Introduction to Pharma Tablet Coating
Pharmaceutical tablet coating is a critical process in the manufacturing of drugs. It includes coating tablets with a thin layer of material in order to protect them from external environments including moisture, light, and air while also enhancing their look, flavor, and texture. The coating is also helpful in controlling the release of the tablet’s active chemicals, ensuring that they are released at specific locations.
Pharma tablet coating can be made by different methods such as spray coating, dip coating, and pan coating. Each procedure has advantages and disadvantages, and it depends on the types, shapes, and sizes of the tablets.
In this article, we will examine the role of pharma tablet coating, issues related to pharmaceutical tablet manufacturers, Coating Area Interview Questions/ Answers with their solutions including common queries and guidelines for proper tablet coating.
Importance of Coating in Pharmaceutical Manufacturing
Pharmaceutical production is a complex procedure that requires precision and close attention to every detail. Tablet coating, which includes spreading a thin layer of coating material onto a tablet’s surface. The coating protects the tablet from moisture, enhances its look, and covers up unpleasant flavors or odors, among other important features.
Besides these practical advantages, tablet coating may also improve the therapeutic effect of some drugs. For instance, an enteric coating prevents medicines from releasing into the stomach. Whereas in the sustained release coating, the medication is a coating that facilitates the release of the drug very slowly for a prolonged period, attaining the desired long-lasting effect.
Tablet coating forms and remains an important aspect in the production of pharmaceuticals. Therefore, it is important to take the necessary measures to make sure that the tablet coating procedure is done right. If not, tablets produced will be ineffective, unstable, or even dangerous. So there is really no diapering the fact that right tablet coating technique is a prerequisite to the production of Quality products by a pharmaceutical manufacturer.
Common Challenges in Pharma Tablet Coating
- Drug tablet coating is an essential stage in the drug manufacturing cycle. Uniformity of coating thickness is one of the problems manufacturers face when coating tablets. This is because it is difficult to achieve uniform coating on all tablets since not all of them are of similar size and shape, there are always some variations.
- Sticking to the tablets is another challenge. The coating of the drilled holes is very delicate since the tablets are prone to sticking to each other, hence leading to poor coatings of a tablets. This can be as a result of spray rate, position of the nozzle, or Temperature within the coating pan.
- Furthermore, tablet cracking and chipping take place during the procedure. When the tablets are too much their brittleness or the coating solution is in excess its viscosity, this may occur. This is due as well to over-drying the tablets, which may shrink and crack the core of the tablet.
- During the coating process, operation area cleaning deficiency or personnel contamination from other activity areas producing other products may lead to contamination of the coatings as well.
- These problems may lead to extended process wastes, higher expenses, or even product retrieval. so it becomes important for the manufacturer to reduce these problems.
Coating Area Interview Questions/ Answers for Officer
Asking the right questions during an interview is crucial to finding the best candidate for a pharma tablet coating supervisor position. Here are some questions that can help you identify the most qualified candidates:
Asking the right questions during an interview is crucial to finding the best candidate for a pharma tablet coating supervisor position. Here are some questions that can help you identify the most qualified candidates:
- What experience do you have within the field of pharma tablet coating?
- Can you list some of the examples of the coatings used in the production of pharmaceutical products?
- What procedures do you follow to ensure that the coating is uniformly distributed and is the same for all the tablets?
- Have you ever met any problems during the coating process? How did you deal with them?
- What measures do you put in place to ensure quality during the coating procedures?
- Can you describe what happens if standard operating procedures (SOP) are not adhered to during the course of pharma tablet coating?
- How do you learn or access information with an emphasis on new technology especially in regard to pharma tablet coating?
- Could you name the most successful project on pharma tablet coating that was realized by you at your working place?
- How do you manage your time effectively in case of working on numerous projects concurrently?
- How do you integrate yourself into the coating process with other team members like engineers and quality control people?
Answers to Frequently Asked Questions about Pharma Tablet Coating
Pharmaceutical tablet coating is one of the final steps that is carried out in the process of tablet formulation in which pharmaceutical polymer coating is carried out on the surface of the tablets. Like any other manufacturing process, there are bound to be a number of questions and concerns about pharma tablet coating. Here are Some Coating Area Interview Questions/ Answers:
Q: Why are tablets coated in pharmaceutical industry?
Ans: Coated tablets are rather prepared for use than in their uncoated form, and thus their coating also protects the tablet from the adverse effects of the outside environment. Fruits and vegetables have been bothered by these very aggressive factors, which include moisture, light, air, and perfumes. Coated tablets also have benefits of masking the taste and odor of the drug and more improve patient adherence as they make it easier to take.
Q: What are the coating materials routinely employed in pharmaceutical tablet coating?
Ans: The most common coating materials in pharma tablet coating are polymers like cellulose derivatives, acrylics, and polyvinyl alcohols.
Q: How do you determine the coating thickness?
Ans: The coating thickness is contingent upon the coated drug and required release pattern. In general, the coatings constitute 2-10% of the weight of the tablet.
Q: What are the different kinds of coating processes available?
Ans: There are several types of coating processes, including film coating, sugar coating, and enteric coating. The film coating is considered the most preferred method currently in vogue in the modern manufacture of pharmaceuticals.
Q: What should I do if I want to carry out orientation on every completed coating of pharmaceutical tablets?
Ans: To guarantee successful pharma tablet coating, it is critical to select an appropriate coating material, define the specific parameters for the coating process, and conduct quality control of manufactured articles. It is also beneficial to seek assistance from professionals in pharma tablet coating.
Q: What is Conventional Coating Pan:
Ans: The conventional coating pan is a system used in tablet coating that can be described in two ways:
The immersion sword system includes a device in the form of a metal sword that penetrates into the bed of the tablets. During the drying process, it introduces drying air, which flows through the perforated metal sword and then upwards towards the bed.
An immersion tube system is a type of apparatus in which a type of tube is submerged within a bed of tablets, with one of the tubes having a spray nozzle through which hot air and a coating solution are provided. This system can also be utilized for sugar coating and film coating.
Q: What is perforated coating Pan:
Ans: A perforated coating pan is another type of system used in tablet coating. Here’s how it works:
The coating drum comprises a cylindrical enclosure containing various configurations of external spray impellers. These spray nozzles atomize the coating solution. In this coater, dry inlet air flows from the upper section of the drum, passing in between the tablets, and exits the drum through the perforations.
Slew of equipment such as Accela-coat system, Hi-Coater system, Dria coater, Glatt coater, and so on come under this category of systems for coating.
Q: What are the methods used in tablet coating:
Ans: Generally, three methods are used for tablet coating:
A) Sugar coating.
B) Film coating.
C) Enteric coating.
Q: Which polymers are used in enteric coating:
Ans: Polymers used in enteric coating include Cellulose acetate phthalate, Acrylate polymers, Hydroxypropyl methylcellulose Phthalate, Polyvinyl acetate phthalate, and Shellac.
Q: Which solvents are used in film Coating:
Ans: IPA (Isopropyl alcohol) and Methylene chloride are mainly used as solvents in film coating.
Q: Which materials are used as opacifiers in film Coating:
Ans: The opacifying substances within the film coating contain titanium dioxide, talc, and aluminum silicate.
Q: Which colorants are used in film coating:
Ans: FD and C colors, D and C colors, iron oxides, Carmel, and turmeric are mainly used as colorants in film coating.
Q: What are the Process parameters to be checked during Coating:
Ans: There are a number of variations that need to be taken care of during the coating, namely, inlet temperature, outlet temperature, spray rate, atomizing air pressure, pan RPM, gun height relative to the tablet bed, weight gain composition of the tablets, flow rates of peristaltic pumps, monohydrate hardness of tablets, target weight of the tablet units and their external characteristics.
Q: What are the defects of Coated tablets:
Ans: Common defects observed in coated tablets include twins, cracking, partially coated tablets, incomplete drying, edge broken, peeling, print defects, shade variation, weight variation, and debossing/embossing. fill.
Q: What are the reasons for Edge Chipping of tablets in Coating:
Ans: The possible causes of edge chipping of tablets during the coating process include:
- Low tablet hardness.
- Low tablet friability.
- Tablets have sharp edges.
- Low spray rate.
- Low mechanical strength of the tablets.
- The low solid content in the coating solution.
Q: What are the reasons for the Color variation of tablets in Coating:
Ans: The potential reasons for the color variation of tablets during the coating process are as follows:
- Inadequate mixing of tablets during coating.
- Poor spray pattern.
- Pan speed set too low.
- Applying too little coating solution.
- The high solid content in the coating solution.
- The insufficient number of spray guns.
Q. What is tablet coating?
Ans: Tablet coating is the process of applying a thin layer of coating material over the tablet surface, which is rotating in the coating pan.
Q. Why do we perform tablet coating?
We perform tablet coating to:
- Mask the unpleasant taste of the drug
- Protect the drug from temperature and humidity
- Modify the release of the drug (e.g., enteric coating)
- Prevent mix-ups by adding different colors to tablets of different strengths
Q. What are the types of tablet coating?
Ans: There are three main types of tablet coating:
- Film coating
- Enteric coating
- Sugar coating
Additionally, drug coating is also performed nowadays.
Q. What are the types of coating based on the solvent used?
Ans: There are three types of tablet coating based on the solvent used:
- Aqueous coating
- Organic coating
- Hydro-alcoholic coating
Q. What are the types of tablet coating based on the release pattern of the API?
Ans: There are two types of coating:
- Functional coating
- Non-functional coating
Q. What is functional coating?
Ans: There are other functional coatings that modify the release of the API, this is the case for multiple functional enteric coating e.g. Eudragits.
Q. What is non-functional coating?
Ans: Non-functional coating does not affect the release pattern of the API, such as film coating or immediate-release tablet coating.
Q. What is the principle of tablet coating?
Ans: The principle involves applying coating suspension over rotating tablets using spray guns. Heat is supplied to evaporate the solvent, and the coating material is deposited on the tablet surface.
Q. What are the general components of the coating suspension?
- Solvent
- Film former or polymer
- Plasticizer
- Anti-adherents
- Opacifiers
- Colorants
- (Anti-foaming agents can also be added.)
Q. Give an example of a film-coating polymer.
Ans: Example: Hydroxypropyl methylcellulose (HPMC).
Q. Give an example of a polymer used for enteric coating.
Ans: Examples: Cellulose acetate phthalate (CAP) and cellulose acetate trimellitate.
Q. What are the general steps of the tablet coating process?
Ans:
- Pan loading
- Dusting
- Preheating
- Spraying
- Cooling
- Removing tablets from the coating pan
Q. What equipment is used for tablet coating?
Ans: Perforated and conventional coating pans, spray guns, piping system, peristaltic pump, and a mixing tank for suspension preparation.
Q. What is tablet bed temperature?
Ans: The temperature of the surface of rotating tablets during coating is known as tablet bed temperature.
Q. How is tablet bed temperature measured?
Ans: It is measured by a temperature-sensing probe or by using IR temperature-sensing guns.
Q. What are the defects of tablet coating?
Ans: Some defects include sticking, picking, orange peel effect, bridging, chipping, blooming, color variation, and weight gain issues.
Q. What are the critical process parameters of tablet coating?
Ans:
- Inlet air temperature
- Outlet air temperature
- Tablet bed temperature
- RPM of the peristaltic pump
- Atomization air pressure
- Tablet-to-gun distance
- Gun-to-gun distance
Q. How is spray gun validation performed?
Ans: Details are given in the video linked in the description.
Q. What is the importance of gun-to-gun distance?
Ans: Proper gun-to-gun distance prevents overlapping spray patterns (over-wetting) and ensures uniformity of color and weight.
Q. Give an example of a film-coated tablet.
Ans: Examples: Ciprofloxacin, levofloxacin.
Q. Give an example of an enteric-coated tablet.
Ans: Example: Aspirin.
Q. What are the steps of sugar coating?
Ans:
- Sealing
- Subcoating
- Smoothing
- Coloring
- Polishing
Q. Give an example of an opacifier used in tablet coating.
Ans: Example: Titanium dioxide.
Q. Give an example of an anti-foaming agent used in tablet coating.
Ans: Example: Simethicone.
Q. What is an example of a plasticizer?
Ans: Examples: Macrogol, and triacetin.
