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Tubal Patency Assessment (Focusing on Hysterosalpingo-Contrast Sonography)
Published in Arianna D'Angelo, Nazar N. Amso, Ultrasound in Assisted Reproduction and Early Pregnancy, 2020
ExEm gel and foam (GynaecologIQ, Delft, the Netherlands) were developed specifically for imaging the fallopian tubes [7]. The preparations consist of hydroxyethylcellulose, glycerol, and purified water and remain in the fallopian tubes for about 5 minutes. ExEm gel and foam have no known side effects.
Conditioning of Hair
Published in Dale H. Johnson, Hair and Hair Care, 2018
Disperse the hydroxyethylcellulose in the water. When dispersed, heat to 60°C to 90°C. Add the cetyl alcohol, quaternium-18, stearyl alcohol, stearamido-propyl dimethylamine, ceteareth-20, and gyceryl stearate, and mix for 10 min. Cool to 50°C and add the rest of the ingredients. Mill the mixture under high shear for 2 min and cool to room temperature.
Polysaccharide-Based Polymers in Cosmetics
Published in E. Desmond Goddard, James V. Gruber, Principles of Polymer Science and Technology in Cosmetics and Personal Care, 1999
E. Desmond Goddard, James V. Gruber
Hydroxyethylcellulose is employed extensively in industrial and personal care applications as an aqueous viscosifier. (The personal care applications will be discussed in greater detail in Section III.C.2.a.i.) It is possible to further derivatize HEC with various cationic reagents, for example, 25 or 26 (Fig. 25), which add quaternary charges randomly along the HEC backbone (110). These reactions are usually run in aqueous organic diluents that suspend and swell both the HEC and the cationic HEC products and 28) without dissolving either. Although manufacture of 27 is typically conducted using caustic, 28 is made by free-radical polymerization using techniques of emulsion polymerization. Here, the and resulting product are suspended as tiny beads in an organic medium during the grafting reaction. Isolation of the final cationic HEC derivatives is often achieved by centrifugation. Both of these cationic HEC derivatives can be characterized by their cat-
Ethylcellulose-stabilized fat-tissue phantom for quality assurance in clinical hyperthermia
Published in International Journal of Hyperthermia, 2023
Mattia De Lazzari, Anna Ström, Laura Farina, Nuno P. Silva, Sergio Curto, Hana Dobšíček Trefná
In this work, we propose a new fat-equivalent phantom that is based on an ethylcellulose (EC) gel comprising of glycerol and oil mixture. Despite its ability to form oleogels with high setting and melting temperatures [23–26], the use of EC for the production of solid phantoms has never been reported in the literature. EC is a hydrophobic polymer, meaning that it will be present in the oil phase, and no water is needed in order to disperse the polymer. This is an important difference compared to the gel systems described above [3–8,10–12]. So far, the only use of cellulose derivate in the form of hydroxyethyl cellulose (HEC) has been reported for high permittivity materials [27,28]. Nevertheless, the resulting phantom is viscous. In this work, we demonstrate that EC–glycerol gels have great potential to be routinely employed in QA procedures for HT devices. These fat tissue phantoms meet al.l the requirements in terms of thermal and mechanical properties. The dielectric properties are adequate in the 200–700 MHz band, and if the glycerol concentration is adjusted, even up to 1 GHz. The phantom exhibits a lower conductivity than human fat tissue at low frequencies (8–200 MHz). However, the numerical analysis demonstrates a potential application even for capacitive devices, which needs further experimental verification.
Preparation and use of nanogels as carriers of drugs
Published in Drug Delivery, 2021
Cuixia Li, Sreekanth Reddy Obireddy, Wing-Fu Lai
In fact, the self-assembly/crosslinking method is particularly suitable for the preparation of nanogels based on natural polymers (Xia et al., 2003; Rolland et al., 2005; Napier & Desimone, 2007). There are many hydroxyl groups on the molecular chains of natural polysaccharides, which can be grafted with and modified by polymers containing carboxyl groups. The copolymers generated can self-assemble through hydrogen bonding interactions, and upon further crosslinking reactions, nanogels can be obtained. Dou & Jiang (2007) grafted modified hydroxyethyl cellulose (HEC) with poly(acrylic acid) (PAA), and the generated copolymer (HEC-g-PAA) could self-assemble into nanoparticles in an aqueous medium. The molecular chains of PAA could be crosslinked with a crosslinking agent to finally generate pH-responsive nanogels.
Polymeric micelle nanocarriers for targeted epidermal delivery of the hedgehog pathway inhibitor vismodegib: formulation development and cutaneous biodistribution in human skin
Published in Expert Opinion on Drug Delivery, 2019
Somnath G. Kandekar, Mayank Singhal, Kiran B. Sonaje, Yogeshvar N. Kalia
VSD (purity, >98%) was purchased from Hangzhou Dayangchem Co. Ltd (Hangzhou, P. R. China). The diblock copolymer, mPEG-hexPLA (Mn of ~6080 g/mol and a polydispersity of 1.15), was kindly provided by Apidel SA (Geneva, Switzerland). Sodium and potassium chloride, sodium and potassium phosphate, formic acid, trifluoroacetic acid, Tween 80, and isopentane were purchased from Sigma-Aldrich (Buchs, Switzerland). Hydroxyethyl cellulose (HEC; M.W. ~ 300 000 g/mol) was purchased from Hänseler AG (Herisau, Switzerland). Acetone and methanol (HPLC grade), and acetonitrile (LC-MS grade) were purchased from Fisher Scientific (Reinach, Switzerland). PTFE membrane filters (0.22 μm) were purchased from VWR (Nyon, Switzerland). Ultrapure water (Millipore Milli-Q Gard 1 Purification Pack resistivity >18 MΩ cm; Zug, Switzerland) was used for formulation development and analysis.