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Nanomaterials for Lungs Targeting
Published in Yasser Shahzad, Syed A.A. Rizvi, Abid Mehmood Yousaf, Talib Hussain, Drug Delivery Using Nanomaterials, 2022
Keerti Mishra, Akhlesh Kumar Jain
Synthetic lung surfactants, exosurf, and tyloxapol were utilized to see how they affected dendrimer-mediated transfection in eukaryotic cells. The results imply that Exosurf boosted the rate of dendrimer luciferase plasmid transfection in human T-cell leukemia, but tyloxapol, a nonionic surfactant, improved dendrimer-mediated gene transfer due to enhanced porosity in the cell membrane and DNA uptake (Kukowska-Latallo, et al. 1999). Lactoferrin receptors (LfRs) were found in abundance on bronchial epithelial (BEAS-2B) cells but not on alveolar epithelial (A549) cells, indicating lactoferrin's targeting selectivity as a targeting ligand for bronchial epithelial cells. Lf-conjugated polyethylenimine branching polymer has recently been employed to transport genes to the lungs (Elfinger, et al. 2007). Rifampicin (RIF) was successfully loaded in the mannosylated dendritic architecture for the discriminating distribution of RIF in alveolar macrophages. At pH 7.4, drug release, hemolytic toxicity, and cytotoxicity were significantly reduced, but drug release and alveolar macrophage uptake were significantly boosted at pH 5.0. In addition, the device was biocompatible and has demonstrated RIF delivery to particular sites (Kumar, et al. 2006). Methylprednisolone-polyamidoamine dendrimer (PAMAM G4-OH) complex was prepared for the effective treatment of asthma, which showed a significant increase in dendrimer residence times when compared to the free drug. Furthermore, after 24 hours of intranasal delivery, more than 35% of the total dendrimer was recovered from the lung (Kannan, et al. 2005).
Solid Lipid Nanoparticles (SLN) for Drug Delivery
Published in Vladimir Torchilin, Mansoor M Amiji, Handbook of Materials for Nanomedicine, 2011
Judith Kuntsche, Karsten Mäder
A wide variety of emulsifiers are used for the preparation of SLN dispersions (e.g., purified soybean and egg lecithin,30,43,54,55,66,67,70,71,82,106,108,112,165,171,180,197 hydrogenated phospholipids and synthetic phospholipids,51,55 poloxamers,44,65,67,69,71,111,130,136,137,165,201 Tyloxapol,42,43 Solutol HS 15,49,56 Brij 78,59,87,88 bile salts30,43,44,70,197 polysorbates51,52,87) pegylated lipids were sometimes added to alter the surface properties of the nanoparticles and to reduce a rapid uptake of the SLN by the RES.57–59 Often a combination of emulsifiers is advantageous. For example the stabilization of triglyceride nanoparticles with only phospholipids led to gel formation upon solidification of the nanoparticles whereas the addition of a co-surfactant as e.g. sodium glycocholate or Tyloxapol could prevent gelling.60 The gelling phenomenon was attributed to the instability of the nanoparticles upon crystallization. Nanoparticles from pure single-fatty acid triglycerides possess a strongly anisometric platelet-like particle shape. Upon crystallization and formation of the platelets an enormous increase of the surface occurs and must rapidly be stabilized by emulsifiers dissolved in the aqueous phase.
Advances in colloidal dispersions: A review
Published in Journal of Dispersion Science and Technology, 2020
Cang Huynh Mai, Tung Thanh Diep, Thuy T. T. Le, Viet Nguyen
In general, surfactants play an important role in the production of SLNs[123–125] due to their effect on the surface properties of nanoparticles. During homogenization, the particle size is reduced significantly resulting in the rapid increase of surface energy. The surfactant molecules should be redistributed on the surface of new particles to establish the new kinetic equilibrium that prevent the particles combination as well as limiting their size. Therefore, the choice of right surfactants and their appropriate doses are key steps in SLNs preparation. Many types of surfactants were investigated including phospholipids (lecithin, phosphatidylcholine), ethylene oxide/propylene oxide copolymers (poloxamer 188), sorbitan ethylene oxide/propylene oxide copolymers (polysorbate 20, polysorbate 60, polysorbate 80. Low molecular weight surfactants (Sodium dodecyl sulfate – SDS) can be rapidly distributed while high molecular weight surfactants (lecithin, poloxamer) often require a longer time. However, low molecular weight surfactants are poorly compatible with the lipid phase. Therefore, the combination of surfactant mixtures is often favored. For example, using a mixture of tyloxapol/lecithin has a lower particle size and higher storage stability than sole surfactant.[124, 126]
Anti-hyperlipidemic effects of Campomanesia xanthocarpa aqueous extract and its modulation on oxidative stress and genomic instability in Wistar rats
Published in Journal of Toxicology and Environmental Health, Part A, 2019
Joubert Aires De Sousa, Jayne Torres De Sousa, Fernanda Brião Menezes Boaretto, Jeferson De Oliveira Salvi, Jean Fachini, Juliana Bondan Da Silva, Julia Pereira Unfer, Mariangela C Allgayer, Maria Luísa Brodt Lemes, Norma Possa Marroni, Alexandre De Barros Falcão Ferraz, Jaqueline Nascimento Picada
The experimental procedure was performed according to previous studies (de Sousa et al. 2017; Rasouli, Tahmouri, and Mosavi-Mehr 2016) with minor modifications. Wistar rats were divided into six groups containing five animals each: PBS+PBS; Ator+PBS, PBS+T; 250 + T, 500 + T, Ator+T. Atorvastatin (Ator) was used as a reference for hypolipidemic agent. The CxAE doses were selected based upon a previous preclinical study in which de Sousa et al. (2019) showed that these doses did not induce toxic and genotoxic effects. Animals received either PBS, Ator 10 mg/kg, CxAE 250 or 500 mg/kg once a day for seven consecutive days by gavage (1 ml/100 g body weight). On the seventh day, rats were fasted for 12 hr received PBS or tyloxapol (T) (400 mg/kg) by intraperitoneal (i.p.) injection (1 ml/100 g body weight), according to the group, after 150 min of the last administration of PBS, Ator, or CxAE. All rats were euthanized 24 hr after the T or PBS injection. The success of the hyperlipidemia induction was verified by significantly increased cholesterol and triglyceride levels in blood samples of tyloxapol-treated animals compared to corresponding levels in samples from PBS+PBS group. A group with three animals treated with a single dose of cyclophosphamide 50 mg/kg by i.p. injection was included as a positive control for the micronucleus (MN) test.
Drying of Vaccines and Biomolecules
Published in Drying Technology, 2022
Bhaskar N. Thorat, Ayantika Sett, A. S. Mujumdar
The use of tyloxapol as surfactant and lactose as excipients in spray freeze-dried insulin, increases the stability of protein as compared to the conventional FD process. The quality of insulin was checked in terms of formation of a covalent dimer form of insulin, whose concentration was found to be minimally affected by the choice of the dryer.[58] The SEM images of freeze dried and spray dried insulin have been depicted in Figure 6.