Prevention of Microbial Contamination during Manufacturing
Philip A. Geis in Cosmetic Microbiology, 2020
Quaternary ammonium compounds consist of cationic surfactants. They are most frequently used in combination with a nonionic detergent as a disinfectant-detergent or detergent-sanitizer. However, nonionic detergents usually do not clean as good as the more caustic cationic detergents. Quaternary ammonium compounds are more bactericidal against non-spore-forming Gram-positive bacteria, less active against Gram-negative bacteria and are not sporicidal, but are sporostatic (inhibitory to spore germination or outgrowth) (76,85,86) The typical use concentration for a quaternary ammonium compound sanitizer is 200 ppm. The advantages are that they can clean and deodorize at the same time, are most effective at neutral or slightly alkaline pHs, are odorless and are very stable. The disadvantages are that they are not sporicidal, their antimicrobial activity can be inactivated by anionic cleaners, use of hard water for preparing use concentrations will adversely affect the antimicrobial activity, rinsing is required to remove equipment surface residues and are less effective against pseudomonads (87,88).
Antagonists at Muscarinic Cholinergic Receptors
Kenneth J. Broadley in Autonomic Pharmacology, 2017
Urinary bladder dysfunction associated with a failure to store urine may be divided into two forms of urinary incontinence: urge incontinence and stress incontinence. Urge incontinence is an involuntary loss of urine associated with a strong desire to void. It may be subdivided into motor and sensory forms. Motor urge incontinence occurs where there is increased contractile activity of the bladder brought on by outflow obstruction, inflammation or irritation, as might occur with the infection associated with cystitis. Stress incontinence is not due to bladder hypertonicity, but more likely to sphincter dysfunction. This may arise from weakness of the skeletal muscle of the pelvic floor which is associated with the external sphincter at the neck of the bladder. It may also be caused by damage to the nerves innervating this musculature. The anticholinergic drugs are therefore not effective in this condition. They do have widespread application in urge incontinence in the elderly, in children suffering from nocturnal enuresis, to reduce urinary frequency in spastic paraplegia, and where bladder hyperactivity is associated with irritation (cystitis). The anticholinergic drugs in current use include propantheline and emepronium. Since they are quaternary ammonium compounds, bioavailability is poor, they are poorly transported to the CNS, and have only peripheral side-effects including dry mouth, blurred vision and tachycardia. Dicyclomine has also produced favourable results in urinary incontinence.
Microbial environment of the manufacturing plant
Philip A. Geis in Cosmetic Microbiology, 2006
Quaternary ammonium compounds consist of cationic surfactants. The most frequent use for this type of chemical sanitizer is in combination with a nonionic detergent as a disinfectant–detergent or detergent–sanitizer. However, nonionic detergents usually do not clean as well as more caustic cationic detergents. Typically, one can achieve more effective cleaning and sanitizing by separating the cleaning and sanitizing steps rather than combining them. This is because most cleaners operate best at high pH levels and most disinfectants operate best at acidic to neutral pH.
Efficacy of infection control interventions, other than decolonization, in reducing the incidence of new MRSA acquisition in a neurosurgical intensive care unit
Published in Infectious Diseases, 2018
Eunsung You, Sung-Shin Kim, Juyeon Lee, Tae Yang Yu, Jihyun Cho, Jae Hoon Lee
This study was a pre- and post-intervention study, and all data were collected retrospectively. The neurosurgical intensive care unit had two private rooms and six beds that had a spatial separation of 2.2 m from one another. During the pre-intervention period, the infection control procedure consisted of active surveillance, weekly review meetings, education, hand hygiene, and environmental disinfection. Active surveillance cultures were obtained at the time of neurosurgical intensive care unit admission, weekly during hospitalization, and at discharge from the unit. However, patients identified as carriers of MRSA did not need retesting. Swabs were collected from the anterior nares and the cutaneous area in the groin, and inoculated into chromID™ MRSA agar. The results were reported within 24 h. Environmental disinfection with the quaternary ammonium compounds was performed twice a day.
Longevity of hand sanitisers on fingers
Published in Clinical and Experimental Optometry, 2023
Parthasarathi Kalaiselvan, Muhammad Yasir, Ajay Kumar Vijay, Mark DP Willcox, Shyam Tummanapalli
The concentration of each antimicrobial ingredient in the hand sanitisers was not available in the literature or from the manufacturers. However, it is known that quaternary ammonium compounds can be toxic by disrupting mitochondrial function, altering oestrogen signalling and inhibiting cholesterol synthesis in mammalian cells in laboratory culture.32,33 Certain quaternary ammonium compounds can also be toxic or induce an inflammatory response from cells of the ocular surface.34 Therefore, it is likely that manufacturers need to balance antimicrobial activity with toxicity when formulating hand sanitisers containing quaternary ammonium compounds. Capric acid is a naturally occurring fatty acid and is on the Federal Drug Administration’s list of substances that are ‘generally regarded as safe’ (https://www.fda.gov/food/food-additives-petitions/food-additive-status-list#ftnD). This may mean that higher concentrations can be used to give maximum antimicrobial effect whilst maintaining low toxicity.
Synthesis, physiochemical property and antimicrobial activity of novel quaternary ammonium salts
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2018
Xianrui Xie, Wei Cong, Feng Zhao, Hongjuan Li, Wenyu Xin, Guige Hou, Chunhua Wang
As one of the leading causes of death worldwide, outbreaks of infectious diseases triggered by bacteria, viruses and fungi lead to over one-fourth of global deaths annually1,2. Thus, there is an urgent demand for exploring more efficient, broad-spectrum and long-lasting antimicrobial agents. Because of excellent antibacterial activities, quaternary ammonium salts (QAS) are widely used by the pharmaceutical industry for their recognised activity against fungi, bacteria, viruses and parasites3. For example, QASs are used as antiseptics and disinfectants of medical apparatus and instruments, and a variety of clinical application, such as preoperative disinfection of unbroken skin and trauma4–9. With more and more resistant organisms continue to emerge on clinic, the ideal antimicrobial agents should have to possess strong antibacterial activity, be safe in relation to humans and should not persist in the environment for a long time10. Some of the quaternary ammonium compounds fulfil these conditions have been invented and received increasing attentions as antibacterial agents11–13. Especially, long-chain alkyl-QAS compounds show unsurpassed antibacterial effects. It is well-known that the antibacterial activity and drug toxicity are influenced by the alkyl chain length of these agents14,15. As the growth of the alkyl chains, the antibacterial activities gradually increase, until reaching a reasonable limit. Unfortunately, drug toxicity of QAS bearing longer-chain alkyl groups also strengthen as well as benzyl-QAS. Tremendous research efforts have been devoted to development of alternative antibacterial therapeutics that are not easily forming resistance, such as quaternary ammonium salts (QAS), which destruct cell membrane of bacteria and induce the leakage of intracellular components from bacterial cells16. Thus, it becomes urgent to design and prepare one kind of novel antibacterial with higher antibacterial activities and lower drug toxicity. Many discrete QAS17 and polymerised quaternised materials (such as quaternised chitosan18,19) were reported with good antibacterial activities because of quick disinfection and sterilisation.
Related Knowledge Centers
- Ammonium
- Detergent
- Organic Chemistry
- Ph
- Polymer
- Organyl Group
- Ion
- Salt
- Polyquaternium
- Antimicrobial