Microbial environment of the manufacturing plant
Philip A. Geis in Cosmetic Microbiology, 2006
The surfactant industry also has a unique vocabulary for cleaning. We will describe these terms as well. A general purpose cleaner contains sodium hydroxide or sodium carbonate for alkalinity along with a sequestering agent. Some cleaners also include low-foaming wetting agents and silicates to inhibit corrosion. These cleaners are different from clean-in-place (CIP) cleaners that have the same formula as general purpose cleaners but contain nonfoaming wetting agents. A manual washing cleaner will exhibit lower alkalinity and contain a high-foaming agent. An acid cleaner contains an organic or mineral acid to remove hard water and mineral deposits. It may also include a heterocyclic nitrogen compound to inhibit corrosion and a wetting agent to allow penetration. Alkaline cleaners are of the general purpose type but they contain very high levels of sodium hydroxide or sodium carbonate. They are ideal for very difficult cleaning jobs.
Testing of Protective Effect against Liquid Chemicals
Robert N. Phalen, Howard I. Maibach in Protective Gloves for Occupational Use, 2023
In the standard EN 374-1, Part 1: Terminology and Performance Requirements, each combination of gloves/test chemicals should be classified according to the BT results and given a protection index.43 See Table 10.3. This kind of classification can probably facilitate the selection of protective gloves for a certain working situation, but it should be remembered that chemical permeation test data are not the only criteria to be taken into account in the selection process.44–46 The more recent changes in 2016 separated gloves into three classifications (Type A, Type B, and Type C) based on a set of required minimum BT performance levels and the number of chemicals tested from a list of 18 representative chemicals.43 As a result, glove products are labeled with a pictogram showing the classification Type A, B, or C, as well as identifiers for each of the chemicals used in testing the glove. Examples of the 18 test chemicals include methanol as a primary alcohol, formaldehyde as an aldehyde, diethylamine as an amine, nitric acid 65% as an oxidizing inorganic mineral acid, and ammonium hydroxide 25% as an organic base.
Introduction to Enzymes
John C. Matthews in Fundamentals of Receptor, Enzyme, and Transport Kinetics, 2017
Consider a molecule such as d-glucose (Figure 72). Suppose that we want to convert the 3-position of D-glucose to an acetate ester by reaction with acetic acid. Combining glucose and acetic acid alone is probably insufficient to produce a reaction. We need to provide the necessary conditions to cause the reaction to proceed, i.e., dilute mineral acid. After some time has been allowed for the reaction to proceed, we find that not only did we produce 3-acetyl-d-glucose as a product, we also produced acetyl derivatives of each of the other hydroxyl groups of the molecule as well as di-, tri-, tetra-, and penta-acetate derivatives. Clearly, the dilute mineral acid catalyst was not capable of providing specificity of products. We could have adjusted conditions to limit the number of unwanted products. However, we would still find it necessary to purify, out of the reaction mixture, the one product that we wanted.
Novel therapies for glaucoma: a patent review (2013-2019)
Published in Expert Opinion on Therapeutic Patents, 2019
Paolo Guglielmi, Simone Carradori, Cristina Campestre, Giovanna Poce
In order to enhance water solubility, the same inventors developed urea-based FAAH inhibitors for the treatment of glaucoma [53]. The inventors synthesized and fully characterized 39 compounds and their formulations to further test them by an in vitro/ex vivo protocol in male NMRI mice to assess the inhibitory activity, the aqueous solubility and the metabolic stability against human liver microsomes in presence/absence of NADPH. These new derivatives showed promising solubility profiles (>14 mg/mL) suitable for ocular instillation but were largely metabolized by CYP enzymes. The FAAH inhibitory activity is reported in Table 4 at 0.1 mg/Kg, po. The compounds displayed the ability to modulate the activity of FAAH with relatively high peripheral activity (liver > brain) after oral administration in in vivo (mice) as reported for the previous ones and their general structure. The nature and type of the organic or inorganic acid for salt formation were important for the biological activity and the improved aqueous solubility. The R substituent (amide, urea, sulfonamide, sulfamate, or sulfamide) was preferred in the meta position with respect to the para, whereas the alkyl spacer followed the order: n = 1>2. The aryl could be substituted (especially in the meta position) with OCH3>OH>Hal or changed to a benzodioxol-5-yl ring.
Development of antibacterial composite resin containing chitosan/fluoride microparticles as pit and fissure sealant to prevent caries
Published in Journal of Oral Microbiology, 2022
Chun-Cheng Lai, Chun-Pin Lin, Yin-Lin Wang
Occlusal fissures are complicated and easily attacked by bacteria, so fissure sealants with good sealing ability and lateral wall adaptation are needed [4]. Many commercial resin-based sealants are composed of dimethacrylate-based monomers, such as bisphenol A glycerolate dimethacrylate (Bis-GMA) or triethyleneglycol dimethacrylate (TEGDMA) with camphorquinone (CQ) and ethyl 4-dimethylaminobenzoate (EDMAB) as the most commonly used photo initiator. After an inorganic acid etches the occlusal surface, the monomers interact with each other and polymerization occurs, which enables the sealant to adhere firmly to the enamel surface [5]. Although these resin-based sealants have clinically acceptable retention rates, marginal leakages after the thermo-cycling process have been found in some laboratory studies [6,7].
The associations of circulating common and uncommon polyunsaturated fatty acids and modification effects on dietary quality with all-cause and disease-specific mortality in NHANES 2003–2004 and 2011–2012
Published in Annals of Medicine, 2021
Yuntao Zhang, Xiaoyu Guo, Jian Gao, Chunbo Wei, Shengnan Zhao, Zhipeng Liu, Hu Sun, Jiemei Wang, Lin Liu, Ying Li, Tianshu Han, Changhao Sun
Esterified fatty acids are hydrolysed primarily from triglycerides, phospholipids and cholesteryl esters using sequential treatment with mineral acid and base in the presence of heat. The extract is derivatized with pentafluorobenzyl bromide (PFBBr) in the presence of triethylamine to form pentafluorobenzyl esters. The reaction mixture is injected onto a capillary gas chromatograph column to resolve individual fatty acids of interest from other matrix constituents. Quantitation is accomplished by comparing the peak area of the analyte in the unknown with the peak area of a known amount in a calibrator solution. Calculations are corrected based on the peak area of the internal standard in the unknown compared with the peak area of the internal standard in the calibrator solution [29].
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