Quaternary+ammonium+compounds


 * QUATERNARY AMMONIUM COMPOUNDS:**

Also known as Quaternary Ammonium //Salts,// these compounds, commonly called QUATS, are formed from Ammonium Cations combined with various anions. Chemically their basic structure is:

Where X represents the (variant) Anion.
 * ||  || R2 ||   ||   ||
 * ||  || I ||   ||   ||
 * R1 || - || N+ || - || R3, X ||
 * ||  || I ||   ||   ||
 * ||  || R4 ||   ||   ||

QUATS find application based on their strong affinity for surfaces; they are powerful surfactants. They characteristically ADsorb to surfaces and form a single layer which often acts as a barrier to other substances. This action makes QUATS ideal for use in various hair and skin care products, including shampoo, conditioner, lotions and skin disinfectants. QUATS are classified as being either 1) Bacteriostatic or 2) Bacteriocidal, depending on strength of the solution. Some QUATS have also found application as disinfectants or antibacterials, examples being Benzalkonium Chloride (brand name: ZEPHIRAN CHLORIDE), a soak for disinfecting instruments and glassware, and Cetylpyridium Chloride (brand name: CEEPRYN), active ingredient found in CEPACOL brand mouthwash. Their mechanism of action varies somewhat depending on concentration and other associated chemicals, but the dominant action is reduction of surface tension of water surrounding cells, thus causing lysis (destruction) of cell membranes of target organisms. Another application of a QUAT is Nonoxynol-9, a compound widely used as a spermicide in contraceptive foams and suppositories. While it is reportedly quite effective in killing sperm cells, a major and perhaps unanticipated side effect of N-9 is that its surfactant action temporarily strips protective layers from mucous membranes and thus may well increase risk of disease transmission during sexual activity. One additional application if in the automotive industry, where QUATS are employed to aid in drying of cars after use of QUAT-containing detergents, and in various finishes, where QUATS contribute to a water-beading effect. QUATS (and related POLYQUATS) are elso effective algaecides and thus find application in swimming pool chemicals... The selection of such compounds is often based on factors such as cost, foaming action and potential irritation of skin, respiratory tract and mucous membranes. The surfactant action of QUATS (especially Benzalkonium Chloride) carries a risk of inducing respiratory disease in those with working in high airborne concentrations or long-term exposure. Some retrospective studies have demonstrated that occupations with highest exposure to QUATS also have significantly higher incidences of occupational asthma. In funeral service applications, QUATS may be found in certain hand-sanitizer products, either as an active antibacterial agent, or as a surfactant to aid in suspension of other chemicals. In earlier times, ZEPHIRAN Chloride (Benzalkonium Chloride) was used in disinfecting instruments in the preparation room, but with the advent of other, more effective agents, (e.g., glutaraldehyde) use of this mild QUAT has passed into obsolescence.