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1,4-Dioxane Chemistry, Uses, and Occurrence
Published in Thomas K.G. Mohr, William H. DiGuiseppi, Janet K. Anderson, James W. Hatton, Jeremy Bishop, Barrie Selcoe, William B. Kappleman, Environmental Investigation and Remediation, 2020
Food additives have been regulated in the United States and Europe for their 1,4-dioxane content. The U.S. Food Chemicals Codex restricts residual 1,4-dioxane content in polysorbates to 10 mg/kg. Polysorbate 60 [polyoxyethylene (20) sorbitan monostearate] is an emulsifier used in ice cream, frozen custard, ice milk, fruit sherbet, and other frozen desserts. Polysorbate 60 is used alone or in combination with polysorbate 65 and/or polysorbate 80. Polysorbates have been found to contain trace levels of 1,4-dioxane and ethylene oxide as impurities, which result from the production processes used for polysorbates (FDA, 1999). Polysorbate 60 and polysorbate 80, which are produced from the polymerization of polyoxyethylene, have historically been found to contain 1,4-dioxane (Birkel et al., 1979). Levels of 1,4-dioxane in these compounds have been reported to range from 5 to 6 ppm (mg/L) (ATSDR, 2004).
Drug Solubility and Solubilization
Published in Sandeep Nema, John D. Ludwig, Parenteral Medications, 2019
Ching-Chiang Su, Lan Xiao, Michael J. Hageman
Polysorbate 80 is a nonionic surfactant commonly used in parenteral formulations. Chlordiazepoxide (Librium™) comprises 4% of polysorbate 80 along with 20% propylene glycol and is injected undiluted intramuscularly. Quite often the surfactant containing formulation is diluted prior to intravenous administration to reduce toxicity. For example, amiodarone hydrochloride has a water solubility of 0.7 mg/mL, which is solubilized to 50 mg/mL in Cordarone™ by a combination of 10% polysorbate 80 and pH adjustment to 4.1. It is administered by intravenous infusion after a 25-fold dilution with dextrose 5%. Solutol HS-15 is a newer nonionic surfactant for parenteral formulation. Solutol HS-15 is used up to 50% to solubilize propanidid, 7% to solubilize vitamin K1. Solutol HS-15 has also been used in preclinical formulations to prepare supersaturated injectable formulations of water-insoluble molecules (65).
Research Progress in Synthesization, Coating, and Characterization of Magnetic Nanoparticles
Published in Francisco Torrens, A. K. Haghi, Tanmoy Chakraborty, Chemical Nanoscience and Nanotechnology, 2019
Lavanya Tandon, Poonam Khullar
The oleic acid-coated superparamagnetic nanoparticles (NPs) were prepared by thermal decomposition of iron(III) acetylacetonate as a precursor and oleic acid as primary ligand in benzyl ether.70 These MNPs are typically coated with hydrophobic ligands. Therefore, it was necessary to modify the surface coating to make the MNPs more water-soluble and biocompatible. Polysorbate 80 is a biocompatible compound commonly used for biochemical applications and in the food production industry due to its nontoxic and biodegradable properties.71 Also, other important features of polysorbate 80 are that it is commonly used as protein stabilizer and blocking agent for nonspecific binding.72 Polysorbate compounds are composed of three functional groups: (1) the aliphatic ester chains, which prevent nonspecific binding of biomolecules, (2) hydrophilic three-terminal hydroxyl groups, which can be modified for further applications, and (3) an aliphatic chain that can easily adsorb on a hydrophobic surface of oleic-coated MNPs via noncovalent interactions (Fig. 10.S1).73,74 Prior to the modification of the oleic-coated MNP surface, the terminal hydroxyl groups of polysorbate 80 are replaced with carboxyl groups using succinic anhydride.75 The carboxyl group can be readily conjugated with amine-functionalized targeting moieties, such as antibodies. Hydrophilic PCMNCs were synthesized using a water-in-oil microemulsion technique (Figs. 10.1B and 10.S2).76 The size increments of MNP clusters are induced using polysorbate 80, which have a low Critical Micelle Concentration (CMC), and an Evaporation Induced Self Assembly (EISA) method. In the last step of the process, the carboxyl group of polysorbate 80 on O-antibody-coated polysorbate 80-coated magnetic nanoclusters (PCMNCs) is conjugated with the amine group of the antibodies.
Stable and bioactive W/O/W emulsion loaded with “Pitanga” (Eugenia uniflora L.) leaf hydroethanolic extract
Published in Journal of Dispersion Science and Technology, 2022
Larissa Tessaro, Carla Giovana Luciano, Maria Fernanda Libório Martins, Ana Paula Ramos, Milena Martelli-Tosi, Paulo José do Amaral Sobral
In a previous study, Tessaro et al.[20] developed a very stable W/O emulsion encapsulating the “Pitanga” leaf’s hydroethanolic extracts. Thus, using this emulsion to produce a W/O/W emulsion can increase the potential use of this product regarding aqueous systems as foodstuffs or biopolymers based films.[21] In this case, the stabilization of outer interface of W/O/W emulsion is enabled with the presence of a hydrophilic emulsifier which is incorporated into outer water phase before secondary emulsification.[22] Polysorbate 80 (tween 80) is a nonionic hydrophilic emulsifier that can quickly and effectively reduce the interfacial tension of the two emulsions phase[23], and it can be combined with another class of emulsifier, such as proteins.[24]
An Advanced Anti-Tarnish Process for Silver Coins and Silverware—Monomolecular Octadecanethiol Protective Film
Published in Tribology Transactions, 2021
The main chemical in the fluid was octadecanethiol. Polysorbate 40 was used as an emulsifier. Propanol was used to dissolve the octadecanethiol in low concentration. With this solution, the octadecanethiol could be applied on a silver surface, but the thickness of the film could not be easily controlled. The thickness increased with the bath time and decreased with rinsing time. Some small flat silver surfaces were tested in this solution. Although the initial results looked good, after 6-month exposure in the air, some very small black dots appeared. On scanning electron microscopy analysis it was observed that the sulfur concentration at the dot locations was high. The black dots were silver sulfate formed by the multiple layers of octadecanethiol on the surface. According to the previous experience, to form a monomolecular layer on a solid surface, an extra layer remover must be used (9). After a series of screening tests, this chemical was found. It could open the bonds between the physical absorptions such as Van der Waals force but could not open the bonds of chemical reaction products. Once it was added to the solution, after an ultrasonic bath, all of the extra physically adsorbed layers were removed and only a reacted monomolecular layer was left on the surface. Fortunately, the extra layer remover was also an emulsifier for the octadecanethiol in aqueous solution. In later Fourier transform infrared (FTIR) spectrum measurement, the formed film was proved to be a monomolecular layer.
Cloud point analysis: Influence of additives on polysorbate
Published in Journal of Dispersion Science and Technology, 2018
In the literature the names polysorbate and tween are used interchangeably. While raising the temperature of nonionic surfactants, the system becomes cloudy and phase separates out at a certain value. This temperature is known as the cloud point (CP).[1,2] In general, nonionic surfactants show optimal effectiveness when they are used near/below their CP. These nonionic surfactant solutions can be strongly influenced by any type of additives present in it.[3] Many research groups have studied the effect of additives on the CP of nonionic surfactants. Mahajan et al.[3] studied the effect of glycol oligomers and triblock polymers on the clouding behaviour of tweens. It is very essential to determine the additive effect on the CP of a nonionic surfactant.[4] Recently, we had studied the clouding behaviour of mixed block-copolymers in the presence of different salts.[2] More research on the combination of nonionic surfactant with additives is required to reveal vital information. This article reports the CP measurements of polysorbates 20 and 80 in the presence of salt additives. The polysorbates are amphipathic, nonionic surfactants composed of fatty acid esters of polyoxyethylene sorbitan, being polyoxyethylene sorbitan monolaurate for polysorbate 20 (tween-20) and polyoxyethylene sorbitan monooleate for polysorbate 80 (tween-80). The chemical structures of polysorbates 20 and 80 are shown in Figure 1 [where w + x + y + z refers to the total number of oxyethylene subunits on each surfactant molecule and may not exceed 20].