Chitin (C8H13O5N)n ( KY-tin) is a long-chain polymer of N-acetylglucosamine, an amide derivative of glucose. Chitin is the second most abundant polysaccharide in nature (behind only cellulose); an estimated 1 billion tons of chitin are produced each year in the biosphere. It is a primary component of cell walls in fungi (especially filamentous and mushroom forming fungi), the exoskeletons of arthropods such as crustaceans and insects, the radulae, cephalopod beaks and gladii of molluscs and in some nematodes and diatoms. It is also synthesised by at least some fish and lissamphibians. Commercially, chitin is extracted from the shells of crabs, shrimps, shellfish and lobsters, which are major by-products of the seafood industry. The structure of chitin is comparable to cellulose, forming crystalline nanofibrils or whiskers. It is functionally comparable to the protein keratin. Chitin has proved useful for several medicinal, industrial and biotechnological purposes.
Ananda Mahidol was the eighth king of Siam from the Chakri dynasty, titled Rama VIII. At the time he was recognised as king by the National Assembly in March 1935, he was a nine-year-old boy living in Switzerland. He returned to Thailand in December 1945, but six months later, in June 1946, he was found shot dead in his bed. Although at first thought to have been an accident, his death was ruled a murder by medical examiners, and three royal aides were later executed following very irregular trials. The mysterious circumstances surrounding his death have been the subject of much controversy.
In organic chemistry, a carbamate is a category of organic compounds with the general formula R2NC(O)OR and structure >N−C(=O)−O−, which are formally derived from carbamic acid. The term includes organic compounds, formally obtained by replacing one or more of the hydrogen atoms by other organic functional groups; as well as salts with the carbamate anion H2NCOO−.
Chitosan is a linear polysaccharide composed of randomly distributed β-(1→4)-linked D-glucosamine and N-acetyl-D-glucosamine. It is made by treating the chitin shells of shrimp and other crustaceans with an alkaline substance, such as sodium hydroxide.
Polyelectrolytes are polymers whose repeating units bear an electrolyte group. Polycations and polyanions are polyelectrolytes. These groups dissociate in aqueous solutions (water), making the polymers charged. Polyelectrolyte properties are thus similar to both electrolytes (salts) and polymers and are sometimes called polysalts. Like salts, their solutions are electrically conductive. Like polymers, their solutions are often viscous. Charged molecular chains, commonly present in soft matter systems, play a fundamental role in determining structure, stability and the interactions of various molecular assemblies. Theoretical approaches to describe their statistical properties differ profoundly from those of their electrically neutral counterparts, while technological and industrial fields exploit their unique properties. Many biological molecules are polyelectrolytes. For instance, polypeptides, glycosaminoglycans, and DNA are polyelectrolytes. Both natural and synthetic polyelectrolytes are used in a variety of industries.
In organic chemistry, quaternary ammonium cations, also known as quats, are positively-charged polyatomic ions of the structure [NR4]+, where R is an alkyl group, an aryl group or organyl group. Unlike the ammonium ion and the primary, secondary, or tertiary ammonium cations, the quaternary ammonium cations are permanently charged, independent of the pH of their solution. Quaternary ammonium salts or quaternary ammonium compounds are salts of quaternary ammonium cations. Polyquats are a variety of engineered polymer forms which provide multiple quat molecules within a larger molecule.
Mahidol University is an autonomous public research university in Thailand. The university was founded as part of Siriraj Hospital in 1888. It was first called the University of Medical Science in 1943, and has been recognized as Thailand's fourth public university. The university was renamed in 1969 by King Bhumibol Adulyadej for his father, Prince Mahidol of Songkhla, known as the "Father of Modern Medicine and Public Health in Thailand".
Galyani Vadhana, Princess of Naradhiwas was a princess of Thailand and the elder sister of King Ananda Mahidol and King Bhumibol Adulyadej. She was also a direct granddaughter of King Chulalongkorn and Queen Sri Savarindira and also aunt of King Vajiralongkorn.
Princess Chulabhorn of Thailand, the Princess Srisavangavadhana is a princess of Thailand, the youngest daughter of King Bhumibol Adulyadej and Queen Sirikit, and the younger sister of King Vajiralongkorn. She is officially styled Her Royal Highness Princess Chulabhorn, which corresponds to her full Thai title Somdet Phrachao Nong Nang Thoe Chaofa Chulabhorn Walailak Agrarajakumari. In 2019, she was bestowed the second-highest of royal ranks by appointment – "Krom Phra" by King Vajiralongkorn. She also received a first-class King Rama X Royal Cypher Medal.
Faculty of Medicine Siriraj Hospital, Mahidol University is the oldest and largest medical school and the oldest of any kind of university faculty in Thailand. The faculty is now part of Mahidol University. Founded in 1889, the faculty was run in co-operation with Siriraj Hospital, the first public hospital in Thailand, which provides students with clinical experience. The faculty's campus and hospital is in the Bangkok Noi District, Bangkok, on the former Rear Palace. The medical school accepts about 250 students for undergraduate education and more than 100 to postgraduate studies each year.
The Thai Institute of Chemical Engineering and Applied Chemistry (TIChE) is a professional organization for chemical engineers. TIChE was established in 1996 to distinguish chemical engineers as a profession independent of chemists and mechanical engineers.
Poly(acrylic acid) (PAA; trade name Carbomer) is a polymer with the formula (CH2-CHCO2H)n. It is a derivative of acrylic acid (CH2=CHCO2H). In addition to the homopolymers, a variety of copolymers and crosslinked polymers, and partially deprotonated derivatives thereof are known and of commercial value. In a water solution at neutral pH, PAA is an anionic polymer, i.e., many of the side chains of PAA lose their protons and acquire a negative charge. Partially or wholly deprotonated PAAs are polyelectrolytes, with the ability to absorb and retain water and swell to many times their original volume. These properties – acid-base and water-attracting – are the bases of many applications.
Potato starch is starch extracted from potatoes. The cells of the root tubers of the potato plant contain leucoplasts. To extract the starch, the potatoes are crushed, and the starch grains are released from the destroyed cells. The starch is then left to settle out of solution or separated by hydrocyclones, then dried to powder.
Polymers with the ability to kill or inhibit the growth of microorganisms such as bacteria, fungi, or viruses are classified as antimicrobial agents. This class of polymers consists of natural polymers with inherent antimicrobial activity and polymers modified to exhibit antimicrobial activity. Polymers are generally nonvolatile, chemically stable, and can be chemically and physically modified to display desired characteristics and antimicrobial activity. Antimicrobial polymers are a prime candidate for use in the food industry to prevent bacterial contamination and in water sanitation to inhibit the growth of microorganisms in drinking water.
An antimicrobial surface is coated by an antimicrobial agent that inhibits the ability of microorganisms to grow on the surface of a material. Such surfaces are becoming more widely investigated for possible use in various settings including clinics, industry, and even the home. The most common and most important use of antimicrobial coatings has been in the healthcare setting for sterilization of medical devices to prevent hospital associated infections, which have accounted for almost 100,000 deaths in the United States. In addition to medical devices, linens and clothing can provide a suitable environment for many bacteria, fungi, and viruses to grow when in contact with the human body which allows for the transmission of infectious disease.
In polymer chemistry, graft polymers are segmented copolymers with a linear backbone of one composite and randomly distributed branches of another composite. The picture labeled "graft polymer" shows how grafted chains of species B are covalently bonded to polymer species A. Although the side chains are structurally distinct from the main chain, the individual grafted chains may be homopolymers or copolymers. Graft polymers have been synthesized for many decades and are especially used as impact resistant materials, thermoplastic elastomers, compatibilizers, or emulsifiers for the preparation of stable blends or alloys. One of the better-known examples of a graft polymer is a component used in high impact polystyrene, consisting of a polystyrene backbone with polybutadiene grafted chains.
Karen L. Wooley is an American polymer chemist. She is a Distinguished Professor at Texas A&M University whose research focuses on developing novel polymers and nanostructured materials.
Chuanyi Wang is a Chinese American, environmental chemistry scientist, academic, and an author. He is a Distinguished Professor and Academic Dean at the School of Environmental Science and Engineering at the Shaanxi University of Science & Technology. He is recognized for his research in environmental photocatalysis, environmental materials, surface/interface chemistry, nanomaterials, and pollution controlling.
Araneus ventricosus is a nocturnal orb-weaver spider found primarily in China, Japan, and Korea that has been involved in numerous research studies and is easily identified by its nocturnal web-building behavior. Araneus ventricosus' venom is effective against invertebrate prey, but it's venom is ineffective in vertebrates. This arachnid's silk has been researched extensively and has several unique properties. For instance, Araneus ventricosus is able to produce flagelliform silk, and full genomes have been established for its TuSp1 and AcSp1 genes. The spider also has unique eyes that are affected by their circadian rhythm and imply the existence of an efferent optic nerve within the species' central nervous system.
Mutan is a sticky colorless water-insoluble glucan with predominant α-1-3 linkages is the major component of dental biofilms, which enhances the formation of dental plaque and dental caries. It is a source made from glucans which are derived form glucose monomers. Little to nothing is known about the alpha glucans that make up the water-insoluble linkages of mutan with dexteran. These values can be derived using NMR techniques.
