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Nanomaterials in Chemotherapy
Published in D. Sakthi Kumar, Aswathy Ravindran Girija, Bionanotechnology in Cancer, 2023
P. K. Hashim, Anjaneyulu Dirisala
In a clinical study, HL with DMPC:C12(EO)23 ratio 95:5 injected patients (n = 10) showed prolonged survival in one of the patients who was in an advanced stage of B-lymphoma. Another category of HL is consisting of polymers and phospholipids [119]. For example, a mixture of polybutadiene-b-PEG and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC) can form nano-sized HL via a special thin-film hydration technique followed by extrusion [120]. HLs also can be prepared with an encapsulated drug. A melatonin analog drug, 5-methoxycarbonylamino-N-acetyltryptamine, encapsulated in HL consisting of mucoadhesive polymers (sodium hyaluronate or carboxymethylcellulose) showed a reduction in the intraocular pressure in rabbit eyes. The therapeutic effect observed in this case was partially due to the behavior of polymer components in HL that provided long-lasting hydration and lubrication at the ocular surface [121]. A related category of HLs includes lipid-coated inorganic nanoparticles [122], cyclodextrin appended liposomes [123], and gel-in-liposomes [124].
Design of Bioresponsive Polymers
Published in Deepa H. Patel, Bioresponsive Polymers, 2020
Anita Patel, Jayvadan K. Patel, Deepa H. Patel
By means of cryo-TEM, a number of block copolymer micelles have been experiential. The Cryo-TEM image analysis has been used by Zheng and coworkers to establish the corona and core dimensions of polyethylene oxide-b-polybutadiene micelles [83]. To average the dimensions from hordes of spherical micelles created from dilute solutions of Pluronic® F127 imaging analysis techniques established by Lam and co-workers [84]. Won and coworkers used cryo-TEM imaging to study polyethylene oxide (PEO)-based block copolymers [85]. The chain of diblock copolymers explored subsists in numerous micellar morphologies counting vesicle bilayers, cylinders, as well as spheres.
Organic Chemicals
Published in William J. Rea, Kalpana D. Patel, Reversibility of Chronic Disease and Hypersensitivity, Volume 4, 2017
William J. Rea, Kalpana D. Patel
Synthetic rubber can be any of many different cross-linked elastomers, such as styrene–butadiene copolymer, acrylonitrile–butadiene copolymer, C15-1,4-polybutadiene, isobutylene–isoprene copolymer (butyl rubber), poly-2-chloro-butadiene (chloroprene rubber), ethylene/vinyl acetate copolymer, ethylene–propylene copolymer, polyester polyurethane, PVC partially cross-linked plasticizers, and silicone rubber.
Influence of drying processes on the structures, morphology and in vitro release profiles of risperidone-loaded PLGA microspheres
Published in Journal of Microencapsulation, 2019
Zhaoying Wu, Mengqing Zhao, Wei Zhang, Zhao Yang, Shuxin Xu, Qing Shang
Studies find that drying process have influence on the physical properties of final microspheres (Makadia and Siegel 2011, Lv et al. 2015, Deshmukh et al. 2016), especially, surface morphology and internal structures. Xu et al. prepare two batches of chitosan microspheres (Xu et al. 2014) by air drying and freeze drying (FD), respectively. These microspheres obtained from air drying are spherical with a diameter of 232.17 ± 41.76 μm. By contrast, the lyophilised ones are irregular spheres with the diameters of 389.37 ± 69.85 μm. Furthermore, the specific surface areas and porosity of air-dried microspheres are lower than those of lyophilised ones. Shahzamani et al. develop a novel silica-polybutadiene hybrid gels (Shahzamani et al. 2017) with supercritical drying (131 K, 20 MPa) and ambient pressure drying methods (60 °C, 24 h). SEM and N2 sorption isotherms results show that the hybrid gels obtained by supercritical drying have lower density and higher porosity than those fabricated with ambient pressure drying method. Lyons et al. study the influences of scrubbing solutions, washing time, and drying methods on the release profiles of risperidone (RIS)-loaded PLGA microspheres (Lyons et al. 2001), but no parameter control in the drying process is reported. Though, the fabrication process of microspheres are widely reported (Gaignaux et al. 2012, Marquette et al. 2014, Fu et al. 2017) in previous lectures, the influence of drying methods on microspheres’ properties is rarely studied, specifically, the pressures and temperatures of the vacuum drying (VD) process.
Janus nanoparticles: an efficient intelligent modern nanostructure for eradicating cancer
Published in Drug Metabolism Reviews, 2021
Farshid Gheisari, Mostafa Shafiee, Milad Abbasi, Ali Jangjou, Peyman Izadpanah, Ahmad Vaez, Ali Mohammad Amani
Even so, with the addition of a third component to the method, the problem gets more complex owing to the rapid increase in the number of variables or even probable methylation patterns (Kobaku 2019). As a direct cause, it is impossible to determine the consistency of such morphologies. Stadler was a leader in the development of block terpolymers and formed a ternary phase illustration for poly(styrene)-b-poly(butadiene)-b-poly(methyl methacrylate) (SBM) tri-block terpolymers. The phase schematic in SBM triblock terpolymers and perhaps other triblock terpolymers consists of a plurality of stage-segregated configurations on a nanometer range (Han et al. 2019; Baran 2020). Attention has been given to the synthesis of Janus particulates focused on block terpolymer volume framework, primarily block terpolymer compositions with symmetrical external parts (Hückstädt 2000). Morphological experiments on phase separating of ABC terpolymers – composed of three chemically distinct components – have been experimentally and theoretically performed. Only a small difference in the mass fraction (or even a difference in the interacting variables across the various blocks) has been identified to result in a major shift throughout the microphase-separated structure. An enhancement in the internal proportion of polybutadiene (PB), even when helping to keep the terminal blocks of poly(methylmethacrylate) (PMMA) and polystyrene (PS) symmetric, contributes to five distinct morphologies (Gröschel and Müller 2015). Small percentages of PB contribute to globular domains of PB at the lamellar phase of PS and PMMA, guided by PB cylinders with a greater rise in PB. For SBM block terpolymers with three identical mass fractions, the lamella phase by different thicknesses of PMMA, PB, and PS can be obtained (Martin 2017).
Carcinogenic and health risk assessment of respiratory exposure to acrylonitrile, 1,3-butadiene and styrene in the petrochemical industry using the US Environmental Protection Agency method
Published in International Journal of Occupational Safety and Ergonomics, 2022
Vahid Ahmadi-Moshiran, Ali Asghar Sajedian, Ahmad Soltanzadeh, Fatemeh Seifi, Rozhin Koobasi, Neda Nikbakht, Mohsen Sadeghi-Yarandi
This method involves mixing the mechanical copolymer of butadiene–acrylonitrile (BAN) with the styrene–acrylonitrile copolymer (SAN). The variety of modes is in mixing SAN with polybutadiene. Copolymerization of styrene and acrylonitrile is usually achieved by combination with polybutadiene. In general, each method leads to producing a polymer with many superior properties to high-impact polystyrene.