Clothing laundry detergents

Laundry detergent may also contain polyethylene glycol, a polymer that prevents dirt from redepositing on the clothes. This function used to be the job of phosphates. Another polymer used for this purpose is carboxy methyl cellulose, which is derived from natural cellulose but is very soluble in water. 

Do not use precipitation builders for laundry detergents, since they can leave behind insoluble deposits on clothes, causing damage on fabric and washing machine parts. 

In order to prove enzyme engineering feasibility, it was important to develop a model system. One of the prime considerations for any model would be the commercial potential of the model. Table I lists the major commercial enzymes and the market size in US dollars (5). The alkaline proteases (subtilisins) are clearly the major single class of enzymes in commercial use today, representing 25% of the total enzyme market of 600 million. The primary use of subtilisins is as additives in laundry detergents to aid in the removal of proteinaceous stains from cloth. 

Soaps react with the calcium and magnesium ions in hard water to produce soap curd that greatly reduces its effectiveness. The curds are actually insoluble calcium and magnesium salts. Synthetic laundry detergents have replaced soap for cleaning clothes in the last half century. Synthetic detergents are made from petroleum. They work like soap except they do not react with magnesium and calcium ions to form insoluble precipitates and salts. 

Alkaline protease is added to laundry detergents as a cleaning aid, and widely used in Western Europe. Proteins often precipitate on soiled clothes or make dirt adhere to the textile fibers. Such stains can... 

Be sure to use the least toxic (fragrance free) detergents possible, and, of course, always avoid chlorine-based bleaches. Natural laundry detergents (which often contain borax), and natural bleaches are available (more and more often right in your grocery store) from brands like Ecover and Seventh Generation, as well as the Web sites below. (While were on the subject of clothes, take whatever hand-me-downs are offered, and don t be shy about asking for more. Most people are thrilled for the chance to recycle.)... 

An example of this kind of work involves the enzyme subtilisin, frequently used as an additive in laundry detergents because it attacks the proteins that soil clothing. The problem, however, is that subtilisin is easily destroyed by bleaches with which a detergent is often used. Research showed that subtilisin is sensitive to bleach because a single amino acid in its primary structure—a methionine at position 22—is destroyed by bleach. By replacing this methionine with an amino acid that is not sensitive to attack by bleach, then, researchers were able to synthesize a new form of subtilisin that did not degrade in the presence of bleach for use in laundry detergents. 

Shorter washing times. Paper fibers are akin to the fibers found in clothing the reason laundry soaps are alkaline is because they wash out more readily from clothing fibers there is no such thing as an acid laundry detergent or soap ... 

A used 1 note placed in a pants pocket was laundered in a clothes washer with Duz laundry detergent to determine how much of the various elements were removed (Figure 5). This laundered note was analyzed, rubbed with gauze, reanalyzed, and the deposits on the gauze analyzed and reported in Figure 5. 

Run the washer through at least one additional cycle without clothing, using detergent and hot water, to clean the machine after each batch of pesticide contaminated items and before any other laundry is washed. 

Many powder laundry detergents contain boron compounds that help make clothes cleaner. 

Coloring agents and perfumes are added to laundry detergent, as well. 1 bet you didn t loiow that washing clothes was so complex. 

The major component of a laundry detergent is surfactant. Surfactants, alone and in combination with other ingredients, work to remove soils from the surface of the cloth through emulsification, roll-up, and electrostatic forces. A variety of different surfactants have been used in laundry detergents, and they can be classified as anionic, nonionic, and cationic. 

Fabric softeners are cationic surfactants that give clothes a soft feel. They may be incorporated in a laundry detergent or added to the wash separately. 

Antiredeposition agents are compounds added to laundry detergents to prevent the redeposition of soil on clothes. The most common examples are cellulose ethers or esters. 

However, when platinum (Pt) is used as a catalyst, the reaction occurs rapidly. In the body, biocatalysts called enzymes make most metabolic reactions proceed at rates necessary for proper cellular activity. Enzymes are added to laundry detergents to break down proteins (proteases), starches (amylases), or greases (lipases) that have stained clothes. Such enzymes function at the low temperatures that are used in home washing machines, and they are biodegradable as well. 

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