One of the Most Important Technological Inventions: Microencapsulation

You will find numerous articles and patents on encapsulation technology and its applications. It is even taught as a course in relevant university departments. Let us briefly examine the industrial applications of this important technology, which has been so extensively studied scientifically.

Encapsulation is the process of coating or containing liquid or solid particles, or a mixture, with a different material or system. Microencapsulation is a technology that enables an active material (solid, liquid or mixture) to be trapped within another type of material, forming capsules in micron or millimeter dimensions (Gharsallaoi et al., 2007). This technology first emerged in the 1930s and has continued to develop to the present day, with research accelerating particularly between 1996 and 2009. It has been developed for use in various applications across widely different sectors such as food, paints, cosmetics and pharmaceuticals. The resulting capsules are generally spherical in shape. The inner part of the sphere is called the core, internal phase or fill, while the outer covering is called the shell, shield or membrane. Core materials can be oils, vitamins and solid active substances, while shell materials can be semi-polymers, synthetic polymers or natural polymers. Among natural polymers are gum arabic, chitosan, cellulose, agar, starch and gelatin. Synthetic polymers include polyurethanes, polyamides, polystyrene and polyvinyl alcohol.

Microcapsules are materials increasingly used and further developed in pharmaceutical, textile, paints, pharmacognosy, cosmetics, food and biotechnology fields, establishing their place in today's technology sector.

Regarding the methods for obtaining microcapsules, we can examine them by dividing them into mechanical and chemical methods. Among chemical methods, in-situ polymerization and coacervation are the most frequently used. Among mechanical methods, spray drying, centrifugation and fluidized bed methods are among the most common. The capsule sizes of microcapsules depend on the mixing speed during the reaction phase and can have nano, micron or millimetric diameters. Capsules used in pharmacological and paints fields have nano-sized diameters, while capsules used in pharmacognosy, cosmetics, general cleaning or textile fields are micron-sized. Scanning electron microscopy (SEM) and optical microscopy are used in the characterization of microcapsules. Using microscopes, the size diameters and shell thicknesses of capsules can be measured, their distribution can be observed, and information about capsule quantity can be obtained. Among the uses of capsules, controlled release of the active substance in the core is the most important. This release occurs through the effects of temperature, pressure or friction. Through controlled release, the active substance is released in the desired quantity, at the desired time and location. The active duration of this system ranges from one week to one year. In the pharmaceutical field, it is used to extend drug half-lives, protect from moisture and control release at target tissues. This is because antimicrobial properties can also be added to these types of products. A prime example of vitamin microencapsulation is fish oil encapsulated with transglutaminase (TGase) enzyme, which prevents both the unpleasant smell and taste of fish oil while protecting it from oxygen, moisture and light, thereby preventing oxidation of long-chain fatty acids. Encapsulation technology was first used in the food sector in 1932, when aroma was encapsulated using gum arabic with spray drying technology. Among the primary uses in the food industry are extending shelf life and protecting active ingredients.

Encapsulated food products are primarily comprised of enzymes, aromas, vitamins, minerals and color components. Encapsulation technology is used in both human nutrition and animal feed industry.

In the paints sector, encapsulation technology is used to protect the color pigments contained in paint, to maintain the paint's color for an extended period through gradual pigment release, and to prevent damage from sunlight and moisture over time. C

apsule sizes in this area are nano-sized. With the advancement of nanoencapsulation technology in the paints industry, the most important expected benefits will be in air purification and energy storage. Nano paint coatings, through their oil and water-repellent properties, prevent dirt, fly and insect waste from adhering to surfaces. Additionally, due to the antimicrobial and antifungal properties contained in the paint, mold and bacteria do not develop on the coated surface. Reducing the time spent on cleaning and the amount of cleaning materials used is considered a major gain. Nanocapsule paints protect the coated surface from sunlight, maintaining the paint's gloss for longer, and protect from moisture, preventing rust. Surfaces coated with these types of paints are used in hotel rooms, hospital rooms, baby and children's rooms, in land transport on trucks, vans, buses, cars, motorcycles and bicycles, and in maritime transport on ships and barges. In the aerospace industry and aircraft materials, nanocapsule paints are also used on antennas and coatings. These types of paints are high-performance semi water-based and acrylic nanocapsule paints. Particularly for nanoparticle paints used in the aerospace industry, NASA itself develops testing protocols in its own R&D center. Parkim Chemicals, part of Parkim Group, supplies raw materials used in the paints industry as well as in cosmetics and general cleaning industries.

In the supply of auxiliary raw materials we assist with in general paints chemistry, we take pride in being a solution partner to our customers for issues encountered in both chemical applications and other applications, together with our R&D Center located within Parkim Fragrance House.In the cosmetics industry, dermocosmeticsor cosmetic products at the nano particle size have begun to be used for purposes such as better UV protection, deeper skin penetration, long-lasting effects and preventing stability problems.

The primary reasons for preference of nanocosmetics are that cosmetic materials at nano size have better properties such as color, solubility, permeability and spreadability compared to larger particles, enhancing consumer satisfaction. Longer shelf life is also a separate advantage. At our R&D Center within Parkim Fragrance House, through one of our TUBITAK projects involving essence encapsulation, we present current technology and knowledge to the appreciation of our customers. In conclusion, microencapsule products developed and produced through encapsulation technology in recent studies have attracted attention due to their advantages in dermatological and cosmetic applications and increased preference for use in paints, pharmaceutical and food industries. Of course, when human health and environmental safety are considered, it must not be forgotten that these types of products should be approached carefully and their efficacy and safety should be ensured. Yeşim Yıldırım R&D Project Manager Parkim       References 1. E.Alver, GÜFBED (2018) 8 (1):26-37, Removal of Anionic Dyes and Investigation of Encapsulated Dye Storage Efficiency in Chitosan Nanoparticles Prepared by Ionic-Gelation Method, DOI: 10.17714/gumusfenbil.307356 2. S.Gökmen, R.Palamutoğlu, C.Sarıçoban, Food Technologies Electronic Journal (2012) 7 (1):36-50, Encapsulation Applications in Food Industry. 3. M.Koç, M.Sakin, F.Kaymak Ertekin. Microencapsulation and its Applications in Food Technology. Pamukkale Univ. Muh Bilim Derg. 2010; 16(1): 77-86 4. E.Gökçe, Ö.Özer, New Carrier Systems Used in Dermacosmetic/Cosmeceutical Products. Publication of the Association of Cosmetics Researchers 3, Nobel Medical Publishing, Istanbul, 2016, 77-91