulation.
Example - Citrate, Phosphate.
Flavoring agent
The flavor choice is depending from person to person, which may be changed as per age as well as taste. It plays a significant role.Sweetening agent
In the case of pediatrics, the sweet taste in the formulation is much preferred.To improve the possibility, either natural sweeteners or synthetic sweeteners are used.
Example - Sucrose, Dextrose, Maltose, Glucose, and Fructose.
Coloring agents
To improve the appearance and make it more patient-compliant, coloring agents are generally used.Example - FD&C-approved coloring agents
I hope that you have liked the article on Pellets or Pellets in Pharmacy. If you have any queries, please ask in the comments. I will be happy to help.
Read more - Pre-compression evaluation of tablets
Read more - Soft gelatin capsule manufacturing
