China
Africa
Explore chapters and articles related to this topic
Prevention of Microbial Contamination during Manufacturing
Published in Philip A. Geis, Cosmetic Microbiology, 2020
Sanitization is a process carried out to reduce the number and type of viable microbial contaminants on a physically-clean surface to acceptable or insignificant numerical levels (68). Rough surfaces, bad welds and other equipment defects are difficult to sanitize. Water quality with its pH, hardness and microbial bioburden is also an important factor in performing sanitization of facility and equipment surfaces. For example, pH of the water and water hardness may have an adverse effect on the antimicrobial activity of chemical sanitizers. If the microbial quality of the water is not controlled, it may serve as a source of microbial bioburden on facility and equipment surfaces. All cleaning agents must be thoroughly rinsed from equipment surfaces by using deionized water prior to the use of a chemical sanitizer because some cleaning agents are not compatible with some chemical sanitizers. For example, residues of an anionic cleanser may react with a chemical sanitizer containing a cationic surfactant, and the antimicrobial activity of the sanitizer is inactivated.
Cationic Surfactants and Quaternary Derivatives for Hair and Skin Care
Published in Randy Schueller, Perry Romanowski, Conditioning Agents for Hair and Skin, 2020
Matthew F. Jurczyk, David T. Floyd, Burghard H. Grüning
Cationic emulsifiers do offer certain advantages over anionic and nonionic components in the formulation of certain skin care products, Lanzet, in DeNavarre's book, states: "The pH of normal skin is 4.2-4.6. . . . Cationic emulsifiers are very compatible with the acid mantle and help to maintain it while anionic surfactant systems may promote keratin swelling and overtax or temporarily inactivate the buffering capacity of the skin, thus leading to irritation and lessened resistance to infection." Cationic and amphoteric surfactants are also compatible with quaternary germicides (57).
Conditioning of Hair
Published in Dale H. Johnson, Hair and Hair Care, 2018
Finkelstein and Laden (27) studied the kinetics of the adsorption process and found that quaternary salts formed micelles on the hair surface. A micelle is a molecular aggregate of 50 to 100 molecules that constitutes a collodial particle, which takes the shape of spheres with their hydrophilic groups facing outward and their hydrophobic groups facing inward. Micelle formation can occur only with the relatively longer-chain quaternary salts and then only when a sufficient concentration, called the critical micelle concentration, is reached. Increasing the chain length of a cationic surfactant increases the degree of hydrophobic interactions and thus increases the surface activity. Books by Rosen (28) and Rubingh and Holland (29) explain the surface chemistry of surfactants in detail.
Liquid laundry detergent capsules (PODS): a review of their composition and mechanisms of toxicity, and of the circumstances, routes, features, and management of exposure
Published in Clinical Toxicology, 2019
Rachael Day, Sally M. Bradberry, Simon H. L. Thomas, J. Allister Vale
Ophthalmic damage is due primarily to the concentration of surfactants in the capsule not the pH of the ingredients, which usually have a neutral pH. Less commonly, where the pH of the contents is as high as 9, alkalinity may be an additional factor in producing damage. Rabbit corneal epithelial cells were exposed in vitro to sodium dodecyl sulfate, an anionic surfactant, which resulted in elevation of intracellular calcium and intracellular acidification, dissipation of the mitochondrial membrane potential, a decrease in the ATP/ADP ratio and cell injury [16]. Other similar in vitro studies using rabbit corneal epithelial cells have shown that cytotoxicity increases the higher the surfactant concentration [17]. In vivo tests have demonstrated that the application of surfactants (which included 3 anionic and 1 cationic surfactant) caused cell death [18,19].
Evaluation of anionic surfactants effects on the skin barrier function based on skin permeability
Published in Pharmaceutical Development and Technology, 2019
Mana Okasaka, Koji Kubota, Emi Yamasaki, Jianzhong Yang, Sadaki Takata
Twelve anionic surfactant types were investigated. Sodium lauryl sulfate (Kao Co., Tokyo, Japan) and sodium polyoxyethylene lauryl ether sulfate (sodium laureth sulfate) (Kao) were examined as the sulfate series. Sodium laurate (NOF Co., Tokyo, Japan) was examined as the soap. Sodium lauroyl glutamate, sodium cocoyl glutamate, potassium cocoyl glutamate, and triethanolamine cocoyl glutamate (Ajinomoto Co., Ltd, Tokyo, Japan) were investigated as the glutamate surfactant series. Sodium cocoyl alaninate (Ajinomoto) was studied as the alaninate surfactant series. Sodium cocoyl sarcosinate (Nikko Chemicals Co., Ltd, Tokyo, Japan) was examined as the glycinate surfactant series. Sodium cocoyl methyltaurate (NOF), sodium taurate cocoyl methyltaurate (NOF), and sodium lauroyl methyltaurate (Nikko Chemicals) were included as the taurate surfactant series.
MUC1 aptamer-conjugated mesoporous silica nanoparticles effectively target breast cancer cells
Published in Drug Development and Industrial Pharmacy, 2018
Mohammad Yahya Hanafi-Bojd, Seyedeh Alia Moosavian Kalat, Seyed Mohammad Taghdisi, Legha Ansari, Khalil Abnous, Bizhan Malaekeh-Nikouei
Briefly, cationic surfactant (CTAB) and Pluronic® F127 were dissolved in the mixture of deionized water and NaOH 2 M, then stirred and heated to 80 °C for 30 min. Next, silica precursor (TEOS) was added slowly into the surfactant solution. Twenty minutes later, 3-MPTMS was added dropwise into the solution and heated to 80 °C for 2 h and then cooled down at room temperature to obtain thiolated MSN (MSN-SH) [22]. The surfactant was removed using dialysis method. MSN-SH nanoparticles were transferred to a dialysis tube (Spectra/Por® 10000 MWCO USA) and dialyzed for 24 h against a mixture of ethanol:water (50:50) and HCl. Then nanoparticles were dialyzed against water for 24 h. The mentioned process was repeated again [22,23].