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Virus-Based Nanocarriers for Targeted Drug Delivery
Published in Devarajan Thangadurai, Saher Islam, Charles Oluwaseun Adetunji, Viral and Antiviral Nanomaterials, 2022
Semra Akgönüllü, Monireh Bakhshpour, Yeşeren Saylan, Adil Denizli
Natural polymers, including albumin, heparin, and chitosan, have been used for protein, oligonucleotides, and DNA, as well as drug delivery in medical applications. Many synthetic polymers, including poly-L-glutamic acid, polystyrene-maleic anhydride copolymer, polyethylene glycol, and N-(2-hydroxypropyl)-methacrylamide copolymers, have also been used in drug-delivery applications (Cho et al. 2008). The drug can be conjugated to the polymer with a covalent bond or physically entrapped in the polymer. Both synthetic polymers (Afrooz et al. 2017), as well as natural polymers, have been utilised for nanoparticle preparation.
Separation Of The Bound And Unbound Forms Of The Radioactivity
Published in Erwin Regoeczi, Iodine-Labeled Plasma Proteins, 2019
By polymerizing just the vinylbenzene monomers, that can be done by a free-radical process, a chain is obtained which we have already encountered in Figure 10, with the difference that the group attached to every second carbon is a benzene, instead of pyrrolidone. This is polystyrene. However, if DVB is present, the cross-linked structure shown in Figure 39 is obtained. This cross-linked polystyrene is the matrix of ion-exchange resins. By keeping the polymerizing solution in a droplet distribution, the product consists of nearly perfect spheres which are subsequently sorted according to size. The size is conventionally indicated by the mesh number. For ordinary chromatographic work with gravity flow, including the removal of nonprotein radioactivity from iodination mixtures, mesh 100 to 200 (150 to 80 μ diameter) is used; smaller beads (200 to 400 mesh, 80 to 40 μ) are useful for highresolution chromatography.8
Nanocarrier Technologies for Enhancing the Solubility and Dissolution Rate of Api
Published in Debarshi Kar Mahapatra, Sanjay Kumar Bharti, Medicinal Chemistry with Pharmaceutical Product Development, 2019
Ashwini Deshpande, Tulshidas S. Patil
Synthetic polymers such as polystyrene, poly (cyanoacrylates) like poly(isobutylcyanoacrylate) (PICBA), poly (isohexyl cyanoacrylates) (PIHCA), poly(n-butylcyanoacrylate) (PBCA), poly(acrylate) and poly(methacrylate) (Eudragit), poly (methyl methacrylate) (PMMA), and polyethyleneimine can be used for oral drug delivery.
In vitro assessment of inter-kingdom biofilm formation by bacteria and filamentous fungi isolated from a drinking water distribution system
Published in Biofouling, 2019
Tiago Barros Afonso, Lúcia Chaves Simões, Nelson Lima
Since DWDS are very complex systems, of difficult accessibility, biofilm studies in situ are not common (Douterelo et al. 2014, 2018). In order to study DW biofilms separately from DWDS several devices and methodologies have been developed (Gomes et al. 2014). Microtitre plates are the most frequently used in vitro model for studying biofilm formation under strict laboratory conditions, including with DW microorganisms (Gomes et al. 2014). Despite the disadvantages they have in the reproducing conditions found in DWDS (i.e. hydrodynamic forces), polystyrene microtitre plates are commonly used as the standard bioreactor system to study adhesion and biofilm formation by bacteria and fungi isolated from these systems (Simões et al. 2010, 2015; Gomes et al. 2014). They can be used as a rapid and simple method for analysing the effects of a variety of parameters on biofilm formation as equivalent biofilms can be produced simultaneously (Simões et al. 2007a, 2010, 2015). Polystyrene also has physico-chemical surface properties similar to those of other materials used in DWDS, such as polyvinylchloride and stainless steel (Simões et al. 2007b). Regions of low shear stress easily reproduced by microtitre plates are common in DWDS, particularly in reservoirs, households pipes, corners and valves. These areas are associated with zones of abundant biofilm formation due to the high accumulation of organic material (Simões and Simões 2013). For the reasons depicted, microtitre plates were selected to study biofilm formation and behaviour of inter-kingdom biofilms containing fungi and bacteria isolated from DW.
Polystyrene nanoparticles: the mechanism of their genotoxicity in human peripheral blood mononuclear cells
Published in Nanotoxicology, 2022
Kinga Malinowska, Bożena Bukowska, Ireneusz Piwoński, Marek Foksiński, Aneta Kisielewska, Ewelina Zarakowska, Daniel Gackowski, Paulina Sicińska
Nanoplastics (NPs) and microplastics (MPs) resulting from decomposition of large pieces of plastic are pollutants of global concern. Until recently, it has been considered that the diameter of plastic NPs should not exceed 100 nm, although in the latest reports the diameter of 1000 nm has been assumed as the upper limit (Gigault et al. 2018; Rakowski and Grzelak 2020; Mitrano, Wick, and Nowack 2021). MPs are plastic particles up to 5 mm in diameter (Hartmann et al. 2019). In this work, we have adopted a traditional size of particles referring to NPs, which should not exceed a diameter of above 100 nm. Among the above-mentioned particles, polypropylene (PP) and polyethylene (PE) NPs are commonly found in the environment, while polystyrene nanoparticles (PS-NPs) are determined in smaller amounts. Polystyrene is produced by polymerization of styrene monomers and it is the fifth leading thermoplastic material on the global market. This polymer is widely used in the production of food packaging, automotive industry, electronics, household appliances, and more (ChemicalSafetyFacts.org 2020). The key to understanding the potential toxicity of NPs is their physico-chemical properties, that is, size, shape, and surface charge. We used PS-NPs because they are commercially available in different size and well-characterized by their size, shape, and lack of functionalization to understand the principles of polymer chemistry. Additionally, using scanning electron microscopy (SEM), atomic force microscopy (AFM), and dynamic light scattering (DLS), we confirmed the size and shape of the tested particles. Additionally, we performed zeta potential measurements.
Scylla Sp. Shell: a potential green adsorbent for wastewater treatment
Published in Toxin Reviews, 2022
Azrul Nurfaiz Mohd Faizal, Nicky Rahmana Putra, Muhammad Abbas Ahmad Zaini
In comparison to state-of-the-art adsorbents, the performance of crab shell adsorbents, especially for dyes removal is undeniably superior. Zazycki et al. (2019) reported a 1121 mg/g capacity of methyl violet onto chitin-derived biochar, which is higher than passion fruit peel biochar (485 mg/g). Likewise, Dai et al. (2018) examined crab shell char that reveals massive capacities of 12502 and 20317 mg/g for malachite green and congo red, respectively. These magnitudes outweigh that of recyclable acylating waste expanded polystyrene (Li et al. 2021) and Mn-UiO-66@GO-NH2 composite (Eltaweil et al. 2021), respectively.