Article

Advances in pharmaceutical coatings

Authors:
  • Bharati Vidyapeeth's college of Pharmacy, Navi mumbai
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Abstract

Recent trends in pharmaceutical technologies are towards the development of coating methods which overcomes the various disadvantages associated with solvent based coatings. In these newer technologies coating materials are directly coated onto solid dosage forms without using any solvent and then cured by various methods to form a coat, hence these methods sometimes called as solventless coatings. Various solventless coatings are available such as photocurable coating, magnetically assisted impaction coating, compression coating, hot melt coating, powder coating, electrostatic dry coating, supercritical fluid coating, herein only magnetically assisted impaction coating and electrostatic dry coating are discussed. This review summarizes the fundamental principles and coating processes of various dry coating technologies.

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... vi) To include every other drug or components adjuvant in the coating to keep away from Chemical incompatibilities or to provide sequential drug release. vii) To enhance the pharmaceutical elegance by means of use of unique shades and contrasting printing (Basu et al., 2013;Pawar et al., 2010;Reddy et al., 2013). ...
... As a result of the charge difference, they are transported towards the target and deposited. Tribo-charging is another method that uses the frictional charge of powder that is delivered through a pipe made of a certain material, such as PTFE, metal, or other powder particles [213,216,217]. Because tribo-charging leaves less charge on particles than corona charging [218], corona charging is the preferred method for electrostatic powder coating [219]. ...
... As a result of the charge difference, they are transported towards the target and deposited. Tribo-charging is another method that uses the frictional charge of powder that is delivered through a pipe made of a certain material, such as PTFE, metal, or other powder particles [213,216,217]. Because tribo-charging leaves less charge on particles than corona charging [218], corona charging is the preferred method for electrostatic powder coating [219]. ...
Article
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Food sectors are facing issues as a result of food scarcity, which is exacerbated by rising populations and demand for food. Food is ordinarily wrapped and packaged using petroleum-based plastics such as polyethylene, polyvinyl chloride, and others. However, the excessive use of these polymers has environmental and health risks. As a result, much research is currently focused on the use of bio-based materials for food packaging. Biodegradable polymers that are compatible with food products are used to make edible packaging materials. These can be ingested with food and provide consumers with additional health benefits. Recent research has shifted its focus to multilayer coatings and films-based food packaging, which can provide a material with additional distinct features. The aim of this review article is to investigate the properties and applications of several bio-based polymers in food packaging. The several types of edible film and coating production technologies are also covered separately. Furthermore, the use of edible films and coatings in the food industry has been examined, and their advantages over traditional materials are also discussed.
... x) Printing process can be done easily with this coating process [6,7]. ...
Article
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... It is also common to employ blending polymers to get suitable and desired results, as using a single polymer may not give the desired drug release profile. Owing to its hydrophobic properties, EC reduces the penetration of water into the solid polymeric matrix, hence reducing drug release [4,23]. EC can be found in different forms, such as powders with various viscosity grades or aqueous dispersions. ...
Article
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Article
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... Particles accumulate on the substrate before the repulsion force of the deposited particles against the coming particles increase and exceed the electrostatic attraction. Finally once the said repulsion becomes equivalent to the said attraction, particles cannot adhere to the substrate any more, and the coating thickness does not increase any more [7,8,9,10] . Magnetically assisted impaction coating (MAIC) ...
Article
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Tablet coating is one of the oldest pharmaceutical processes still is existence. Coating is a process by which an essentially dry, outer layer of coating material is applied to the surface of a dosage form in order to confer specific benefits over uncoated variety. It involves application of a sugar or polymeric coat on the tablet. The advantages of tablet coating are taste masking, odor masking, physical and chemical protection, protects the drug in the stomach, and to control its release profile. Coating may be applied to a wide range of oral solid dosage form, such as particles, powders, granules, crystals, pellets and tablets. When coating composition is applied to a batch of tablets in a coating pan, the tablet surfaces become covered with a tacky polymeric film. There are several techniques for tablet coating such as sugar coating, film coating and enteric coating. The disadvantages of the older techniques of coating have been overcome with the recent advancement in coating technologies. In these technologies coating materials are directly applied on the surface of the tablet without the use of any solvent. ICH guidelines also prefer the avoidance of organic solvents in pharmaceutical dosage formulations considering products safety profile. This review discusses the basic concepts of tablet coating, the recent advancements made, the problem faced during the process, their solutions and coating evaluation.
... Infact the formulation and clinical performance of dosage form depend on the physicochemical property of the polymer used in the formulations [1] .They are used as taste-masking agent, stabilizer, and protective agent in oral drug delivery. Polymers can bind the particles of a solid dosage form and also change the flow properties of a liquid dosage form [2]. Coating with water insoluble polymers is an important technique for targeted or controlled release formulations and the tastemasking of drugs, during which the aqueous polymer dispersions are widely used as an alternative to an organic polymer coating system [3] .Water soluble polymers are always being in good demand because of their certain advantages over organic solvents with respect to ecological, toxicological and manufacturing safety concern, high cost of organic solvents, solvent toxicity [4]. Aqueous polymeric dispersions, latexes, or pseudo latexes are all colloidal systems in which high molecular weight polymers are homogeneously dispersed in submicron sizes with the aid of surfactant(s) and other stabilizing agents. ...
... Subsequently, they are transported towards target and deposited due to the charge difference (Fig. 1). Another method is tribo-charging, which relies on frictional charging of powder that is transported through a pipe of a specific material, such as PTFE, metal or other powder particles (Fig. 2) (Bailey, 1998;Luo et al., 2008;Pawar et al., 2010). Tribo-charging produces less charge on particles than corona charging (Sumonsiri and Barringer, 2010), thus the corona charging mechanism is mostly used for electrostatic powder coating (Mazumder et al., 2006). ...
Article
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... Subsequently, they are transported towards target and deposited due to the charge difference (Fig. 1). Another method is tribo-charging, which relies on frictional charging of powder that is transported through a pipe of a specific material, such as PTFE, metal or other powder particles (Fig. 2) (Bailey, 1998;Luo et al., 2008;Pawar et al., 2010). Tribo-charging produces less charge on particles than corona charging (Sumonsiri and Barringer, 2010), thus the corona charging mechanism is mostly used for electrostatic powder coating (Mazumder et al., 2006). ...
Chapter
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